Pyxister devorator, Caterino, Michael S. & Tishechkin, Alexey K., 2014

Caterino, Michael S. & Tishechkin, Alexey K., 2014, New genera and species of Neotropical Exosternini (Coleoptera, Histeridae), ZooKeys 381, pp. 11-78 : 27-29

Pyxister devorator sp. n. Figs 8, 9A, 10, Map 2

Type locality.

BRAZIL: Rio de Janeiro, 17km E Nova Friburgo [22.3844°S, 42.5583°W]

Type material.

Holotype male: "BRASIL:RIO DE JANEIRO, 17km E Nova Friburgo, 22°23'04"S, 42°33'30"W, 750m, 29.I.2000, F. Génier & S. Ide, secondary mountain Atlantic for. ex. f.i.t., day 4-9, FG2000-58" / "Caterino/Tishechkin Exosternini Voucher EXO-00159" (CMNC). Paratypes (4): 1: same data as type; 3: same locality as type, but 21.i.2000, FG2000-09 (CMNC, MSCC).

Diagnostic description.

Length: 2.5-2.8 mm, width: 1.6-1.8 mm; as for generic description, with the following specific characters: frontal disk depressed at middle, with fine ground punctation especially at sides, with very few larger secondary punctures intermingled; frontal stria complete, slightly sinuate anteriorly; frontoclypeal suture indicated by fine, complete impressed line; epistoma broad, more or less flat, apical margin straight; labrum about twice as wide as long, slightly narrowed to weakly rounded apex, basally flat, but increasingly broadly depressed toward apex; pronotal sides weakly outwardly rounded, anterior emargination very faintly produced at middle, with marginal stria complete along lateral and anterior margins, submarginal stria complete along side, curving inward at front, coarsely crenulate throughout; pronotal disk with secondary punctures almost throughout, absent only mediobasally, separated by approximately their diameters; elytral epipleuron with single, complete epipleural stria rather distant from lateral margin, outer subhumeral stria more or less complete but interrupted near middle and slightly abbreviated at base, inner subhumeral stria absent, 1st dorsal stria obsolete in apical third, 2 nd– 4th striae complete, 5th stria obsolete in basal half, sutural stria complete, rather deeply impressed along suture; marginal mesoventral stria complete or nearly so, though weak medially and crowded by mesometaventral stria; meso- and metatibiae widened to apex, apical width about 3 × basal width, both strongly spinose; propygidium with fine ground punctation interspersed with secondary punctures irregularly separated by 1 –1.5× their diameters; pygidium with secondary punctures generally smaller and sparser, tending to be concentrated and more deeply impressed along lateral margins.

Remarks.

The two species of Pyxister appear clearly related, but at the same time show some remarkable differences, particularly in the structure of the head. The convex frons and strongly swollen labrum of Pyxister labralis (Fig. 9D) are not at all indicated in Pyxister devorator , which has a more or less flat frons, and a labrum which is slightly depressed and emarginate apically (Fig. 9C). Other distinguishing characters of Pyxister devorator are its complete lateral submarginal pronotal stria, apically abbreviated 1st dorsal elytral stria, and its sparsely punctate pygidia (Fig. 9E).

Etymology.

The name of this species means ‘devourer’, alluding to its strong mandibles.