Diagnosis: Distinguished from all living and extinct lonchopterids by the very broad, nonlanceolate wing (width 0.60x length); vein C with very long spinules, R₄₊₅ ending slightly beyond wing apex; arista situated apically on flagellomere I; setae on dorsum of head and thorax very long and fine; setation of head most similar to that of Lonchopterites (also in Lebanese amber).

Type Species: A. lebanica, new species.

Etymology: A-, from the Greek, “without,” or “devoid of,” and stem base from the only genus of Lonchopteridae, Lonchoptera (“spear winged”); in reference to the broadly rounded (versus lanceolate) wing shape.

Comments: Despite the broad wing with a rounded (vs. pointed) apex, numerous features indicate a close relationship of this genus with Lonchopteridae. These features include: long costal spinules, short R₁, loss of crossvein dm-cu, short cell cup; no anal lobe or alula; long setae on the head and thorax; two pairs of scutellar setae, with the apical pair upright and cruciate. Unfortunately, the presence of interfrontals (normally located just above the antennae) and long cheek setae cannot be confirmed since fractures obscure these portions of the head.

Diagnosis: As for the genus, by monotypy.

Description: A very small fly, body length ca. 1.9 mm; wing 0.40 mm. Head: Eyes well separated, red (color preserved), subcircular in lateral view, bare of micropubescence, no dorsoventral differentiation of facets (only female known). Frons: Without median furrow; inclinate/proclinate interfrontals, if present, not observable due to fractures. Ocellar setae long, fine, upright, parallel. Two pairs of long frontoorbital setae present, upright (barely reclinate). Pair of inner and pair of outer vertical setae present; inner verticals inclinate; outer verticals prolateroclinate; outer verticals longest setae on head; two inclinate setae lateral to outer vertical. No large postoccipital setae visible. Oral margin obscured, including presence/absence of oral/cheek setae. Antenna: Scape not observable, pedicel with single dorsal seta, conus appears to be absent (some visibility through cuticle); basal flagellomere short, length ca. 1.3x width, setose (more so ventrally); base of arista situated terminally on basal flagellomere; basal aristomere(s) either absent or very small and unobservable; apical aristomere long, slightly more than 2x length of rest of antenna; arista setulose, length of fine branches of arista 34x greatest diameter of trunk of arista. Mouthparts: (completely obscured). Thorax: Short, broad, with numerous long setae. Acrostichals well developed, in 2 rows of 6 setae each. Dorsocentrals in two paramedian rows, two long prescutellar dcs in each row. Two supraalar setae, 2 postalar setae; 2 long notopleural setae; presence/absence of proscutellum not determinable; scutellum with two pairs setae; apical pair long, crossed for about half their length. Wing: Short, broad, broadly rounded at apex; hyaline (no infuscate or darkened areas) (cannot discern microtrichia). C with row of 5–6 longer prehumeral setae; vein C with row of long, spinelike setae, C ends after apex R₂₊₃; Sc very faint, appears incomplete; very short (ends at approximately level of br-m crossvein). R₁ short, length approximately half that of wing; tip of R₄₊₅ ends approximately at wing apex. Cells br and bm small; crossvein br-m very short, very close to base of wing; M₁-M₂ forked, branches end on trailing edge of wing; cell cup absent; anal lobe highly reduced, alula apparently absent. Legs: Relatively long, with some longer setae. Abdomen: Hardly visible in unique specimen.

Specimens Examined: Holotype, Female, AMNH LAEIII-4, coll. Antoni Estephan, near Bcharré, Lebanon (Early Cretaceous). In the AMNH. Specimen is complete but obscured in many parts by numerous internal fractures in the amber, despite having been vacuum embedded in EpoTek resin.

Etymology: In reference to the country of origin.

Lonchopterites Grimaldi and Cumming, 1999: 82. Type species: L. prisca Grimaldi and Cumming, 1999 (Lebanese amber).

Diagnosis: (slightly revised, in italics): Antenna with aristal base situated terminally (L. prisca Grimaldi and Cumming) or slightly dorsally (L. burmensis, n. sp.); arista 2-articled, basal one minute, ringlike. Head with large pair of reclinate interfrontals; large pair of lateroclinate fronto-orbitals; ocellar setae large, inside (L. prisca) or outside of triangle (L. burmensis, n. sp.). Wing apex faintly pointed; vein C with large spinules; R₄₊₅ ending at tip of wing; R₂₊₃ and R₄₊₅ divergent at base of wing; M₁ and M₂ diverge near middle of wing; crossveins r-m and dm-cu lacking; anal lobe present, but small; anal vein short, incomplete. The genus is defined largely on the basis of features that are symplesiomorphic for the Lonchopteroidea.

Type Species: L. prisca Grimaldi and Cumming.

Diagnosis: Distinguished from the type species by the ocellar setae lying outside of the ocellar triangle; lack of inner vertical setae; base of arista slightly dorsal to apex of basal flagellomere (vs. on apex); face with smaller pair of setae lateral to vibrissae; vein R₁ slightly shorter (0.28x wing length, vs. 0.40x). Based on unique male specimen.

Description: Head: [(Seen largely in just dorsal view), total width ca. 280 µm. Eyes of male dichoptic, widely separated (150 µm near middle of frons); mesal margins diverging posterioad; dorsoventral facets undifferentiated; eye completely bare, fine setae lacking. Frons: Broad, without median furrow; pair of well-developed inclinate interfrontals present, bases very close to bases of antennae; distance between interfrontals approximately equal to that of ocellars. One pair of fronto-orbital setae present, slightly lateroclinate and reclinate; setal base very close to inner margin of eye. Interfrontal, fronto-orbital, and ocellar seta approximately equal in length. Ocellar setae reclinate and slightly lateroclinate, bases situated lateral to anterior ocellus, not within ocellar triangle. Inner vertical setae apparently lacking; outer vertical setae lateroclinate, length ca. 1.3x that of fronto-orbital. Postocellar setae lacking. Row of 3–4 stiff, inclinate postoccipital setae present on each side. Pair of large, projecting facial vibrissae present; vibrissae slightly larger than orbitals; slightly smaller seta lateral to vibrissa. Antenna: Porrect; scape small, cylindrical, bare; pedicel slightly conical, asymmetrical, distal rim with fine setulae (especially mesal margin), pedicel without conus (visible through cleared cuticle); basal flagellomere short, slightly asymmetrical and short, with fine setulae; base of arista situated slightly dorsal to apex of basal flagellomere; arista with two articles, basal one minute and ringlike, arista overall long and virtually bare, very faintly microsetulose, length ca. 220 µm (base of antenna 100 µm). Mouthparts: not visible; oral margin protruding slightly. Thorax: Fairly long, ca. 0.50 mm, ca. 0.30 mm at deepest portion; dorsally (scutum) bristly, flattened posteriad; subscutellum and anatergite not exposed. Acrostichals and dorsocentrals long, suberect, in rows extending entire length of scutum; acrostichals in two rows of 9–10 setae each (anterior setae thicker); row of slightly longer dorsocentrals lateral to this, posterior dorsocentrals more than 2x length of anterior ones. Pleural area obscured, sutures not visible, devoid of setae. Postpronotal lobe with 3 fine, long setae; notopleural area with 2 long, fine setae. Prescutellum absent; apex of scutellum slightly upraised; two pairs of scutellar setae, one apical pair (upright and cruciate), one subapical pair. Wing: Fairly slender, width 0.42x the length, length 0.85 mm, apex slightly pointed; overall faintly fuscous, membrane entirely covered with minute microtrichia; no pterostigma. No setae on any veins except C; large prehumeral costal seta absent. Costal vein terminating at apex of R₄₊₅, having row of ca. 25 long spinules on leading edge, no setae or spinules on lateral surface. Sc short, apically evanescent. R₁ very short, 0.28x the wing length; R₂₊₃ slightly sinuate, 0.82x length of wing; R₄₊₅ ends at pointed apex of wing, this vein distinctly thicker than others; M veins very faint, forked, length of fork 0.52x length of wing, stem of fork very faint, grading basally to nebulous; CuA₁ complete, reaching wing margin, slightly curved; cell bm not apparent, cell cup faint (M margin nebulous); vein A₁ present but incomplete. Crossvein br-m, bm-cu, and dm-cu absent; anal lobe present but small, with marginal fringe of ca. 12 fine, long setae; alula absent. Legs: Male protarsomeres lacking denticles; metatarsomeres lacking rows of palisade setae; pulvillus well developed, empodium setiform; metabasitarsomere slightly expanded in width, broader than any other tarsomeres, slightly shorter than metatarsomere 2. Apex of tibia with pair of short, stout, curved, spinelike setae on ventral margin; dorsal margin with erect, fine preapical seta. Abdomen: Abdominal muscle plaques apparently absent; spiracles not observable; six large tergites visible (including epandrium); segmentation of basal tergites not visible. Male Terminalia: Well developed, ventroflexed; cercus terminal; epandrium tucked ventrally, with comb of ca. 10 fine setae on medial margin; two rows of setae forming basketlike structure; surstylus not visible (possibly absent). Phallus short, terminal, spinelike. Female Terminalia: Unknown.

Specimens Examined: Holotype, male, AMNH Bu-SE15, from mid-Cretaceous of northern Myanmar, Kachin Province. Deposited in AMNH. In excellent condition.

Etymology: In reference to the source country.

Diagnosis: Very distinctive gracile, bristly, yellowish to grayish pollinose flies with lanceolate wings and having the following derived features: Male dichoptic; bristles on head long and thick, including long pair of reclinate interfrontals situated very close to anterior margin of frons; vibrissa large, gena with row of 4–5 large, protruding setae; arista preapically dorsal; thorax elongate and shallow, with scutum flattened posteriorly and scutellum near middle of notum, postscutellum very exposed (see Morphology section above for details); tibiae with bristles; male protarsus with ventral denticles. Pretarsus with empodium putatively absent (Klymko and Marshall, 2008) (SEMs I've made of L. bifurcata indicate the empodium may be highly reduced). Wing narrow, lanceolate, apex narrowly pointed, most veins with row of large setulae (except usually R₂₊₃); R₂₊₃–R₄₊₅ converge very close to wing tip; R₁ very short; venation dimorphic, with female having A₁+CuA₂ looped and apically meeting CuA₁; crossveins dm-cu and r-m absent. Abdomen with tergites I and II fused; spermathecae unsclerotized; surstyli absent.

Type Species: L. lutea Panzer, 1809, by subsequent designation.

Comments: Taxonomy on the approximately 70+ species in the genus has been by regional treatments (Systema dipterorum, 2013). The genus is probably native to the Palearctic, Oriental, Afrotropical, and Nearctic regions, the presence of Lonchoptera bifurcata (Fallén) in Australia and South America almost certainly representing introductions (Klymko and Marshall, 2008). The distribution of most native species is boreal, restricted to higher latitudes and higher altitudes for more southerly occurrences.

Lonchoptera bifurcata is very common in disturbed habitats throughout the world, particularly grassy, open, even landscaped areas. The species has particular significance in being one of few parthenogenetic Cyclorrhapha. Amongst over 2500 Nearctic specimens examined by Klymko and Marshall (2008), for example, all were females, suggestive of obligate parthenogenesis in North America; the seven known males are all European records, where parthenogenesis is obviously facultative though sex is very rare. The mechanism of parthenogenesis was reported by Stalker (1956) and Ochman et al. (1980) (under the junior synonymic name L. dubia Curran). Stalker identified four clones based on karyotypes and Ochman et al. (1980) identified nine in the Rochester, New York, area based on isozymes, so some of the chromosomally defined clones have surely diverged by further point mutations. It would be interesting to use DNA sequences to identify further clonal diversity and to determine whether the North American clones are monophyletic. Lonchoptera bifurcata is diploid (2n = 4), and its parthenogenesis is considered a result of chromosomal abnormalities, reflected by the fact that approximately 25% of the eggs do not develop (Stalker, 1956). Interestingly, the other species of Lonchoptera (all bisexual) that have been examined have metaphase 2n = 6. These obligately bisexual species are more restricted in distribution and habits; larvae where known are saprophagous, and some species are associated with seepages (reviewed in Klymko and Marshall, 2008).

Diagnosis: (female only). Acrostichals numerous, scattered, not in rows; prescutellum present, scutellum setulose; wing membrane entirely covered with microtrichia; M₁-M₂ fork short, asymmetrical; apices M₂, CuA₁, A₁+CuA₂ incomplete; crossvein dm-cu 2.5x its length from wing margin. Tibiae and tarsi without bifid scales. Basal flagellomere subcircular, arista dorsal.

Type Species: B. radicis, new species.

Etymology: Referring to the country of origin, and -peza (“foot”), a common suffix for genera of Platypezinae.

Comments: Like Electrosania in New Jersey amber, this is a basal, stem-group genus of Platypezidae (fig. 27), based on the numerous, scattered acrostichals; retention of a prescutellum; absence of dark, bifid scales on the legs; and metatarsi unmodified. It is placed in Platypezidae based on the C vein ending at the tip of M₁ (vs. being circumambient) and the short M₁-M₂ fork. The short, subcircular basal flagellomere is unusual, though not unique in Platypezidae. Melanderomyia and Microsania also have a short basiflagellomere (though usually reniform); the dorsal arista in Burmapeza, however, is unique within the family, a feature commonly seen in Syrphidae, Platypezidae, Phoridae, and Schizophora. Burmapeza can be clearly excluded from any of those cyclorrhaphan groups, and the antennal structure is considered here to be convergent.

