Type material examined:

Mexico: Veracruz, Omealca (96°45' W, 18°43' N), 1 male, April 16, 1908, leg. F. Knab (holotype, NHMW).

Additional material examined:

Mexico: Pipiapan (95°03' W, 18°27' N), carrion trap, 1 specimen, 15.2.1991, leg. Morón (KU); 4 km W Sontecompan (95°59' W, 18°30' N), 1 specimen, 10.4.1966, leg. G.E. Ball (KU); Cordoba (96°55' W, 18°53' N), 1 specimen, 12.6.1908 (AMNH); Oaxaca, Palenque (91°58'W, 17°29'N), under bark, 200 m elevation, 4 specimens, 24.4.1993, leg. R.W. Brooks (KU, UIC); Jalapa (92°48' W, 17°42' N), 9 specimens without date, leg. W. Schaus (AMNH); Veracruz (96°16 W, 19°11 N), Las Cabanas, Monte Pio Veracruz, 19.1.1980, leg. Espinoza (UNAM).

Diagnosis:

O. morio is a medium-sized species without micro-punctation, but with dense microsculpture and matte surface. In this respect, it resembles a large number of species from which it can be hardly distinguished. Certain identification can be achieved only by a genital dissection. The apical part of the aedeagus is extremely long compared to the basal part. It ends in a thick, obtuse apex that is lighter in colour in comparison to the remaining aedeagus.

Description:

Length: 9.5 mm. Colour: black; legs and antennae dark brown.

Head:: 1.4 mm long, 2.0 mm wide; eyes small; shorter than temples; anterior half distinctly narrowed to front edge; anterior edge of clypeus undulate and with pair of broad teeth; in centre smoothly prominent; punctation dense and distinct; only at base of antennae impunctate; distance between punctures on average shorter than diameter of punctures; with several supraocular granular and setiferous punctures; with several short striae behind eyes; surface with weak isodiametric microsculpture, shiny; in addition to supraocular setiferous punctures, a pair of setae on disc at anterior edge of eyes, near neck, and at posterior edge of clypeus.

AntennaeAntennae with 2 nd antennomere oval; conical 3 rd 1.5 times longer than 2 nd; antennomeres 4 and 5 slightly longer than wide; subsequent antennomeres increasing in length, but more or less quadrate.

Pronotum: 1.5 mm long, 2.1 mm wide; widest at anterior edge; anterior angles tooth-like prominent; sides in anterior half slightly narrowed, in posterior half strongly narrowed; slightly emarginate in front of posterior angles; lateral margin narrow shortly behind anterior tooth; distad widened and widest in front of posterior angles; punctation less dense than on head; distance between punctures on average as wide as or wider than diameter of punctures; a small impunctate midline with a short groove in posterior half; surface with weak netlike microsculpture, more distinct than on head and, thus, less shiny.

Elytra: 2.0 mm long, 2.0 mm wide; with coarse punctation; punctures distinctly larger than on pronotum; with weak coriaceous ground sculpture, and longitudinally striate in anterior half; surface shiny.

AedeagusAedeagus nearly triangular in shape with thick and long apical part ending in a thick obtuse apex which is lighter in colour than remaining aedeagus.