Praocis Eschscholtz, 1829

Flores, Gustavo E. & Pizarro-Araya, Jaime, 2012, Systematic revision of the South American genus Praocis Eschscholtz, 1829 (Coleoptera: Tenebrionidae). Part 1: Introduction and subgenus Praocis s. str., Zootaxa 3336, pp. 1-35 : 4

Genus Praocis Eschscholtz, 1829

Praocis Eschscholtz, 1829: 6 ; Lacordaire, 1830: 284; Guérin-Méneville, 1834: 8; Dejean, 1834: 180 (cat.); Dejean, 1836: 200 (cat.); Guérin-Méneville, 1838: 92; Laporte, 1840: 186; Solier, 1840: 214 (rev.); Solier, 1851: 185 (rev.); Lacordaire, 1859: 212; Gemminger & Harold, 1870: 1904 (cat.); Burmeister, 1875: 495 (rev.); Philippi, 1887: 731 (cat.); Champion, 1895: 93 (cat.); Kolbe, 1907: 86 (cat.); Gebien, 1910: 260 (cat.); Bruch, 1915: 275 (cat.); Gebien, 1938: 398 (cat.); Blackwelder, 1945: 522 (cat.); Kulzer, 1958: 11 (rev.); Peña, 1966: 428 (cat.); Vidal & Guerrero, 2007: 73, 206; Flores, 2007: 411, 416; Flores, 2009: 23. Type species: Praocis rufipes Eschscholtz, 1829 (subsequent designation by Guérin-Méneville, 1834: 8 –9).

Redescription. Length 5.0–18.0 mm. Head. Prognathous; labrum with anterior margin not broadened; clypeus and frons with round punctures; mentum subtrapezoidal, with setae; maxillary palps with last segment axe-shaped; eyes oval; antennomere 3 shorter than 4 + 5 combined.

Thorax. Prothorax semi-mobile; pronotum with round punctures; anterior angles rounded, anterior margin concave, width of posterior margin exceeding width of anterior margin, single lateral margin slender, expanded, remote from disc, posterior margin convex, not exceeding width of base of elytra, joined in central half to elytra, posterior angles not overlapping elytral humeri; disc of pronotum convex, higher than lateral margins; mesosternum inclined forward, separated from prosternum; scutellum visible.

Elytron with punctate surface, very variable among the subgenera and species in features such as with or without carinae, lateral margin well defined with a fine edge or carina shaped or rounded not defined, single or double; epipleuron with edge, anterior margin reaching elytral humeri and posterior angle of pronotum.

Legs. Procoxal separation equal to 1/3 procoxal width; mesocoxal and metacoxal separations not exceeding mesocoxal and metacoxal width; metacoxal cavity closed laterally by metasternum and sternum 3. Ventral femoral surface with setae arising from punctures.

Discussion. The genus Praocis was described by Eschscholtz (1829) and characterized by Solier (1840, 1851) and Lacordaire (1859), who defined it as having maxillary palps with last segment axe-shaped and pronotum with lateral margin slender, expanded, remote from disc. Kulzer (1958) did not redefine the genus but pointed out the great variation in many features among the species; in his key, he characterized Praocis only as having maxillary palps with last segment axe-shaped and pronotum with anterior angles rounded. Kulzer (1958) classified the species of Praocis into 10 subgenera, six of which were new.

Examination of species of all subgenera of Praocis (sensu Kulzer 1958) allows us to define the genus Praocis on the basis of five consistent character states, some of them used in previous revisions ( Eschscholtz 1829; Solier 1840, 1851; Lacordaire 1859; Kulzer 1958): maxillary palps with last segment axe-shaped (defined here as apex twice as wide as base), antennomere 3 shorter than 4 + 5 combined, pronotum with single lateral margin slender, expanded, remote from disc, and anterior angles rounded.

Subgenus excluded from Praocis . The subgenus (Parapraocis) Kulzer 1958 is excluded here from Praocis because its species exhibit the following character states: maxillary palps with last segment subcylindric, apex wider than base (apex 1.5 times as wide as base), antennomere 3 longer than 4 + 5 combined, pronotum with lateral margin not expanded, contiguous with disc, lateral margin double, and anterior angles acute.

Examination of the external morphology of species from all the remaining genera of Praociini revealed that the character states antennomere 3 longer than 4 + 5 combined and pronotum with lateral margin double are unique to species assigned to Parapraocis and these deserve recognition as a separate genus within Praociini. Parapraocis includes three species inhabiting Peru: Parapraocis vagecostata (Fairmaire) n. comb. (type species, present designation), P. rossi (Kulzer) n. comb., and P. fumaria (Kulzer) n. comb.