Diagnosis: As for genus, by monotypy.

Description: (female only). Head: Somewhat flattened anteroposteriad, with broad frontal surface. Eyes bare, occupying all of lateral surface, well separated, no differentiation of facets. Median furrow of frons, interfrontal and fronto-orbital setae not observable (due to preservation); three pairs of small, stout ocellar setae present; row short, stout, postocular setae present near posterior margin of eye. Vibrissa, genal setae absent. Antenna: Scape not visible, apical rim of pedicel with fine setae; arista dorsal; basal flagellomere short, laterali flattened, subcircular in lateral view; three aristomeres present, basal two minute, apical aristomere length 1.5x that of basal flagellomere, with minute micropubescence. Mouthparts: Palp well developed, clavate; labellum barely visible.

Thorax: Scutum relatively flat dorsally. Acrostichals numerous, very fine, not in rows; 3 pairs prescutellar setae (lateralmost pair the dorsocentrals), graded row of dorsocentrals absent; 1 supraalar, 3–4 notopleurals present. Prescutellum present; scutellum relatively large, setulose on dorsal surface, posterior rim with 4 setae and smaller setulae. Wing: Relatively broad, short, width 0.5x the length; membrane entirely covered with dense microtrichia, even in cells. Two prehumeral costal setae present; vein C with 2 long rows of thick setulae that grade to fine setulae apicad; C terminates at apex of M₁. Pterostigma absent; slight tint between Sc and R₁. Sc long, terminates near middle of wing; R₁ long, runs very close to Sc at base. R₄₊₅ terminates at tip of wing, slightly deflexed in middle posteriad. Cells rm and bm complete; crossvein dm-cu 2.5× its length from wing margin; M₁M₂ fork asymmetrical (M₁ branch longer, complete), apex of M₂ abruptly incomplete; tips of CuA₁, CuA₂+A₁ incomplete (gradually faded). Cell cup large, CuA₂ curved. Anal lobe and alula well developed. Legs: Relatively unmodified, generalized. Femora stoutest and longest podomeres, especially metafemur; metatibia slightly curved femorad, with apical circlet of 5 stout, short setae. Legs without dark, bifid scales on tibiae or tarsi; with fine setulae only. Hind tarsomeres not expanded/flattened; tarsomere lengths 1 > 2 > 3 > 4 = 5. Pulvilli and empodium not observable.

Abdomen: Relatively long, slightly flattened dorsoventrally; tergites well developed (8 visible), with fine setae; tergite 7 with 2 pairs of slightly longer setae; sternites well developed but not very visible. Cercus slender, elongate, ventroflexed.

Specimens Examined: Holotype, female, JZC Bu178a, the better preserved of two specimens in the same piece of amber. The other specimen (178b) is partial (sex uncertain), and is designated as a paratype. The species description is taken mostly from the holotype, but features of the head were derived from the paratype because it is better preserved.

Etymology: From Latin (“of the root”), in reference to the basal phylogenetic position of the genus and type species within Platypezidae.

Diagnosis: (female only). Acrostichals in 2 even rows; 1 large pair dorsocentrals; M forked, slightly asymmetrical, M₂ very faint, almost spectral; cell dm short, dm-cu less than half the distance between M-Cu fork and wing margin; CuA₂ curved; microtrichia over entire surface of wing; legs without dark, bifid scales; metatarsus not inflated. With the exception of the spectral M₂ vein, these features are plesiomorphic for the Platypezidae.

Type Species: C. biacrosticha new species.

Etymology: Derived from Canada, the country of origin, and -peza (foot), a common suffix in the generic names of Platypezidae.

Comments: The new genus occupies a basal position in Platypezidae (fig. 27), based on the biserial (vs. uniserial) acrostichals, lack of bifid scales on the legs, metarsus not flattened and expanded, the short dm cell, and vein CuA₂ curved. It is interesting to note that the two Cretaceous genera known from Laurasia (Canada, New Jersey) are very basal stem groups, along with Burmapeza, n. gen. Otherwise, other Cretaceous genera, in amber from Lebanon and Myanmar, have a more derived position (fig. 27). It is possible that more basal taxa were sustained longer into the Cretaceous at higher paleolatitudes, or were relegated to higher latitudes, similar to what is seen today with Microsania, Melanderomyia, and Platypezina.

Diagnosis: As for genus, by monotypy.

Description: (Female only). Head: Eyes (partially collapsed in unique specimen) female dichoptic, eyes well separated (face and frons broad), bare, no facet differentiation or emargination of eye edges. Median furrow of frons (presence/absence) not observable; at least 2 pairs short, fine fronto-orbital setae present (fracture obscures observation of anterior portion of frons); no vertical setae; postocular setae very fine, short. Ocelli slightly raised; triangle with 1 pair short, stout, upright setae. Vibrissa, genal setae absent; occiput without large setae, circlet of fine setulae around cervical connection. Antenna: Scape setulose; pedicel about same length as basal flagellomere, with setulae on apical rim; arista terminal; basal flagellomere small, short and conical; 3 aristomeres, basal 2 minute (basalmost one longer), apical aristomere fine, with micropubescence. Mouthparts: Clypeus narrow; palp of moderate size, protruding beyond oral margin. Labellum well developed, with ~7 pseudotracheae on each lobe.

Thorax: Scutum rounded but not arched. Acrostichals in 2 even rows of ~20 setae; short, decumbent, stiff. One pair of large, prescutellar dorsocentrals present, row of ~15 small, evensized ones anterior to each; 2 rows of short, fine lateral scutal setae on each side. One short postalar seta; no supraalars; 3 short, fine notopleural setae (middle one longest). Prescutellum absent; scutellum side, short, with row of 4 pairs of setae (middle ones largest). Wing: Relatively short and broad, appears entirely hyaline (any infuscation on costal edge unapparent); membrane entirely covered with microtrichia (even on sc cell). One prehumeral costal seta present; C terminates at apex of M₁, C with well-developed spinules. Sc relatively short, apex near level of r-m vein, R₁ short, 0.6× length of wing; Sc and R₁ divergent, not parallel; pterostigma absent. Apex R₂₊₃ slightly upturned; R₄₊₅ ends near wing tip; R veins thicker than others; cells rm and bm complete; crossvein dm-cu near middle between fork of M+CuA₁ and wing apex (cell dm short). M₁₊₂ forked, slightly asymmetrical, M₂ very faint (almost spectral). Vein CuA₂ curved (not straight); cell cup large, longer than terminal vein; anal lobe well developed, alula not observable.

Legs: Lacking macrosetae, except for stout ventroapical spur on mesotibia. No dark, bifid scales on legs. Basitarsomeres of all legs equal to or slightly longer than combined length of distal tarsomeres; no metatarsomeres flattened or expanded. Puvilli well developed; empodium not observable, probably minute.

Abdomen: Tergites and sternites well developed, apparently without macrosetae. Female Terminalia: Four apical segments telescoping, approximately equal in length; cerci simple, with pair of dark hypoproct lobes protruding at base ventrally.

Specimens Examined: Holotype, female, RTMP 96,9.26. Deposited in the Royal Tyrell Museum of Paleontology, Drumheller, Alberta, Canada. The specimen is complete and in good condition, although flows and fractures within the amber prevent observation of some structures.

Etymology: In reference to the two rows of acrostichal setae.

Diagnosis: (male only). Eyes holoptic, dorsal facets larger; small prescutellum present; acrostichals in short uniserial row; wing with micro - trichia over entire surface; C ends at apex of R₄₊₅ (vs. M₁); crossvein dm-cu (cell dm) absent, CuP curved; M entirely spectral, branches of M₁M₂ fork virtually symmetrical; dark bifid scales lacking on legs; metatarsomeres not expanded; male terminalia lateroflexed to right. Except for the lack of crossvein dm-cu and the faint M vein, all these features appear plesiomorphic for the Platypezidae.

Type Species: L. azari, new species.

Etymology: From Lebanon, the country of origin, and -peza (foot), a common suffix for generic names in the Platypezidae.

Comments: Lebanopeza appears to be an extinct stem group to Microsania + Melanderomyia (fig. 27). It lacks at least four features that define these two extant genera (chars. 3, 16, 17, 18; table 2), but shares with them the loss of crossvein dm-cu (cell dm), a distinctly shortened Sc vein and somewhat shortened R₁, and reduction in the medial veins. In Melanderomyia M₂ is lost; in Microsania the base of M₁ is lost; in Lebanopeza the entire stem and fork of M₁-M₂ is extremely faint and unsclerotized.

The wing of Lebanopeza is similar to Mauritulus sospes Mostovski, preserved as a compression (along with portions of the body) in shale from the Early Cretaceous of Eurasia (Mostovski, 1995a). Both genera have a slender wing; membrane densely covered with microtrichia; R₁ straight, relatively short; C definitely (Lebanopeza) or apparently (Mauritulus) ending at the apex of R₄₊₅; M₁-M₂ fork nearly symmetrical; and crossvein dm-cu (cell dm) absent. Lebanopeza differs from Mauritulus by having a shorter Sc cell (0.3× wing length, vs. 0.45×), cell cup with apical stem of CuP+A₁ (in Mauritulus these veins join virtually at the wing margin), and in having no metatarsomeres expanded (in Mauritulus the basitarsomere is slightly expanded).

Diagnosis: As for genus, by monotypy.

Description: (male only). Entire body appears blackish, possibly velvety. Head: Eyes large (partially collapsed in unique specimen), bare, holoptic for ~10 facets; dorsal facets 2× or more the diameter of ventral ones. Ocellar triangle on tubercle, with minute pair of upright setae; small triangle of frons exposed just above antennae (bare of setulae, median furrow not apparent); interfrontal and fronto-orbital setae not observable; postocular setae appear to be minute; vibrissa absent. Antenna: Scape not observable; pedicel short, funnel shaped; arista terminal; basal flagellomere drop shaped ; 3 aristomeres, 2 basal ones small, ringlike, apical aristomere fine, length ~1.5× that of rest of flagellum, with micropubescence. Mouthparts: Small, entirely recessed into depressed oral cavity, cavity occupies almost all of face; palp not visible, possibly minute. Labellum short, fully opened and flat, with ~5 pseudotracheae per lobe.

Thorax: Scutum short, arched, black (probably velvety), the few setae are short, thick, stiff. Acrostichals in uniserial row of 4 minute setulae; dorsocentrals in graded row of 4–5 setae (posterior one largest), anterior dc about same size as acrostichals. No supraalar seta; 1 short, stout postalar; 3 stout notopleural setae just anterior to transverse suture, slightly longer than dorsocentrals. Prescutellum present but small; scutellum short, with single pair of short apical setae. Wing: Relatively slender, length 2.8× the width; with slight infuscation in Sc cell and between Sc and R₁; membrane entirely covered with microtrichia (including all cells); pterostigma absent. No prehumeral setae on C; vein C terminates at apex of R₄₊₅; C with row longer, stout setae interspersed among numerous setulae. Sc short, 0.3× length of wing; R₁ 0.7× wing length. Radial veins heavily sclerotized; medial veins virtually unsclerotized, faint. R₄₊₅ ends at wing tip; cells rm and bm nearly equal in size; crossvein dm (cell dm) absent. M₁-M₂ fork present, veins slightly divergent, almost symmetrical; length of fork approximately equal to that of stem. Cell cup large, significantly longer than terminal vein; CuP curved; A₂ very short, apically evanescent; anal lobe well developed; alula shallow, with long setae (not flattened). Halter bulb black, large, length equal to that of stem. Legs: Dark, relatively short, slender. Protibia equal to length of profemur; meso- and metatibia shorter thatn respective femur. Mesotibia with pair of short, stout apical spurs, one 2× length of other. Tibiae and tarsi with setulae, short stout ones at apex of some podomeres. Dark, bifid scales absent from all podomeres. Metabasitarsomeres not expanded. Pulvilli well developed; empodium not observable (probably minute, setiform).

Abdomen: Short, stout, about same length as thorax; 8 well-developed tergites visible, enfolded laterally, with scattered, fine setae; sternites not observable. Male Terminalia: Apical three tergites (7, 8, and 9 [epandrium]) lateroflexed 90° to right; epandrium capsulelike; surstylus digitiform, curved, suspended ventrally; cercus small, broad; postgonites with visible portion flanking phallus; phallus curved.

Specimens Examined: Holotype, male, Az 715A, in the Museum national d'Histoire naturelle, Paris. The fly is complete, preserved in a tiny chip of amber that is mounted in balsam on a microscope slide.

Etymology: Patronym for Dany Azar, for his work on Lebanese amber.

Diagnosis: Male holoptic, female dichoptic; female frons with well-developed orbitals and pair of interfrontals (latter sometimes present or visible in male); postoculars long, occiput setose. Face protruding (clypeus bulging) in female; basal flagellomere oval to subcircular; arista micropubescent. Acrostichals present, uniserial; dorsocentrals in two uniserial rows. Thorax short, deep; scutum in lateral view arched. Metabasitarsomere and tarsomere 2 (sometimes 3) laterally flattened, expanded; tarsomere 1 is longest of metatarsomeres; legs without dark, bifid scales. Wing with Sc, R₁ sclerotized, short, latter slightly over 0.5× length of wing. Pterostigma large, between entire R₁ and Sc and extends apically past R₁. Base of M₁ incomplete; wing with membrane entirely microtrichose. Cell cup small; crossvein dm-cu absent. Alula with flattened setae; male abdomen with longer setae, terminalia curled under abdomen.

