The group of Opatrina genera with divided eyes and expanded protarsi are informally known as the blapstinoids. The West Indian members of this group have been historically placed in the genera Blapstinus Dejean, Cenophorus Mulsant and Rey, Ctesicles Champion, Diastolinus Mulsant and Rey, Platylus Mulsant and Rey, and Sellio Mulsant and Rey. The sole fully-winged group is Blapstinus Dejean, which ranges far beyond the geographic limits of this paper. Only those Blapstinus that are recorded from the Biogeographic West Indies are treated here. All species of the remaining genera, including extralimital species placed in Diastolinus Mulsant and Rey, are reviewed and the genera redefined. The extensive and complicated nomenclatural history of this group is fully reviewed. All genera are redefined, diagnosed and the described species reassigned. These genera now include Cenophorus, Diastolinus, Goajiria Ivie and Hart, new genus (type species: Diastolinus curtus Mulsant and Rey, 1859), Nevisia Marcuzzi, new status, Platylus, and Xerolinus Ivie and Hart, new genus (type species: Diastolinus sallei Mulsant and Rey). Sellio and Ctesicles are synonymized with Diastolinus, new synonymies. With the exception of the species of Diastolinus sensu novo, which are revised in a companion paper, each species with a literature history is listed with a full synonymical table, a distributional synopsis, and historical notes on nomenclature. Forty new island records are reported, and dozens of incorrect island records based on misidentifications are corrected. Keys to these genera and additions to the key to North American genera of tenebrionids are provided. Further major nomencltural acts include: Diastolinus impressicollis Fairmaire and Diastolinus brevicollis Fairmaire are removed from Opatrina, and the first is placed as Goniadera (Anaedus) impressicollis (Fairmaire), new combination and the later placed incertae sedis in the Stenochiini. Blapstinus decui Ardoin is returned to original combination from Diastolinus; Diastolinus domingoensis Marcuzzi is placed as Blapstinus domingoensis Marcuzzi, new combination; Diastolinus genaroi Garrido as Blapstinus genaroi (Garrido), new combination; Diastolinus hispaniolensis Marcuzzi as Blapstinus hispaniolensis (Marcuzzi), new combination; Diastolinus inflatitibia Marcuzzi as Blapstinus inflatitibia (Marcuzzi), new combination; Diastolinus klapperichi Marcuzzi as Blapstinus klapperichi (Marcuzzi), new combination; Diastolinus puertoricensis Marcuzzi as Blapstinus puertoricensis (Marcuzzi), new combination; Diastolinus fuscicornis Chevrolat, 1877 as Blapstinus punctatus (Fabricius), new combination; Sellio coarctatus Mulsant and Rey, 1859 as Diastolinus coarctatus (Mulsant and Rey), new combination; Sellio gladiator Garrido as Diastolinus gladiator (Garrido), new combination; Ctesicles insularis Champion as Diastolinus insularis (Champion), new combination; Ctesicles maritimus Champion as Diastolinus maritimus (Champion), new combination; Sellio tibidens Quensel as Diastolinus tibidens (Quensel), new combination; Diastolinus alfaroi Garrido and Gutiérrez as Xerolinus alfaroi (Garrido and Gutiérrez), new combination; Diastolinus armasi Marcuzzi,