Megachoriolaus Linsley, 1970

Megachoriolaus Linsley, 1970: 128; Monné, 2006: 127 (cat.).

Type species: Megachoriolaus chemsaki Linsley, 1970 (original designation).

According to Chemsak (2005), this genus has a moderately robust form; the elytra parallel–sided or slightly expanded posteriorly; antennae relatively short in both sexes, basal antennomeres shiny, usually abbreviated, clothed with coarse suberect hairs, antennomere 4 short, outer antennomeres thickened or subserrate. Pronotum with punctation not finer than that of base of elytra; prosternum with intercoxal process very narrow; mesosternum with intercoxal process prominent, not recessed between coxae. Legs with procoxae prominent; posterior tarsi distinctly shorter than tibiae, first segment usually not longer than remaining segments combined. Elytra with fine, non-elevated costal lines. Abdomen with last segment in male not excavated.

Megachoriolaus includes eight species from Mexico and Central America: M. chemsaki Linsley, 1970, M. flammatus (Linsley, 1961), M. imitatrix Linsley, 1970, M. lineaticollis Chemsak & Linsley, 1974, M. nigricollis Chemsak & Linsley, 1974, M. patricia (Bates, 1885), M. spiniferus (Linsley, 1961), M. unicolor (Bates, 1892) and M. yucatanus Giesbert & Wappes, 2000, as well as M. cruentus (Martin, 1930), M. ignitus (Schaeffer, 1908) and M. texanus (Knull, 1941) from the mountains of the southwestern United States. We propose to add three species from South America, previously in Euryptera, by the presence of Megachoriolaus generic characters as elytra parallel–sided, without dorsal carinae. These are: M. atripennis (Bates, 1870), new combination, M. bicolor (Gounelle, 1911), new combination and M. venustus (Breme, 1844), new combination . A new species is described from Brazil (Rondônia) and Bolivia.