Comments: This is a global genus of some 23 named extant species: 5 Australia + New Zealand, 4 Asia, 2 Pacific Islands (Vanuatu, Fiji), 2 Africa, 8 Palearctic, and 2 New World. The North American specimens are in serious need of revision (there are more than just two species), and I have also seen new species from Mexico, Peru, and Chile. Species are rather uniform externally (males are best separated using genitalia), and females of some species cannot be distinguished with certainty (e.g., Chandler, 2001).

The female specimen in Baltic amber described below is the first fossil of the genus, and it is remarkably similar to modern species. A detailed comparison of the females of world species is needed to determine whether there are features of this fossil that allow diagnosing it as a species. In the meantime, I am deferring formally naming it, just noting the impressive morphological stasis of Microsania from the Eocene to the present. Surprisingly, this is also the only definitive platypezid known in Baltic amber (though an undescribed opetiid is known), despite the centuries of collecting and studying Baltic amber insects in Europe. Interestingly, the amber piece resided for more than a century in an old collection of darkened, crazed Baltic amber insect inclusions at the AMNH, which was purchased from Wards Scientific Establishment in Rochester, New York, in the early 1900s. It was originally labelled as an empidid. The deteriorated surfaces were removed, better revealing the fly. The fly is partially coated with a milky exudate, typical of the preservation of insects in Baltic amber.

Summary: Complete female in Baltic amber; with typical array of Microsania characters (see generic diagnosis above). Additional details include the following: M, Cu veins with minute gap between apices and wing margin; bm cell and vein CuA2 appear incomplete (the former possibly an artifact of preservation); 2 pairs fronto-orbital setae, anterior pair inclinate, posterior pair latero-proclinate; strong pair of interfrontals present; pair of long, fine presutural setae (probably dorsocentrals) present; prescutellum appears present.

Description: Head: Eyes bare, red; dichoptic. Frons with faint median furrow on anterior half; pair of interfrontals present, well developed, proclinate; 2 pairs of fronto-orbitals, anterior pair inclinate, slightly more posterior pair latero proclinate. Pair of ocellar setae present, long, divergent, smaller pair posteriad. Lateroclinate pair of outer verticals present; inclinate pair of inner verticals, plus other setae on vertex; postoccipital setae well developed.

Clypeus (face) bulging; vibrissa, genal setae absent. Proboscis relatively broad but short. Antenna: Scape and pedicel short, ringlike; pedicel with setulae; arista terminal, basal flagellomere ovoid, with sensory/glandular pit and seta on dorsal surface; basal aristomere minute, short; apical aristomere long, not particularly fine, micropubescent.

Thorax: Short, deep in lateral view, rounded and slightly arched. Acrostichals uniserial, ~7 in row; dorsocentrals in pair of rows, ~7–8 setae each row, anteriormost pair long, fine, ~3× length of posterior des, ~ 5 scattered setae lateral to des. 1 large supraalar seta; 1 large postalar; 6 scattered notopleural setae. Anepisternum, katepisternum, anepimeron bare. Scutellum short, broad; with two pairs setae, apical pair cruciate; prescutellum present. Wing: Relatively elongate, length 2.3× width; darkened between Sc and R₁, with darkened area extending past apex of R₁; membrane entirely covered with well-developed microtrichia. Vein C with spinules, longer on portion from apex of R₁ to base; C terminates at apex of R₄₊₅, portion between terminus and apex of R₁ hardly sclerotized. Sc about half the length of R₁; R₄₊₅ terminates at apex of wing. Cell rm absent; cell bm open apically (bm-cu appears incomplete), crossvein dm-cu (cell dm) absent. M₁ basally incomplete; M₂ complete; between apices of M and Cu veins and wing margin with a minute gap. CuA₂ short, apically incomplete(?), cell cup small, possibly open; A₁ apically evanescent; anal lobe well developed, alula with long flattened setae. Legs: Coxa laterally attached to thorax; length of femur ≊ tibia on all legs; all podomeres setulose. Largest setae on legs stout, spine like; 2 on dorsal surface mesotibia (at 0.3× length of tibia, plus preapically); 1 dorsally on metatibia and metabasitarsomere, both preapical. Setae and setulae on all tibiae and tarsi in longitudinal rows. Mesotibia and tarsus with 2 ventral, seamlike rows of stout, short setulae. Metatarsomeres 1 and 2 with transverse rows setulae. Claws and pulvilli well developed. Metabasitarsomere barely expanded in lateral view. Abdomen: Abdomen relatively short, stout, distinctly shorter than wings; 8 well-developed tergites, 6 well-developed sternites visible. Tergites with short, scattered setae (no macrosetae), sparser on sternites; sternites nearly equal in size to tergites on same segment. Pleural membrane wrinkled and exposed between lateral margins of abdominal sclerites. Cerci small, 1-segmented, suboval.

Specimen Examined: Female, AMNH Ba-502-14, in Eocene Baltic amber. Specimen is complete and well preserved (the eyes have even retained a reddish color), but portions of the cuticle are obscured by a milky coating.

Comments: I chose not to name this fossil because I could find no diagnostic characters to separate it from extant species, one reason being it is a female.

Diagnosis: (female only). Macrosetae absent from head, thorax, and abdomen (some fine setae/setulae on legs); fine, minute acrostichals present in 2–3 irregular, short rows. Scutum strongly arched; palp large, long. Vein M₁ arched strongly away from M₂; membrane of wing mostly with microtrichia, except in basal cells; A₁+CuA₂ apically incomplete, A₂ spectral. Tibiae and tarsi with dark bifid scales; metatarsomeres 1–4 slightly flattened and expanded.

Type Species: C. divergens, new species.

Etymology: From calvus (L., “naked, bare”), in reference to the virtual lack of setae on the head and body, and -peza, a common suffix in genera of Platypezidae. The genus name is feminine.

Diagnosis: As for genus, by monotypy.

Description: (female only). Head: Broader than long, but slightly narrower than thorax. Eyes: Bare, as preserved silvery, no emargination, large (occupying nearly entire lateral surface of head); no differentiation of facets. Frons without median furrow; with few, scattered fine setulae; no interfrontal, fronto-orbital, vertical, or ocellar setae; frons margins slighly divergent dorsad. Ocelli on low tubercle. Postocular setae reduced to a few fine setulae. Oral margin slightly concave; face flat, vibrissa and genal setae absent. Antenna: Scape small; pedicel ringlike, with distal rim of fine setulae, apex short, conical; arista apical; basal flagellomere ovoid; two minute basal aristomeres present, basalmost one smaller; apical aristomere bare, hardly longer than rest of antenna. Mouthparts: Clypeus short, much broader than long; palp large, oblong, flat, light, without setae (with just setulae and microtrichia); labellum well developed, laterally flattened when closed, with fine setulae on ventral surface.

Thorax: Scutum strongly arched, neck positioned low (slightly below level of scutellum); transverse suture short, restricted to vertical-lateral portion of scutum. Acrostichals extremely fine, short, in 2–3 irregular short rows; no thoracic macrosetae (e.g., dorsocentrals, supraalars, postalars, notopleurals, scutellars). Anepisternum relatively large, katepisternum small; prescutellum absent; thorax deep in lateral view; scutellum relatively small, roughly triangular in dorsal view.

Wing: Entirely clear (no tinting, even between Sc and R₁); pterostigma absent; membrane with fine microtrichia except in cells cup, br and base of bm. Vein C with fine setulae only, lacking thick spinules; C terminates at apex of M₁; Sc and R₁ long, closely adjacent. R veins without setulae or spinules, more sclerotized than other veins. Cell rm narrow, long, bm shorter than cup; crossvein br-m very short; dm-cu distant from wing margin by 3.5× its length (cell dm short); cup large, CuA₂ slightly arched, A₂ spectral. Anal lobe well developed, alula small. Legs: Very slender; coxae relatively short; metafemur slightly longer than pro- and mesofemur; bare except for dark bifid scales on tarsi and portions of tibiae, long row of extremely fine setae on dorsum of profemur (lengths about equal to femur width). Dark, bifid scales: row on lateral edge of pro- and mesotibia, plus encircling apex of tibia; 2–3 irregular rows on metatibia; on ventral surface of pro- and mesotarsomeres 1–4. Metatarsus slightly inflated and flattened laterally, tarsomere 2 shortest, tarsomere 3 longest, with 2 ventral rows of bifid setae.

Abdomen: Relatively short, stout; eight tergites visible, 2–4 largest ones; pleural membrane extensive (tergites and sternites not meeting laterally); tergites completely bare of setae or setulae; sternites small, subcircular to almost square, each extensively isolated by membrane, 7 visible. Female Terminalia: Cercus 1-segmented, digitiform, setulose, hypoproct well developed (~ 0.5× length of cercus).

Specimens Examined: Holotype, female, AMNH BuSE-8. Paratypes JZC Bu212 (female), AMNH Bu-1510. All in Burmese amber. All are completely intact, though the holotype is particularly well preserved.

Etymology: The species name refers to the widely divergent M veins.

Diagnosis: (male only). Eyes extensively holoptic; gena bare, occiput with very fine, scattered short setae; clypeus a broad triangle; palp minute; arista bare; acrostichals entirely absent, only 1 pair of (short, prescutellar) dorsocentrals; 1 short pair of scutellars; 4–5 notopleurals. Wing entirely covered with dense microtrichia; M not forked (M₂ lost), dm-cu close to wing margin; CuP slightly curved. Tibiae and tarsi with bifid scales. Metatarsomeres 1–4 flattened, expanded; tarsomere 2 shortest, with blunt spine; tarsomere 3 with clavate seta. Abdomen short, broad; male tergite 7 narrow, tubular.

Type Species: C. anomala, n. sp.

Etymology: For Peter J. Chandler, in recognition of his work on global Platypezidae, and on Diptera in general. The genus name is feminine.

Comments: This genus is extremely similar phenetically, and apparently close phylogenetically, to Lindneromyia neomedialis, n. sp., in Dominican amber, described below. This is based on the squared oral margin, minute palps; face, gena, arista bare; complete lack of acrostichals, one (short, prescutellar) pair of dorsocentral setae; one short pair of scutellars; no supraalars, one short postalar; loss of vein M₂; r-m crossvein near level of cell Sc apex; and thick, stiff, spinelike setae on posterior margin of tergite 6 lacking. Chandleromyia differs from L. neomedialis based on the setose occiput (completely bare in Lindneromyia); 4–5 notopleurals (vs. 2); wing membrane entirely with dense microtrichia (vs. partially covered with minute, faint ones); cell dm long, with dm-cu close to wing margin (vs. cell short, vein near middle of wing); vein M₁ deflexed (vs. almost straight); vein CuP curved (vs. straight); spine and clavate seta on metarsomeres 2 and 3, respectively (vs. without); male tergite 7 narrow, tubular (vs. short, much broader than long, inserted into emargination of tergite 6).

Though separated by approximately 80 million years, the two flies appear closely related. There is no question about the provenance of the two specimens; AMNH DR14-35 was acquired in the 1990s in the Dominican Republic by me; AMNH Bu-KL30-27 was acquired from Myanmar. With a derived platypezine in the mid-Cretaceous, this greatly extends the age of crown-group Platypezidae (fig. 27).

Diagnosis: As for genus, by monotypy.

Description: (male only). Head: Large, broader than thorax. Eyes bare, large, holoptic for ∼30 facets (virtually entire length of frons except short segment above antennae). Dorsal facets (∼ 70% of eye) large, 2x diameter of ventral facets. Frontal margins of eyes emarginate around bases of antennae, margins slightly divergent ventral to this. Median furrow of frons, interfrontal, fronto-orbital setae (presence/ absence) not observable. Face entirely bare. Ocelli on tubercle, with pair of short posterior setae (length shorter than diameter of ocellus). Vertical setae absent; postoculars minute, except for short row of 4–5 short, thick seate on dorsal portion. Occiput with fine, short, scattered, light setae (lengths ca. equal to diameter of large eye facets); occipital setae do not extend to gena. Vibrissa, genal setae absent. Antenna: Scape small, barely exposed, apparently bare; pedicel small, conical, with apical circlet of setulae; arista terminal; basal flagellomere small, tapered, with incised portion mesally; two small basal aristomeres (lengths ∼3x the diameter); apical aristomere long, fine, bare of any micropubescence. Mouthparts: Oral margin squared; clypeus a broad triangle; labrum broad, apex pointed and sclerotized; labellar lobes deeply separated anteriorly, ∼0.65x lobe length; palp very small.

