A classic “escape and radiation” coevolutionary model of host shifts is examined in moths of the genus Depressaria Haworth 1811 that feed on plants of varied toxicity. A phylogeny is constructed using morphological data analyzed under the parsimony criterion, the first modern phylogeny of the subfamily that includes New World and Old World species. The results of this analysis suggest that Depressaria is monophyletic, as are historical species groups of Depressaria. Patterns of host-plant usage do not support an escape and radiation model but rather suggest that feeding on plants containing toxic furanocoumarins may be the ancestral conditions for Depressaria. Thus, a model of escape from control and colonization of more toxic hosts does not apply above the species level. Other phylogenetic results indicate Himmacia Clarke 1941 may be a basal lineage of Depressariinae and Semioscopis Hübner 1825 is not a member of this subfamily. In spite of some apparently very specialized larval features, we conclude that Hasenfussia Fetz 1994 is a member of Depressaria.

Thaumatomyrmex is a rarely collected ponerine genus in which the mandibles are armed with long spine-like teeth. We provide the first description of the gyne for the genus. The gyne is similar to the worker in having the same type of tooth morphology, color and pilosity, but differs in having mesosomal development associated with flight. The specimen still possesses the wing bases.

Myrmecoroides Gross is revised and a new diagnosis is provided for the genus. The two previously recognized species, M. carinatus Gross and M. grossi Carvalho, are redescribed. Three new species are described: M. cassowary, M. monteithi, and M. rufescens. The male and female genitalia are documented and illustrated where specimens of each gender were available. Phylogenetic analysis of the species is given. The common name, Hatchet Head Plant Bug, is introduced for the genus, in recognition of the greatly bicompressed head.

The phyline plant bugs belonging to the tribe Phylini in Thailand are reviewed. Sixteen species in eight genera that have hitherto been recognized are further documented. Nine species are described as new: Atractotomoidea izyaslavi, Decomia nigrissima, D. schuhi, D. taksini, Decomioides kazutakai, D. verecundus, Malaysiamiris rufobadius, Moissonia sakaerat, and Psallus buddha. Decomioides schneirlai Schuh is reported from Indochina for the first time and diagnosed. In addition, the following six new species, confirmed during examinations of related materials from the tropical and subtropical Asia, are described: Atractotomoidea insulicola (from Ryukyus, Japan), Decomia panayensis (Visayas, Philippines), Moissonia larutensis (Peninsular Malaysia), M. pardalis (Peninsular Malaysia), M. takaii (Ryukyus, Japan) and Opuna schwartzi (Peninsular Malaysia). Decomia cephalotes Poppius known only by a single male from Taiwan is recorded from the Ryukyus and diagnosed. Male and female genitalic structures are described and figured for most species. Biology and immature forms are reported in detail for Decomioides verecundus, Moissonia importunitas and M. takaii.

One new species of the Oriental planthopper genus Varma Distant (1906) (Hemiptera: Fulgoroidea: Tropiduchidae), V. serrata Men & Qin, sp. nov. (southern China: Yunnan) is described and illustrated. A checklist of known species of the genus Varma along with a key to known species are provided. The type specimens of the new species are deposited in the Entomological Museum, Northwest A & F University, Yangling, Shaanxi Province, China (NWAFU).

Weeping lovegrass (Eragrostis curvula (Schrad.) Nees; Poaceae), an African species planted in the southern United States for erosion control and forage, has been colonized by a diversity of native planthoppers. Collecting data and previously recorded host plants are provided for 26 species of Fulgoroidea in 12 genera and 5 families; nymphs of 13 fulgoroid species were observed. New state records are given for 16 planthopper species; 15 planthopper species are considered little-known or rarely collected.