Thorax: Scutum convexed but not arched, flatter anteriorly. Acrostichals completely absent, even minute ones. Only 1 pair of dorsocentrals present, short, prescutellar, no smaller, graded dorsocentrals present. Supraalar setae absent; 4–5 stout notopleural setae present (4 on one side of specimen, 5 on other side); anepisternum and katepisternum bare. One pair of short, stiff postalar setae present. Prescutellum absent. Scutellum with one pair of apical setae only; setae short, stout. Wing: Length/width 2.4; hyaline, except for faint tint between Sc and R₁ Membrane microtrichia well developed over entire surface of wing, even in cell Sc. Two prehumeral costal setae at base of C; C with spinules, end near apex of R₂₊₃. Sc relatively short, apex slightly beyond level of crossvein r-m; R₁ straight, bare, length 0.72x the wing length; bases of Sc and R₁ close, divergent for apical half. Pterostigma absent. Vein R₄₊₅ ends at wing tip; cells rm and dm closed; crossvein br-m slightly basal to level of Sc apex; crossvein dm-cu close to wing margin, separated from margin 0.75x its length. M not forked (M₂ lost); M₁ bent in middle, deflected anteriad. Tip of CuA₁ incomplete; cell cup longer than vein at apex, cell not extremely acute or narrow; CuP slightly curved, not straight; CuP+A₁ tip incomplete. Legs: All femora without macrosetae, spines or tubercles. Dark bifid scales on all tibiae and tarsi: scattered on partial, lateral surface of tibiae, encircling ventral portion of tibial apex; in dense lateral row on tarsi. Metatarsomeres 1–4 flattened laterally, expanded; tarsomere 2 with blunt spine on lateroapical corner; tarsomere 3 with small, light, clavate seta preapically near row of bifid scales. Mesotibia with 2 ventroapical spurs, large one mesally (its length ca. diameter of tibia). Pulvilli well developed; empodium not observable (probably minute, setiform).

Abdomen: Tergites without macrosetae or setulae; 8 tergites visible; anterior 6 broad (1–4 broadest); tergite 7 narrow, longer than wide, tubular, ventroflexed (presumably circumverted); epandrium small, capsular. Male genitalia not observable (preservation insufficient). Sternites well developed, but lateral margins do not meet tergites (pleural membrane exposed).

Specimens Examined: Holotype, male, AMNH Bu-KL30-27, in Burmese amber. The fly is extremely well preserved, complete, though some details are obscured (e.g., small structures of the genitalia).

Etymology: In reference to the anomalously early appearance of a platypezine in the mid-Cretaceous.

Lindneromyia Kessel, 1965a: 1. Type species L. africana Kessel.

Symmetricella Kessel, 1965b: 235. Synonymy by Chandler (1989).

Plesioclythia Kessel and Maggioncalda, 1968: 58. Synonymy by Chandler (1989)

Penesymmetria Kessel and Maggioncalda, 1968: 63. Synonymy by Chandler (1989).

Diagnosis: Predominantly black, velvety; ocellars and postorbital setae short; female without fronto-orbital setae; occipital setae present, not extending to gena. Dorsocentral setae short, uniserial (prescutellar pair largest); 3–5 strong notopleurals; 1 strong postalar; 2–3 pairs scutellars. Male femora without large setae; mesotibia with 2 apical spurs; metatarsomeres 1 to 3 or 4 laterally flattened and expanded, length of tarsomere 3 ≥ 1, metabasitarsomere short. Wing with minute, extremely faint microtrichia, absent from most/all costal cells; costal edge generally slightly convex proximal to tip of Sc; M usually forked (simple [M₂ lost] in 3 extant species), fork short. Crossvein dm-cu less than twice its length from wing margin, usually much less; length of cell cup equal to or generally less than length of apical vein.

Diagnosis: (male only). Vein M unforked (M₂ lost), R₄₊₅ and M₁ slightly sinuous; gena completely and occiput virtually bare; metatarsomeres 1–4 flattened, expanded, basitarsomeres short, tarsomere 3 longest; acrostichals completely absent; only 1 (short) pair dorsocentrals and scutellars present; 2 notopleurals; wing membrane with very faint, minute microtrichia over about half of wing (mostly posteriorly); male abdominal segments 7–8 inserted into deep emargination of posterior portion of tergite 6.

Description: (male only). Head: Large, broader than thorax. Eyes bare, large, occupying all of lateral portion and much of frontal surface of head; holoptic in male from just above antennae to anterior ocellus (∼15 facets); dorsal facets about 2x diameter of ventral ones. Median furrow of frons, interfrontal setae, orbitals, verticals (presence/absence) not observable. Ocelli on tubercle; setae absent, 6 minute setulae present. Postocular setae minute, in short row along posterodorsal margin of eye; occiput otherwise bare. Vibrissa, genal setae absent. Antenna: Slight oval depression on face beneath each antenna. Scape small, bare; pedicel cup shaped, with 4–5 setulae on rim; arista terminal; basal flagellomere short, roughly drop shaped but without slender apical extension. Arista with two minute, ringlike articles at base; basal aristomere long, fine, bare (not micropubescent). Mouthparts: Oral margin and clypeus squared; clypeus thin. Palp small, with apex truncate (possibly with a pore). Labellum (opened) broad, with ∼10 pseudotracheae; labrum not observable.

Thorax: Scutum rounded but not arched; curvature greater on anterior portion; scutum and scutellum appear black, perhaps velvety. Acrostichals absent; only one pair of (short, prescutellar, inclinate) dorsocentrals present (smaller graded dcs completely absent). Supraalar setae absent; 1 short postalar; 2 short notopleurals; anepisternum and katepisternum bare. Prescutellum absent. Scutellum with only one pair of small preapical setae, divergent. Wing: Length/width 2.0, hyaline except for faint tint between Sc and R₁. Membrane with faint, minute, barely detectable microtrichia over about half the (posterior portion of) wing, including much of cell Sc. No veins with setulae or spinules; prehumeral costal seta very small; vein C with spinules to slightly past apex of R₂₊₃; C terminates at apex of M₁. Sc relatively short, close to R₁; pterostigma absent. R₂₊₃ almost straight, R₄₊₅ and M₁ slightly sinuous, convergent at wing tip; R₄₊₅ ends near wing tip; cells br, bm closed. Crossvein dm-cu short, distant from wing margin, 5x its length from wing margin (vs. ca. 0.5–3x). M unforked (M₂ lost), without abrupt bend in M₁. CuA₁ relatively straight; cell cup pointed, CuP straight (not curved); anal lobe and alula well developed. Halter knob large, dark, bulbous, length ∼ equal to that of stem. Legs: Relatively short; all femora without macrosetae, spines or tubercles. Tarsomeres 1–4 flattened, expanded; tarsomere 3 longest, 1 is broadest. All tarsomeres with posteroventral, seamlike row of dark, bifid scales; more such scales scattered over dorsum of metatarsomeres; 2 sparse rows of scales dorsally on meso- and metatibia. Mesotibia with single, short ventroapical spur, length less than diameter of tibial apex. Pulvilli well developed; empodium setiform.

Abdomen: Dark; relatively short, as preserved only slightly longer than thorax. Tergites well developed, wrap laterally, contact lateral margins of sternites (which are also well developed). Abdomen laterally with fine, erect setae; dorsally with few or no setae (probably velvety black); terminal tergites without large, spinelike setae. Six tergites visible dorsally, 2 small ones ventrally (tergites 7 and 8) (plus epandrium), all three ventroflexed (presumably completely circumverted), recessed in deep emargination on posterior portion of tergite 6. Cerci light, appear fused at bases. Posterior margin tergite 6 without thick, stiff setae; epandrium crescentic.

Specimens Examined: Holotype, male, AMNH DR14-35, from mines near Santiago, Dominican Republic (Miocene). Specimen is complete and has excellent preservation, although the surface of the amber is crazed.

Etymology: Neo-, referring to New World; and -medialis, referring to the medial vein, as this is the only New World species of the genus thus far with a simple medial vein.

Comments: Lindneromyia is the largest genus of the family, and the predominant one in the tropics. Three species in the genus have a simple medial vein: L. africana Kessel (from Kenya, type species of the genus), L. fonsecai Chandler (from Australia), and L. kesseli Bowden (from South Africa). Lindneromyia neomedialis significantly differs from these three species based on the single pair of dorsocentrals (vs. in two rows) and scutellars (vs. 2–3 pairs); lack of stiff setae on tergite 6 (which is widespread in Platypezidae); and the very distinctive, short dm-cu crossvein distant from the wing margin (vs. very close to the margin). Lindneromyia fonsecai has a very abrupt bend in M₁ (some individuals retain a spur of M₂). Lindneromyia africana is reported to lack the small basal aristomeres (which would be very unusual, perhaps an observational error), and the basal flagellomere is setose (not just with microtrichia); dm-cu is extremely close to the wing margin (∼ 0.3x crossvein length), and R₁ is quite long (terminating at level of CuA₁ apex). Despite these differences I am hesitant to accord a separate generic status to the fossil, especially since the external male terminalia agree so closely with Lindneromyia (e.g., Chandler, 1994; Chandler, 2001). Also, many of the distinctive features of L. neomedialis are autapomorphic losses.

Lindneromyia neomedialis differs from Metaclythia (monotypic: currani Kessel, known from Ontario, Canada, and Wisconsin, United States), which also has a simple M vein, based on the following: Cell dm short (vs. long), gena bare (vs. setose); single pair of dorsocentrals (vs. in graded row); scutellars in single pair (vs. two); 2 (vs. 4) notopleurals; tergite 6 lacking spinelike setae (vs. with 2 pairs).

Diagnosis: (male only). Distinguished from the other species in Dominican amber, L. neomedialis, by 2 uniserial rows of dcs (vs. only 1 pair [prescutellar] dcs); 2 pairs of scutellars (vs. 1 pair); tergite 6 with 3 pairs of stiff, spinelike setae on posterior margin (vs. none); metatarsomeres 1, 2 with seta adjacent to lateral seam of bifid scales (vs. no setae); M forked; crossvein dm-cu ∼1.3x its length from wing margin (vs. >3).

Description: (male only). Head: Width greater than thorax. Eye very large, holoptic for ∼15 facets, bare, dorsal facets 2x diameter of ventral ones; frontal margins emarginate around bases of antennae. (Silvery layer of air covers most surfaces of eyes, portions near some margins not being covered, giving appearance of emarginations on posterior and dorsal margins, but entirely an artifact). Frons mostly not observable; small triangle exposed above antennae. Ocelli on low tubercle, setae not observable. Occiput with well-developed setae; gena and postgena bare. Antenna: Entirely black like face, possibly velvety; basal 3 segments small, basal flagellomere roughly ovoid, with narrow tip (no slender extension); 3 aristomeres, basal 3 minute, apical aristomere long, thin, completely bare. Mouthparts short, almost entirely recessed into oral cavity (details not observable).

Thorax: Scutum rounded but not arched; scutum and scutellum appear black (possibly velvety). Acrostichals absent. Dorsocentrals in 2 uniserial rows ∼10 dcs each; prescutellar longest dc, twice length of adjacent dc; remaining dcs very small. No supraalar setae, 3 notopleurals; 1 postalar. Scutellum with 2 pairs marginal setae; apical pair twice the length of anterior pair; both pairs upright. Wing: Fairly short and broad, length/width 0.50. Membrane mostly bare, portions of posterior and apical margins with very fine, faint microtrichia; costal cells entirely bare. Prehumeral C seta very near wing base. Vein C ends at apex of M₁; with fine spinules, ending at apex R₂₊₃. Sc, R₁ close and parallel in basal half, membrane between them tinted; pterostigma absent; Sc ∼0.45x wing length, R₁ 0.70x wing length. R₂₊₃ terminates just before wing tip; R₄₊₅ at wing tip. M branched, asymmetrical, M₁ twice the length of M₂. Crossvein br-m at level of 0.65x Sc length; dm-cu 1.3x its length from wing margin, cell dm long. Vein CuP very slightly curved; A₁ not observable; cell cup relatively short, slightly longer than apical vein. Anal lobe well developed; alula not observable. Legs: Femora without macrosetae, spines, or tubercles. Tibiae: Long ventral row/seam bifid scales present, shorter dorsal row; presence/absence mesotibial spurs not observable; apex of mesotibia and much of metatarsomeres with thick, dark setae (lengths almost equal to tarsal width). Tarsi: proand mesotarus with biserial ventral rows of bifid scales (mesal row thickest); metatarsomeres 1–4 laterally flattened, expanded, widths 1 > 2> 3 > 4 > 5; lengths 3 > 1 > 2 > = 4 > 5.

Abdomen: Slightly longer than thorax, wings extended well beyond apex of abdomen. Six large tergites dorsally, 3 small tergites tucked ventrally (tergites 7 and 8 very short); epandrium (tergite 9) about same length as tergite 6. Tergites 1 and 2 with numerous long, fine setae laterally; middle portions of tergites 1 and 2 and others with very sparse, short setulae. Tergite 6 with 3–4 stiff, long, thick setae on posterior margin. Sternites: Only 3 large ones visible. Male terminalia: Epandrium with a few, very small scattered setulae, U-shaped in posterior view; surstylus well developed, triangular, articulates with (but not connected to) epandrium. Cerci ovoid, setulose. Other details not visible.

Specimen Examined: Holotype, Male, AMNH DR-14-736, in amber from the Dominican Republic (Early Miocene). The fly is entirely preserved, but a layer of bubbles in the amber on the right side is very close to the specimen; left lateral and dorsal views are best observed. Portions of eyes have a silvery layer of air. The fly may have been velvety black, as it reflects very little light. The amber piece was embedded in synthetic resin and trimmed close to the fly for optimal observation.

Etymology: Referring to the Dominican Republic, the country of origin.

Summary: Partial male specimen in Lebanese amber, missing most of head, some of thorax, all of legs and abdomen; wing entirely preserved. Eye with dorsoventral differentiation of facets; thorax with at least 2 pairs prescutellar dorsocentrals (presence/absence acrostichals and serial dorsocentrals not observable); wing with Sc very long, R₄₊₅ terminating at apex of wing; M forked, slightly asymmetrical; dm-cu distant from wing margin by 4x its length; cell cup short, acute, length slightly less than length of apical vein. Microtrichia not observable.

Description: (male only). Head: Eye with facets dorsoventrally differentiated (dorsal ones larger); dorsal margins lost, not observable. Occiput apparently bare. Antenna: Scape bare and pedicel lost, flagellum detached but close to body; basal flagellomere roughly triangular, with deep medial emargination; arista terminal, basal two aristomeres (flagellomeres 2 and 3) small, tubular; apical aristomere fine, longer, entirely bare. Thorax: much of it lost at surface and in amber. Acrostichals not observable; 2 pairs prescutellar dorsocentrals present, presence/absence of serial dorsocentrals not observable. Supraalar, postalar, notopleural setae not observable; 1 (pair?) scutellar setae preserved; prescutellum absent. Wing: Relatively short, broad, length/ width 1.9. Tinting between Sc and R₁ not observable; pterostigma absent. Termination of vein C not observable (wing tip and posterior edge lost at surface of amber), C with spinules. Vein Sc long, 0.55x length of wing; R₁ close and parallel to Sc, diverging at apex; R₄₊₅ ending at wing tip. Crossvein r-m short, at level of middle of Sc. M forked, slightly asymmetrical, length M₁ slightly greater than stem of M (from dm-cu). Cells rm and bm complete. Crossvein dm-cu relatively short, distant from apparent margin of wing by ∼4x its length. Cell cup slender, acute, slightly shorter than apical vein; CuA₂ straight, not curved; anal lobe large (folded in specimen), alula well developed.

Specimens Examined: AMNH JG79/76, in Acra Collection of Lebanese amber (Early Cretaceous) at the American Museum of Natural History.

Comments: The specimen is one of only two Platypezidae known from Early Cretaceous amber of Lebanon, making these among the oldest Platypezidae. The specimen is not formally named here because the only significant diagnostic characters involve the wing venation. Most of the head, much of the thorax, all legs and the entire abdomen are lost. Absence of data on acrostichals, dorsocentrals, and leg characters (e.g., bifid scales, metatarsomeres) results in too much uncertainty regarding placement. Distinctive features of the wing venation are the very long Sc vein and dm-cu distant from the apparent margin of the wing.

Ironomyia White, 1916: 216. Type species I. nigromaculata White, 1916; J.F. McAlpine, 1967 (as family); D.K. McAlpine, 2008 (revision of Ironomyia species).

Diagnosis: (based on McAlpine and Martin, 1966; J.F. McAlpine, 1967; D.K. McAlpine, 2008, with modifications): Relatively stout flies with dark, bold velvety markings that contrast with pruinescent silvery and gray areas; patterns sexually dimorphic. Head: Antennal pedicel with fingerlike lobe inserted into deep, notchlike emargination of flagellomere 1 (flagellomere 1 strongly reniform, with two “sacculi” [McAlpine, 2008], i.e., sensory pits). Proboscis relatively long and slender, labellum small. Thorax: Dorsocentral setae small, reduced in number; acrostichals in two rows. Wing: R₂₊₃ and R₄₊₅ close, parallel, slightly sinuous; cell d apically acute, with strongly oblique dm-cu; cell cup relatively short; anal lobe well developed. Abdomen and Terminalia: Tergites 1 and 2 partially fused (separated via sulcus only, no intersegmental membrane [D.K. McAlpine, 2008]); sternites well developed. Male terminalia circumverted 360°, symmetrical, ventroflexed; surstyli well developed, not fused to epandrium; postgonites absent (as in Phoridae), sternite 8 fused to epandrium, phallapodeme articulated (Sinclair et al., 2013). Female terminalia telescoping, with long membranous section posterior to segment 7; three spermathecae.

Type Species: I. nigromaculata White.

Comments: There are three species of Ironomyia, all Recent, the other two species besides the type being I. francisi D.K. McAlpine and I. whitei D.K. McAlpine. The genus is distributed in eastern Australia from Queensland to Tasmania (McAlpine, 2008). According to McAlpine (2008) these flies are uncommon, usually found on tree trunks, sometimes attracted to lights. Their life histories are unknown.

Palaeopetia Zhang, 1987: 595.

Sinolesta Hong and Wang, 1988 (synonymy by Mostovski, 1995). Type species S. lata (Hong and Wang).

Diagnosis: Vein Sc fused to R₁ for most of their lengths; pterostigma (between apices of Sc and R₁) well sclerotized; M₁-M₂ forked, with short stem connected to apex of cell d; crossvein dm-cu perpendicular to longitudinal veins (not oblique). As seen in at least the two species in Burmese amber: pedicel without fingerlike lobe; flagellomere 1 with distinctive seam on lateral and mesal surfaces; wing membrane largely glassy, with microtrichia only at trailing margin of wing; acrostichals numerous, scattered, as in Cretonomyia (not in 2 rows as in Ironomyia); scutellar setae larger than in Ironomyia; thorax with 4 notopleural, 1 large pair dorsocentral, 1–2 large postalar setae; midleg with large stiff setae, 1 on femur, 3–5 on tibia.

Type Species: P. laiyangensis Zhang, 1987. Early Cretaceous, China (compression).

Comments: There are nine species of Palaeopetia described thus far, all of them compressions from the Cretaceous. Besides the type species the others are the following: P. lata (Hong and Wang) (Early Cretaceous, China); P. tertia Mostovski, P. volacris Most., P. longisaetigera Most., P. mina Most., P. commemorabilis Most., P. armata Most., P. bellula Most., P. asaetigera Most. (Cretaceous of Eurasia and Siberia). These species were diagnosed largely on the basis of subtle differences in wing vein proportions (Mostovski, 1995b), nonetheless suggestive of significant past diversity of ironomyiids. I have examined some of the specimens described by Mostovski (1995b), including all of the types.

The amber species reveal the plesiomorphic nature of the genus, which appears to be a sister group to all other fossil and living ironomyiids based on the antennal structure and retention of some microtrichia on the wing membrane (fig. 37). Even though Palaeopetia dorsalis, n. sp., and P. terminus, n. sp., are known only from opposite sexes, it is very doubtful that the species differences are sexually dimorphic, given especially the positions of the arista, setation of the thorax, and microtrichial patterns on the wing.

Diagnosis: Differs from P. terminus, n. sp., also in Burmese amber, by smaller size, wing shorter and broader (L/W 1.77, vs 1.89), with microtrichia covering more of the wing membrane; arista situated dorso-preapically (vs. terminal); 1 (vs. 2) postalar seta; posteriormost notopleural seta slightly longer than others (vs. 2x the size); anteriormost scutellar seta nearly equal in size to adjacent one (vs. 0.3x the size); hind tibia with dorsal row of 3 strong setae (vs. 6, alternating with smaller, thick setae).

The Burmese amber species of Palaeopetia can be separated from all the compression-fossil species by the following venational differences: apical separation of Sc and R₁ ca. 0.5x their length (i.e., these two veins fused for greater distances in the amber species); cell cup is slightly shorter and wider, the apex less acute.

Description (based on unique female): Head: Eyes large, occupying most of dorsal and lateral portions of head, female dichoptic; eye bare, no differentiation of facets. Female frons: relatively narrow, sides parallel, width approximately equal to distance between outer margins of posterior ocelli; frons glabrous, without setae, possibly without setulae (obscure); presence/ absence of median furrow obscure. Ocelli well developed, raised above frons but not tuberculate; no ocellar setae; 2 short postocellars present. Occiput broad, gently and largely concave, lateral and dorsal margin near eye and vertex rimmed on each side with ca. 25 stout, stiff, flattened setae, lengths 6–8x diameter of eye facet. Occipital foramen very large, width ca. 0.3x occiput width. No vibrissa or genal setae. Antenna: Scape subcylindrical, short, with transverse row of 3 stout, black setulae dorsally; pedicel very short, rimlike, dorsal margin with row of 5–6 stout, short setae. Basal flagellomere large, laterally flattened, roughly drop shaped, with long groovelike seam on inner (mesal) surface, shorter seam on lateral surface, plus some apparent foveae (sacculi, sensu McAlpine, 2008). Arista bare; attachment dorsal-preapical, slightly lateral (not on dorsal edge), 3-articled, basal 2 articles small; total arista length 2.5x that of basal flagellomere. Mouthparts: Short, barely protruding beyond oral margin; palp 1-segmerited, extended slightly past labellum; labellum small, prementum and clypeus not observable. Thorax: Brown, notum slightly convex (not dome shaped) in lateral view. Acrostichals numerous, fine, evenly scattered on notum (not in rows). One pair of dorsocentral setae, stout, close to scutellum, length ca. equal to that of apical scutellar setae; distance between dorsocentrals slightly greater than length of dorsocentral. Prescutellum well developed, lenticular, width almost equal to that of scutellum base. Scutellum with 4 pairs stout marginal setae, increasing in length apicad, apical pair upturned and slightly cruciate; dorsal surface of scutellum without fine setulae. One very long postalar seta, length ca. 1.8x the dorsocentral. Notopleural setae in row of four (entirely preserved on right side). No pleural setae present; prosternum not observable. Wing: Membrane entirely hyaline, no markings or infuscate areas; microtrichia absent except at wing margin between tips of R₂₊₃ and CuA₂+A₁. Wing short, broad, L/W 1.77 (from tip of wing to level of crossvein h). Vein C ends at tip of R₄₊₅. Sc long, joined to R₁ for 0.65x its length, separated at base and at apex, membrane slightly darkened between apical fork of Sc and R₁. Stem of Rs short, fork of R₂₊₃-R₄₊₅ long, apices of Rs veins straddling tip of wing. Crossvein br-m very short, cell d present, L/W 3.6, apically truncate (not acute) (dmcu perpendicular to M₂ and CuA₁). Basal cells bm and cup closed; cell cup triangular; vein CuA₂+A₁ complete, reaching wing margin; A₂ present, incomplete, anal lobe very shallow. Legs: Metafemur and metatibia slightly longer and thicker than in other two pairs of legs. Basitarsomere on all legs approximately equal in length to remaining, distal tarsomeres. All coxae with 2 setae (ventral on fore- and midlegs, dorsal on hind legs). Pro- and metafemur without setae; mesofemur with long, stout seta on anterior surface, ⅓ from femur apex. Protibia with short middorsal seta, 2 apical setae (lengths ca. equal to width of tibia). Mesotibia with 4 long setae: 2 midlength (anterior and posterior surfaces), 2 apical. Metatibia with 2 stout, long, lateral setae, row of 4 shorter fine ones on dorsal edge; 1 large ventroapical seta plus several smaller ones. Metabasitarsomere slightly expanded. Pretarsal claws well developed, strongly curved; pulvilli well developed, slightly shorter than claw; empodium not visible (probably small and setiform). Abdomen (female): Length ca. equal to that of head + thorax, width slightly greater than thorax; tapered apicad. Eight well-developed tergites visible, none with macrosetae, covered overall with decumbent setulae, no apparent color/pruinescence patterns; tergites extend laterally over pleural membrane. Sternites well developed, broad, lateral margins nearly touching tergites, 7 sternites visible (first one probably small, hidden). Female Terminalia: Largely membranous; terminal sternite (8?) divided medially into 2 small oval sclerites; hypoproct well developed, apically pointed; cerci well developed, 1-segmented, cercus broad, with apical half darkly pigmented. Spermathecae not visible.

Specimens Examined: Holotype, female, AMNH Bu-FB34, in Burmese amber. In good condition, largely well preserved except for loss/ damage of portions of thorax.

Etymology: In reference to position of the arista on the basal flagellomere.

Diagnosis: Distinguished from P. dorsalis, n. sp., as given in the diagnosis above.

Description: Very similar to P. dorsalis with the exception of the following features: Head: Antenna with arista terminal, not dorsal-preapical. Male eyes large, holoptic for length of approximately 8 facets; ocellar triangle and small portion of frons exposed; no differentiation of facets; ocelli on low tubercle, close together. Thorax: Posteriormost notopleural seta very long and robust, ca. 2x the length and width of other notopleurals; 2 (vs. 1) postalar setae (anterior one finer). Transverse suture well developed. Anteriormost scutellar seta very small, length less than 0.3x that of adjacent scutellar seta (vs. approximately equal in size). Legs: Hind tibia with dorsal row of 6 stout, slightly curved setae, alternating with smaller stout setae. Wing: As drawn: longer, L/W 1.89 (vs. 1.77), from tip to level of crossvein h. M₁ slightly more arched; microtrichia confined to wing margin. Terminalia: Epandrium glabrous, brown, apparently heavily sclerotized; laterally flattened (clamlike), with fine setae on inner edge; surstylus pendulous, setulose, curved and clavate, apparently articulating with ventrolateral portion of epandrium (not fused). Aedeagus and paraphallic structures not observable.

Specimens Examined: Holotype, male, AMNH Bu-SE2/6, in Burmese amber. In excellent condition.

Etymology: In reference to the position of the arista on the basal flagellomere.

Diagnosis: Eyes virtually touching dorsally in male; antennal pedicel with fingerlike lobes extended into basal flagellomere on mesal and lateral surface; wing with membrane entirely glassy (no microtrichia); veins M₁ and M₂ with short to long stem (not connected directly to cell d); anal lobe of wing shallow; acrostichals numerous and scattered, not in rows.

Type Species: P. gibbera, new species.

Etymology: Pro- (first), and -ironia (from Ironomyia), in reference to the stem-group position of this extinct genus relative to Ironomyia. The genus name is feminine.

Comments: The new genus is a stem group; it does not appear to have any features that are apomorphic with respect to Ironomyia and Cretonomyia (fig. 37). It seems preferable to have a separate genus for these two species, rather than expand the definition of the extant genus Ironomyia, which is quite apomorphic. Also, despite the list of differences between the two species, given in the diagnosis immediately below, they are actually quite similar. The most significant differences appear to be the orientation of crossvein dm-cu and length of M₁-M₂ stem.

Diagnosis: Differs from the other species of the genus, also in Burmese amber, by the following: Head broader, concavity of occiput not nearly as deep; pedicel lobe long, more fingerlike, extended >0.5x the length of basal flagellomere (vs. less than this, lobe more triangular); notopleural, postalar setae shorter; thorax deeper, scutum more dome shaped (vs. slightly flattened on top); pro- and mesocoxae not setose (vs. with dense, fine setae); mesofemur with longitudinal groove, nearly length of femur (vs. without); wing with costal edge convex (vs. flat), apical fork of Sc-R₁ larger; apex of wing broadly rounded (vs. acute); fork of M₁-M₂ with very short stem; crossvein dm-cu oblique to M₂ and CuA₁ (vs. perpendicular).

Description: Head: Rather broad, depth/ width 0.66. Occiput near posterior margin of eyes rimmed with row of stiff, whitish setae. Eyes: Bare, fully separated in female by distance slightly greater than outside width of lateral ocelli; no differentiation of facets. Frons: Dark brown, largely bare, with a few fine, scattered, minute setulae; lateral margins parallel, modest emarginations around bases of antennae; median furrow present, faint; no ocellar, postocellar or frontal setae present. Face below antennae relatively short; oral cavity exposed anteriorly; clypeus broad but narrow; oral margin rimmed by protruding membrane. Vibrissa absent. Antenna: Bases very close, oval; scape very small, conical; pedicel with fingerlike lobe inserted into lateral and mesal surfaces of basal flagellomere; basal flagellomere subcircular, laterally flattened; arista terminal, with 1 or 2 small basal articles (not clearly observed); arista bare. Mouthparts: Compact, not protruding beyond level of basal flagellomeres. Palp small, globular, light in color; labellum small, laterally flattened, extended slightly beyond level of palps. Thorax: Very deep, depth ca. 1.1x the length; scutum arched, almost hemispherical in profile. Scutum with scattered, very fine, decumbent setulae (barely visible); one pair of dorsocentral setae, short, stout, very close to anterior margin of scutellum; scutellum with 4 pairs of short, stout setae; 4 notopleural setae, located just above pleural cleft and anterior to transverse suture; 2 postalar setae; prescutellum well developed, lenticular. Wing: Relatively broad, width/length 0.51, apex broadly rounded, anterior (costal) edge convex (not flat); membrane entirely glassy, no microtrichia (even near wing margin). Vein C ends at apex of R₄₊₅. Sc long, fused to R₁ for 0.62x its length, both veins free at base and apex. R₂₊₃ and R₄₊₅ long, nearly parallel; crossvein br-m very short; cell d long and narrow (L/W 5.55), apex acute (crossvein dm-cu oblique). M₁ and M₂ joined at base by very short stem connecting to cell d; cell cup narrow, apex acute. A₁, A₂, anal lobe and alula not entirely visible.

Legs: Slender. All coxae with a few, fine, light setae; femora without macrosetae. Protibia with thick, short, preapical seta on mesal surface, ca. 10 short transverse, ctenidial-like rows of fine setae, apical row long and comblike; tarsomeres 1–4 with short ctenidial combs. Mesofemur with narrow but well-defined longitudinal groove on ventral surface (nearly length of femur), to which tibia must fit against. Mesotibia with minute, spurlike lobe on ventral surface, spurlike ventroapical sea; tarsomeres 1–4 with short rows transverse ctenidia. Metatarsus same as mesotarsus. Pretarsus with claws well developed, pulvilli slightly shorter than claws; empodium setiform.

Abdomen: Relatively short, tapered apicad; with fine, short, scattered setulae on tergites and sternites, no macrosetae. Eight tergites and 7 sternites visible, well developed, narrow pleural membrane exposed. Dorsal margin of tergite 7 very short, hidden beneath posterior margin of tergite 6. Cercus 1-segmented. Female Terminalia: Largely retracted, not visible.

Specimens Examined: Holotype, female, AMNH Bu-SE07, in Burmese amber. In excellent condition.

Etymology: From Latin gibber (L., “hunched”).

Diagnosis: Distinguished from its congener as given in the diagnosis above.

Description: Head: Depth/width 0.92. Occiput near posterior margin of eyes rimmed with row of stiff, whitish setae that point backward. Eyes: Bare; meeting dorsally (or virtually so) for distance ca. 8 facets; no differentiation of facets; medial edges emarginate around eyes. Frons: A barely exposed sliver, dark brown; faint median furrow present on dorsal sliver of frons; medial edges emarginate around antennae; no ocellar, postocellar, or frontal setae present. Ocellar triangle raised; lateral/posterior ocelli closer to each other than to anterior ocellus. Face below antennae very short; oral cavity partly exposed anteriorly; clypeus narrow, Ω -shaped; oral margin not rimmed by protruding membrane. Vibrissa absent. Antenna: Bases very close, scape small, short and funnel shaped; pedicel with triangular lobe inserted into lateral and mesal surfaces of basal flagellomere, lobe not quite 0.5x length of basal flagellomere; basal flagellomere subcircular, laterally flattened, dorsal third light, ventral 2/3 darker, brown; arista terminal, with 2 small basal articles, length of each article ca. 2x its width; arista bare. Mouthparts: Compact, not protruding beyond level of basal flagellomeres (as preserved). Palp small, globular, light in color; labellum small, laterally flattened, extended slightly beyond level of palps. Occiput dark brown, dorsal portion deeply concave. Thorax: Depth ca. 0.95x the length; scutum convex in profile, slightly flattened on top. Scutum with scattered, very fine, very decumbent setulae (most visible laterally). One pair of dorsocentral setae present, stout and short, length slightly less than length of scutellum; very close to anterior margin of scutellum. Scutellum with 4 pairs of short, stout setae, apical pair upright with tips crossing; 4 stout, stiff notopleural setae, located just above pleural cleft and anterior to transverse suture; 2 postalar setae; prescutellum well developed, lenticular. Wing: Width/length 0.48, apex slightly acute, anterior (costal) edge virtually flat; membrane entirely glassy, no microtrichia (even near wing margin). Vein C ends at apex of R₄₊₅. Sc long, fused to R₁ for 0.77x its length, both veins free at base and apex. R₂₊₃ and R₄₊₅ long, nearly parallel; crossvein br-m very short, cell d L/W 3.0, apex square (crossvein dm-cu perpendicular to longitudinal veins); M₁ and M₂ joined at base by stem connecting to cell d, stem 0.21x length of stem + fork; cell cup narrow, apex acute. A₁, A₂, anal lobe and alula not entirely visible. Legs: Slender, brown, pro- and mesocoxae with sparse brush of ca. 10 fine, long setae ventrally (metacoxa bare); femora without macrosetae. Protibia with thick, short, preapical seta on dorsal surface, ca. 8 short, transverse, ctenidial-like rows of fine setulae, tarsomeres 1–4 with short ctenidial combs. Mesofemur without longitudinal groove on ventral surface. Mesotarsomeres 1–4 with 2 longitudinal rows small, stout setae on ventral surface. Metatarsus same as protarsus. Pretarsi with claws well developed, pulvilli shorter than claws; empodium setiform, fine and projecting. Abdomen (Male): Relatively short, base thick; with fine, short, erect, pilelike setulae on tergites, no macrosetae. Tergites large, covering most of lateral surface of abdomen; dark brown. Six well-developed tergites visible (sternites not exposed); narrow pleural membrane exposed. Epandrium large, bulbous, ventroflexed, tucked under tergite 7. Male Terminalia: Not exposed.

Specimens Examined: Holotype, male, AMNH Bu-Se2/8, in Burmese amber. Complete, very well preserved.

Etymology: In reference to burmite, a common term for Burmese amber.

Hennigophora Brown, 2007a: 8. Type species Archiphora robusta (Meunier) (Baltic amber, fig. 19).

Diagnosis: (From Brown, 2007a, with modifications in parentheses): Basal flagellomere of male relatively small (little differentiated from female); frons large, with frontal setae as in Archiphora patagonica (which has 1 pair interfrontal setae, 1 pair orbitals) (fig. 46B); scutum with large setae consisting of 1 median acrostichal row and 1 dorsocentral row on each side (fig. 19); stem of M₁ and M₂ well developed (tubular, but not sclerotized; fig. 46B); anal lobe small; empodium absent; (stridulatum present); male terminalia with separate surstylus on left side.

Comments: Brown (2007a) placed Hennigophora robusta, Ulrichophora lobata, and “Archiphora” pria in a polytomy with Archiphora patagonica and Sciadocera rufomaculata. Based on the discovery of a new specimen of A. pria, which is better preserved than the original specimen/holotype (AMNH NJ-773), I am transferring this species to Hennigophora, though this is essentially based on plesiomorphic resemblance.

Archiphora pria Grimaldi and Cumming, 1999: 97.

Summary: The original (holotype) specimen of H. pria is covered with a milky coating that obscures many surface details, critically the acrostichals, as well as the presence/absence of a median furrow on the frons, and terminalia, though portions of larger macrosetae protrude through the coating. A new specimen in New Jersey amber, AMNH NJ-Ch1, has some critical features that are better preserved, but this specimen lost the left side of the head and thorax before or during fossilization, and the abdomen has a thin milky coating. A few acrostichals can be seen in left profile, which appear to be in one (or possibly several) rows and are significantly smaller than those in H. robusta (whose acrostichals are about as large as the flanking dorsocentrals; fig. 19). Male genitalic structure cannot be compared to H. robusta since this specimen is female. Most importantly, the stridulatum is present in AMNH NJ-Ch1, with a scraper very visible on the mesal surface of the right profemur, and a file on the lateral surface of the left procoxa. The location, arc, and length of the stridulatum are just as in living sciadocerines, but the number and structure of ridges and teeth are not visible. A stridulatum was also observed in H. robusta based on a file on the right procoxa of a male specimen, AMNH Ba-JH58 (fig. 19) (this specimen also lacks a median furrow on the frons).

Hennigophora pria is similar to H. robusta in venation (proportions and lengths of main veins, a tubular stem of M; fig. 47A, B), setation of legs; and a broad frons (judging from the preserved right half in AMNH NJ-Ch1). It differs from H. robutsa by having a pair of reclinate interfrontals, near the frontal margin of the frons (vs. absent); also, setae are shorter, especially the acrostichals, supraalars, postalars, and scutellars. In agreement with Brown (2007a), Archiphora should be restricted to the sole living species.

Eosciadocera Hong, 1981: 140. Type species E. helodis Hong, 1981 (Fushun amber).

Diagnosis: (from Brown, 2002, with modifications) Largest phorids, body lengths 6–7 mm; with many very large, bristlelike setae; frons narrow; 1–4 pairs frontal setae; size of basal flagellomere with little or no sexual dimorphism. Acrostichals, dorsocentrals, postoculars (even setae on tegula) large, thick macrosetae; proepisternum very bristled (10–20 setae). Branches of M₁ and M₂ tubular, not sclerotized; these veins not completely connected. Wing membrane with dense microtrichia overall; proleg stridulatum present; frontal sulcus absent.

Type Species: E. helodis Hong, in Early Eocene amber from Fushun, China. Unfortunately, the collection of Fushun amber insects studied by Hong is lost, including the types, and additional specimens of Eosciadocera have not been found in new excavations of Fushun amber (Wang et al., 2014). It is necessary to rely on the original description.

Comments: There are now three species of Eosciadocera: E. helodis in Fushun amber, E. setosa Brown in Baltic amber (fig. 15), and E. pauciseta, n. sp., also in Baltic amber (fig. 16). The flies are extraordinarily large and bristly, almost like calyptrates, and apparently very rare in Baltic amber. Brown (2002) expressed some doubt about the sciadocerine position of the genus, but later included Eosciadocera in this subfamily (Brown, 2007a). Courtesy of Christel Hoffeins, who loaned the paratype of E. setosa (CCHH 1358-1: fig. 15), I was able to observe the stridulatum in this species. There are considerable differences between the two Baltic amber Eosciadocera species (listed in the diagnosis below), but I am placing the new species in this genus given the striking similarities between the two, such as the uniquely large size and numerous, large macrosetae.

Diagnosis: Similar to Eosciadocera setosa, also in Baltic amber, by the very large body size (6–7 mm), protibia with only a ventroapical macroseta; one large pair of vertical setae; pair of small (divergent) postocellar setae; basal flagellomere subspherical; 1 to several rows of large acrostichals; proepisternum with many large setae; and anepisternum without large setae. Proleg with stridulatum. Differs from E. setosa by the following: two (vs. four) pairs fronto-orbital setae; frons broad, greater than ½ head width (vs. ¼); palp relatively large, flat, with stout black setae on distal margin (vs. small, fine setae); proscutellum absent (vs. present); notopleurals 4 (vs.5–8); scutellars in two pairs (vs. 5–6 pairs); metafemur without macrosetae (vs. 5–6 long ones).

Description: Large, ca. 6.7 mm body length; color appears brownish overall, with thick, black macrosetae. Head: Eyes well separated, bare, no differentiation of facets, no emarginations. Frons without median sulcus, broad (ca. 0.65x width of head), length (from anterior ocellus to anterior margin) shorter than width. Ocellar triangle approximately in middle of dorsum of head (including frons). Frontal setae: two pairs frontoorbitals (posterior pair lost, but sockets visible), situated near middle of frons length; ipsilateral fronto-orbitals separated by distance ca. 5x diameter of fronto-orbital seta socket. Supraantennal interfrontals possibly absent (or just lost in specimen). One pair of vertical setae present (setae lost, but sockets visible), situated midway between posterior fronto-orbital and row of postocular occipital setae. Ocellar setae: 1 pair (lost, but sockets visible, apparently large); postocellars minute, fine, length slightly greater than diameter of ocellus, located between posterior ocelli. Occiput just behind posterior margins of eye with 19–20 long, stout postocular setae; 7–8 additional large occipital setae mesal to this row. Face deeply concave, with very thin vertical carina, flanked by pair of recessed areas (fossae) for antennae. Vibrissa absent. Antenna: Scape very narrow, ringlike, no setae; pedicel short, conical, no setae. Basal flagellomere subspherical (length slightly greater than width), covered with short, velvetlike pile. Arista dorsal; 3-merous, basal two articles short (lengths ca. 2x their widths). arista micropubescent. Mouthparts: Oral margin protruding, such that oral cavity faces forward, surrounded by short sleeve. Palp large, flattened, distal margin with thick, short setae. Labellum fully recessed into oral cavity (as preserved); opened lobes nearly forming circle, pseudotracheae not visible, though minute microtrichia are.

Thorax: Heavily bristled; scutum gently arched; proscutellum absent or very reduced; prosternum large, fully exposed, bare. Acros - tichals large, in even central row of ∼10 setae; row of ∼10 dorsocentral setae lateral to acrostichals (setae in both rows about same size). Other thoracic setae: 1 large postpronotal; oblique row of 6 supraalars (1 very large); 1 large postalar; 4 large, presutural notopleurals; 6–7 large proepisternals (rest of pleuron without setae). One pair of large dorsocentrals, sockets slightly lateral to line formed by outer row of acrostichals; 2 pairs of large scutellars (lengths very similar), apical scutellars very close. Wing: Very long, ca. 8 mm, nearly twice length of abdomen. Membrane of wing clear, no infuscation, entirely covered with microtrichia. Tegula bristly, with 7–8 thick setae; basicosta with row of 4 large setae; vein h thick; Sc thick, fused to R₁ at 0.30x length of R₁; C with 2 rows thick spinules, vein ends at apex of R₄₊₅; R₂₊₃ ends midway between apices of R₁ and R₄₊₅. Vein R₄₊₅ ends well before apex of wing, fully fused to C. Base of M₁ lost, evanescent, apex of M₁ ending at wing tip; M₂ complete, including base. Cu veins complete; anal vein present, incomplete. Cell r-m complete (closed basally); cell dm slightly opened basally and distally; cell cup present, apex of CuA₂ not fused to A₁. Alula small, with fringe of 10–12 stiff, nonfeathered setae. Legs: Pretarsi with curved bristle near where empodium would be (as in Ironomyia); tarsomeres 1–4 with hair seam on mesal surface, 2 longitudinal rows of dark, small, spinulelike setae ventrally. Foreleg: Coxa heavily setose overall, with >30 thick, large macrosetae; femur without macrosetae; stridulatum present, “scraper” exposed on bare, light patch at base of inner surface of right fore femur, with about 12 minute ridges; tibia with only ventroapical macroseta, no others. Midleg: coxa setose, ca. 10 setae; femur without macrosetae; tibia with 2 middorsal setae, 4 apical ones. Hind leg: coxa with a few fine setae; femur with single ventrolateral macroseta; tibia with pair of middorsal macrosetae, plus 4 apical ones. Abdomen (female): Sternites well developed; apical segment with longer, thicker setae; pair of long, fine setae just above cerci (on epiproct?); cerci short, pointed downward, setose.

Specimens Examined: Holotype, female, AMNH Ba-JVe565, in Eocene Baltic amber. The specimen is complete, but portions of it are covered in milky coating or are obscured by fractures.

Etymology: From Latin paucus (“few”), in reference to its fewer setae compared to setosa.

Diagnosis: Proleg stridulatum present (seen in holotype specimen only); frons with well-developed median sulcus, one pair of fronto-orbital setae in both sexes; one pair of interfrontals in male, 3 pairs in female; one pair of verticals in male, two pairs in female; basal flagellomere not sexually dimorphic in size; one pair of dorsocentrals, two pairs of scutellars present; sternites well developed in male, lost in female except for terminal two sternites (7 and 8); lacking wing-vein characters of Euphorida (i.e., chars. 19–24 in table 4, fig. 43).

Type Species: P. dimorion, n. sp.

Etymology: Pro- (“first, before”), and -phora, common suffix for generic names in the Phoridae. The name is feminine.

Comments: The possession of a sulcus on the frons and great reduction in female sternites (which occur in stem-group and many crowngroup Euphorida), but more generalized venation of the Sciadocerinae, makes the phylogenetic position of this genus apparently close to the basal fork of the two lineages.

Diagnosis: As for genus, by monotypy.

Description: Based on both sexes. Body length 1.8 mm; setae not feathered. Head: Eyes large, well separated even in male, occupying entire lateral portions of head; bare, no differentiation of facets; margins entire. Frons: Parallel sided, with well-developed median sulcus. Frontal setae: 1 large pair of fronto-orbital setae in both sexes, midway between interfrontals and verticals; 1 large pair of reclinate interfrontals in male, 3 pairs in female (anterior two pairs smaller); 1 large pair of vertical setae in male (2 pairs in female); 1 large pair of upright ocellar setae (sockets in middle of triangle) in both sexes; postocellars ca. 0.65× length of ocellars, slightly divergent. No vibrissa. Occiput near posterior margin of eye with row of fine setae, decreasing in size ventrad. Antenna: Scape very thin, ringlike; pedicel small, conical, inserted into basal flagellomere on mesal surface of flagellomere; basal flagellomere small, short ovoid; arista dorsally situated, 3-articled, basal 2 articles very short; terminal article of arista long (greater than width of head), micropubescent. Mouthparts not fully observable. Thorax: Short, stout, dorsum gently to moderately arched. Proscutellum present, well developed, lenticular, prosternum large, exposed, bare. Setae: 1 central row of ca. 10 long, fine acrostichals; row of similar setae on each side of acrostichals, anterior to dorsocentrals, shorter row lateral to these; all setae in rows decreasing in length anteriad. One large pair of dorsocentrals present; 1 large supraalar; 1 large postalar; 1 large postpronotal; row of 4 large, presutural notopleurals; 2 pairs of large scutellars (apical pair slightly longer). Pleuron without setae. Wing: Very similar in shape and vein proportions to Hennigophora robusta; membrane with microtrichia at posterior margin only. C with short spinules, widely spaced (distance between each greater than length of spinule). Tegula with row 4 strong setae on posterior margin, basicosta with 4 setae; details of wing base with poor visibility due to preservation (e.g., development of M stem, basal cells). R₄₊₅ relatively short; anal lobe relatively well developed (as in Hennigophora); alular setae long, not feathered. Legs: All pretarsi with empodium either absent or so reduced as to be unobservable at 200×; tarsomeres 1–4 with setulae in longitudinal rows, hair seam on mesal surface. Foreleg: coxa with minute, fine setulae overall; row of 6 large setae on ventrodistal margin; coxa widely separated, by distance approximately equal to thickness of coxa. Femur: Stridulatum present (as seen in male holotype: 11 scalelike teeth of scraper observed on left profemur; file not observable; no large setae on profemur. Protibia without large setae. Mid- and hindlegs: coxa with several large setae on posterior margin; femur without large setae; tibia with 1 large ventroapical seta, several smaller ones partially encircling tibial apex. Abdomen: Tergites well developed in both sexes; at least 3–4 large anterior sternites present in male (more posterior ones obscured), female with all but two terminal sternites (7 and 8) lost. Male Terminalia: Epandrium exposed, well developed, with ventral lobe (has broad attachment); surstylus articulating with lobes (not fused), clavate, pendulous. Ventral epandrial lobes, surstyli, periphallic appendages asymmetrical. Female Terminalia: Largely obscured; abdominal segments 7 and 8 much smaller than anterior ones, terminalia do not appear telescoped; hypoproct well developed.

Specimens Examined: Holotype, male, AMNH Bu8783; paratype, female, JZC Bu242, both in Burmese amber, well preserved, complete.

Etymology: From Greek, di- (“two”) and morion (“parts” in genitive plural) in reference to sexual dimorphism of the head setation.

Comments: Differences between the holotype male and paratype female are attributed to sexual dimorphism, otherwise the two specimens are very similar: body size and proportions, identical setation of the thorax, proportions of the wing veins, even the widely spaced costal spinules. Differences are the frontal setation, with the female having 2 additional pairs of small interfrontals (vs. 1 pair in the male), and a pair of inner verticals. Also, the female has only two small sternites (7 and 8); the male has well developed ones. Head setation is sexually dimorphic in living sciadocerines; likewise for the development of abdominal sternites in some basal Euphorida.

Summary: A unique male specimen (AMNH Bu-1376) of a minute species (∼1.7 mm body length), which is not being formally described since critical structures are not visible (i.e., arrangement of frontal setae, palp size, empodium, presence/absence of stridulatum, base of M vein). This species is like Prophora dimorion in appearing to have a frontal sulcus (this is barely visible), acrostichals in single row, 1 pair of large dorsocentral setae (vs graded row), 2 pairs of scutellars, presence of proscutellum, and few leg macrosetae. It differs from Prophora by significantly smaller size; head with finer, shorter frontal setae; 2 (vs. 3–4) pairs of notopleural setae; scutellar setae upright (vs. posteroclinate); no postalars (vs. 1); microtrichiae completely absent from wing membrane (vs. with some at apex); base of M appears spectral, though not fully visible (vs. present, tubular, though not sclerotized). Further, the male abdomen and genitalia are substantially different: in Bu-1376 segments 6–7 with constriction between them, tergite 7 bulbous, epandrium asymmetrical (vs. symmetrical in Prophora); male terminalia very asymmetrical, surstyli apparently absent or so small as to not be visible (vs. symmetrical, with pendulous surstyli).

General Description: Body short, length ∼1.7 mm total length, broad, with relatively few setae. Head about same width as thorax. Antenna with arista dorsal, preapical. Head setae barely visible, appears to have 1 small pair of supraantennal interfrontals; 1 large pair of orbitals; 1 pair of ocellars; 1 pair of verticals; postoculars relatively short. Scutum arched, short; 1 short row ∼6 acrostichals; 7–8 dorsocentral setae, not graded (1 large pair of prescutellar dorsocentrals; other dorsocentrals small, about same size as acrostichals). Two long notopleural setae, 1 supraalar, no postalars. Proscutellum present, narrow; scutellum short, wide, with 2 long, upright pairs of setae. Pleural region not visible. Wing short, broad (L/W 1.7), venation very similar to that of Hennigophora robusta, except that base of M appears spectral, not tubular; membrane devoid of microtrichia. Abdomen very short and broad at anterior end, width of segments 2 and 3 about same as thorax; abdomen tapered in width to segment 6 (= 0.25× width of segment 2), forming constriction between segments 6 and 7. Tergite 7 slightly asymmetrical, larger than tergite 6; tergite 9 (epandrium) well developed on right side; terminalia asymmetrical, shifted mostly to right (component structures not discernable); surstylus not apparent. Legs with very few macrosetae; mesotibia with apical pair of long, spurlike setae.

The specimen is largely complete, but some legs and segments are disarticulated. It is in a dark piece of amber that also contains a layer of sand grains, stellate trichomes, and particulate debris. A piece of bark or plant fragment lies under the fly; this and the sand grains prevent viewing the front of the head, prolegs, and some other areas.

Diagnosis: (male only). Extensively holoptic; arista dorsal; mouthparts small, clypeus minute; scutum and scutellum with numerous scattered setulae, two pairs of prescutellar dorsocentral setae, notopleural setae, four pairs scutellar setae. Vein r-m at level of Sc apex; M with short apical fork, M₁ not connected to R₄₊₅; dm and cup cells very large; alula small; spurious vein and sc-r lacking; male abdominal segments 6–8 very asymmetrical, epandrium to left side, sternite 8 terminal and bulbous.

Type Species: P. thompsoni, n. sp.

Etymology: From Latin pro- (“first, before”), in reference to the stem-group position of the fossil among Syrphidae.

Comments: Prosyrphus is a stem-group Syrphidae (fig. 51). It has a large cell bm (∼⅓ length of wing), apex of CuA₁ incomplete (not reaching the wing margin), cell cup large, and male genitalia that are very asymmetrical with a bulbous, terminal sternite 8 (among other genitalic features). Based on the unique male, features of the frons (e.g., lack of macrosetae) cannot be determined. Moreover, the body is stout and short; wing shape broad and apically tapered, the body overall with few macrosetae, and the mesal surface of the pedicel has a tonguelike lobe inserted into the basal flagellomere, features consistent with many modern syrphids.

Prosyrphus lacks synapomorphies of crowngroup Syrphidae, namely: a large alula, sc-r and spurious veins, M₁ curved upward to meet R₄₊₅ preapically; M₂ lost (or at most a spur on the curvature of M₁). Kovalev (1979) reported a fragmentary specimen of a syrphid or syrphoid in Late Cretaceous Siberian amber, but the characters are too few for a definitive attribution, and it may no longer be available for study since many of the Siberian amber specimens at the Paleontological Institute in Moscow have disintegrated. Otherwise, Prosyrphus appears to be the most derived dipteran known from the Mesozoic, although I predict that syrphids more derived than Prosyrphus will eventually be found in the Late Cretaceous, especially in the Maastrichtian and Campanian.

Diagnosis: As for genus, by monotypy.

Description: (male only). Body stout, compact. Head: Broad, slightly broader than thorax, faintly compressed dorsoventrally. Eye completely bare of setulae; large, occupying all of dorsal and lateral surfaces and much of venter; dorsal facets slightly larger than ventral ones, no discrete dividing line; male holoptic for entire length of frons. Frons obscured (presence/ absence of median furrow, interfrontal and fronto-orbital setae not determinable). Ocelli on low tubercle, with two small pairs of stiff ocellar setae. Vertical setae absent; postocular setae fine, small; occiput faintly concave, with scattered fine setulae. Face relatively broad, ∼0.3× width of head; bare, slightly swollen in middle; anterior tentorial pits deep, vertical and slitlike, close to eye margin. Oral cavity small, entirely ventral; vibrissa and genal setae absent. Antenna: Scape small, bare, slightly asymmetrical; pedicel asymmetrical, with tonguelike lobe inserted into mesal surface of basal flagellomere; arista dorsal; basal flagellomere reniform; arista with two minute articles at base, apical article long, flagellate, tapered to very fine apex, completely bare of micropubescence. Mouthparts: Clypeus minute; oval; isolated, not articulating with labrum; palp small, slender; proboscis, small, short, slender; labrum slender; labellum small, arely wider than rest of proboscis.

Thorax: Short, broad, deep in lateral view; scutum rounded but not arched. Acrostichals numerous, scattered, not in rows. Dorsocentral macrosetae present, in 2 prescutellar pairs, none in serial rows. Macrosetae: 2 supraalar; 5 notopleural; 4 pairs of scutellars, longest ones near center, disk of scutellum with setulae. Wing: Broad, length/width 2.0, tapered apicad; hyaline, slightly darkened between apices of Sc and R₁; membrane with dense, very fine microtrichia, less dense in cell Sc; pterostigma absent. Prehumeral costal seta(e) small, large macrosetae absent; vein C with minute spinules; end of C not visible (wing tips lost at surface of amber); Sc long, ∼0.6× length of wing; R₁ long, running close to base of Sc, slightly diverging apicad; sc-r appears absent; R₂₊₃ straight, base weak; R₄₊₅ straight; spurious vein absent; cell dm large, cleaver shaped; cell rm long, r-m at same level as apex of Sc; cell bm narrow; crossvein dm-cu close to wing margin, separated by distance ¾ length of dm-cu; M₁-M₂ forked, tip of M₁ not reaching wing margin; tip of CuA₁ not reaching wing margin; CuA₂ curved, A₁ straight; cell cup large, much longer than apical vein; anal lobe large, alula relatively small. Halter stem slender. Legs: Setose, relatively short, slender; femora longer than respective tibia, profemur with ventral row ∼7 long setae, setal lengths about equal to femur width. Mesotibia with short, stout ventroapical spur. Basitarsomeres longest of all tarsomeres; pulvillus ∼0.7× length of claw; empodium not observable (perhaps minute); claw ∼0.5× length of tarsomere 5.

Abdomen: Short, stout; anterior 4 tergites large, with short, scattered setulae, laterally curved but not contacting sternites (pleural membrane exposed). Five large sternites visible, anterior and posterior margins in contact; with short, scattered setulae. Male Terminalia: Segments 6, 7, and 8 asymmetrical, ventroflexed; sternites 5 and 6 exposed dorsally; sternite 8 bulbous, terminal; epandrium triangular, shifted to left; surstyli large, heavily setose; cerci symmetrical, setose, hidden beneath sternite 8, point forward.

Female Terminalia: unknown.

Specimens Examined: Holotype, male AMNH Bu-SE03 The specimen is in beautiful condition, very well preserved, and virtually complete (missing only the tips of the wings).

Etymology: Patronym for F.C. Thompson, for his many contributions to the systematics of Syrphidae and Diptera in general.

Diagnosis: Head lacking macrosetae, female frons pubescent; ptilinal suture absent; basal flagellomere large, tapered asymmetrically to apical point (which bears arista); scutum with numerous scattered setulae (none in rows); thorax with one pair of dorsocentral setae, one pair of of scutellars, three postalars, four notopleurals, no supraalars. Vein Sc long; apices of R₄₊₅ and M₁ converge closely at wing tip but do not meet; M forked, with very short stem; cells dm and cup very large. Metatibia with ventral pair short, stout apical spurs.

Type Species: A. burmensis, n. sp.

Etymology: Derived directly from Aschiza, and -myia (Greek, “fly”). The genus name is feminine.

Comments: The phylogenetic position of the genus is equivocal (fig. 51), having features of Syrphidae and Pipunculidae but decidedly more primitive than the crown group of either. Syrphid features include a short sc-r crossvein, apex of CuA₁ incomplete, the exposed female frons being pubescent (the head lacking any macrosetae), and the alula is well developed. Aschizomyia plesiomorphically has a small cell bm; C ends at the apex of M₁ (instead of R₄₊₅); M is forked, and M₁ does not join R₄₊₅ preapically. The venation is very similar to that of Protonephrocerus, but Aschizomyia lacks all the features of the head, female terminalia, and pretarsi that characterize Pipunculidae. The large cup cell occurs in both Syrphidae and Pipunculidae, possibly convergently. It is difficult to discern whether the arista is dorsally or apically situated on the basal flagellomere, since it occurs at the apex of a narrow, pointed lobe and the flagellomere is asymmetrical, with an extensive, emarginate ventral margin. I have chosen to depict Aschizomyia, preliminarily, in a basal trichotomy with Syrphidae and Pipunculidae + Schizophora because of the equivocal morphological evidence. The lack of a ptilinum indicates that Aschizomyia is not a schizophoran, though the possibility remains that it is a stem-group one.

Diagnosis: As for genus, by monotypy.

Description: (female only). Head: Hemispherical. Eye large, bare of setulae (portion of right eye missing); occupying all of lateral surface of head (cheek not exposed), margins flanking frons are parallel. Frons well developed, width slightly less than face; with fine, short pubescence only; no macrosetae on head (e.g., no interfrontals, ocellars, orbitals, verticals, or vibrissae). Occiput densely setose, with thick, short setae overall; occiput slightly swollen laterally, centrally deeply recessed. Oral margin slightly protruding dorsally. Ptilinum lacking. Antenna: Scape hidden (probably minute); pedicel asymmetrical, with ventral lobe; dorsoapical portion with stiff setae, having rounded condylelike “conus” inserted into base of flagellomere 1 (cuticle is cleared). Basal flagellomere large, laterally flattened, apex tapered and pointed; asymmetrically drop shaped in lateral view; arista attached to pointed apex. Arista with 2 minute basal articles; apical article long, fine, flagellate, bare (no micropubescence visible). Mouthparts: Clypeus protruding; narrow U-shaped, articulating with but not fused to oral margin. Palp relatively large, apex pointed, slightly longer than labellum; labellum flat, as preserved largely recessed into oral cavity and between palps; labrum not observable.

Thorax: Relatively flattened dorsally, not particularly deep. Prosternum (very exposed) cordate, entirely free, unconnected to surrounding sclerites. Scutum and scutellum covered in dense, short setulae (these thicker and longer on scutellum, especially lateral margins) (rows of acrostichals absent). Transverse suture very short, far anterior, just above notopleural setae. Thorax with following large macrosetae: 1 pair of large, prescutellar dorsocentrals; row of 3 postalar setae (posteriormost one very thick); row of 4 notopleural setae (posterior 2 largest, thickest; anterior one ∼0.5× size of others); anepisternum with dense, fine pilosity; katepisternum bare. Prescutellum absent; scutellum triangular in dorsal view, apex pointed, with pair of large, thick scutellar setae. Wing: Relatively slender, length 2.5× the width, apex narrow (not broadly rounded); no infuscation or darkening of membrane, even between Sc and R₁; membrane with fine microtrichia over entire surface. Row of 5 prehumeral costal setae; vein C with fine setulae (without thick/coarse spinules), C ends at tip of M₁ Sc relatively long, slightly greater than 0.5× length of wing; R₁ close and parallel to Sc, ends closer to apex of R₂₊₃; crossvein sc-r present, close to level of crossvein h. Apex R₂₊₃ slightly divergent from apex of R₄₊₅; apices of R₄₊₅ and M₁ converge closely at wing tip but do not meet. Cell dm very large; cell br long, slender, with small, incomplete, spurlike crossvein near base of CuA₁. Crossvein dr-m weakened in middle; no trace of spurious vein present; cell dm very large, crossvein dm-cu very close to wing margin. M₁-M₂ fork present, with very short stem attached to apex of cell dm. Apex CuA₁ incomplete (not reaching wing margin); cell cup large, with short apical vein; anal lobe present, small; A₂ present, complete; alula well developed. Halter relatively small.

Legs: Of moderate length and width. Proand mesocoxae short, mostly integrated into pleura; metacoxa slightly longer, suspended and largely free from pleura; pro- and mesocoxae with setae on distal margin. All podomeres setulose, with longer setae on some portions; profemur with irregular, ventral row 10–12 longer, fine setae; mesofemur with longer setulae on distal half. Tibial spurs 0-2-0, mesotibial spurs ventroapical, short, stout; apex of metatibia slightly swollen; basitarsomere length equal to length of tarsomeres 2+3 on all legs; claws large, pulivilli relatively small (≤0.5 length of claws); empodium setiform.

Abdomen: As preserved, dorsoventrally flattened; 6 tergites exposed, 1–4 large, all covered with dense, short, decumbent setulae (as on scutum); 6 sternites present, 1–4 large, well developed, width ∼0.7× width of abdomen. Pleural membrane exposed between lateral margins of sternites and ventral margins of tergites. Spiracles in membrane, close to margin of tergite. Male Terminalia: Unknown. Female Terminalia: Very simple; terminal segments apparently not telescoping; cercus small, oval, simple, 1 -segmented.

Specimens Examined: Holotype, female, AMNH Bu-SAl. The specimen is very well preserved, missing only the right eye and the tips of the left wing and metatarsi.

Etymology: In reference to the country of origin.

A cyclorrhaphan larva in Burmese amber, AMNH Bu-1536, is well preserved, complete, and has many structures preserved in detail. Length is ∼2.5 mm, body relatively slender. Body is visible dorsally and ventrally, though debris adhering ventrally obscures some details (e.g., creeping welts). Cuticle somewhat cleared, partially revealing cephalpharyngeal skeleton. Cephalopharyngeal skeleton (CPS) with dorsal and ventral cornus well developed, appear fully sclerotized, extend posteriorly to level of suture between segments 2 and 3. CPS dorsally with narrowly U-shaped epipharyngeal sclerite, which has multiple fine perforations. Mandibles appear simple, apparently lacking multiple small teeth on ventral margin or on broad lateral surfaces at base (as are found, for example, in Megaselia [Phoridae]). Body: Anterior two segments distinctly narrower than other, posterior segments. Apical structures of anterior spiracles not visible, not everted (though internal tracheal trunk visible). Dorsal and lateral portions segments 3–11 with short, stout, erect, exocuticular tubercles (each broadly conical with minute apical process); each segment with transverse row of eight such tubercles, bilaterally symmetrical, lateral ones pointing outward, dorsal ones pointing upward. Apical segment with ventralmost pair of tubercles small, very close; flanked by pair of larger, pointed tubercles, both pairs pointing backward; 2 lateral pairs present (one pair is dorsolateral), pointed laterad. Posterior spiracles not visible (this area obscured).

The body shape plus the presence and structure of transverse rows of tubercles is most similar to larvae in the Phoridae, though a well-developed, perforated epipharyngeal sclerite occurs in only some phorids (Ferrar, 1987). Phoridae have diverse mandible structure, some with heavily dentate mandibles, others lacking teeth. AMNH Bu-1536 is possibly the larva of either a prioriphorine (which are diverse and relatively common in Burmese amber), or one of the sciadocerines taxonomically treated here as adults. Three Cyclorrhapha larvae were reported in Late Cretaceous amber from New Jersey (Grimaldi and Cumming, 1999), all quite different from each other and from larva Bu-1536.

A small puparium in Burmese amber, JZC Bu304 (1.4 mm body length), is typically cyclorrhaphan. It has a flattened ventral surface, rounded dorsal surface, and large opercular area (the adult had eclosed). There are no features of the puparium diagnostic of particular families, such as spines or a pair of everted anterior spiracles.