Operclipygus farctissimus, Caterino, Michael S. & Tishechkin, Alexey K., 2013

Caterino, Michael S. & Tishechkin, Alexey K., 2013, A systematic revision of Operclipygus Marseul (Coleoptera, Histeridae, Exosternini), ZooKeys 271, pp. 1-401 : 189-191

Operclipygus farctissimus sp. n. Fig. 50B

Type locality.

Not specified beyond Brazil.

Type material.

Holotype male: “Braz.” [handwritten]/ "Caterino/Tishechkin Exosternini Voucher EXO-00303" (BMNH).

Diagnostic description.

As with the preceding, this species is very similar to Operclipygus distinctus , except as follows: length: 2.03 mm, width: 1.87 mm; body piceous with elytra faintly rufopiceous; frontal stria very nearly complete, only narrowly interrupted above antennal bases; antennal bossae weakly produced; pronotal disk with strong basal plicae, extending forward about one-third pronotal length; central part of anterior pronotal margin very weakly projecting at middle; elytral striae not very strongly impressed, but striae 1-5 widened slightly to apex, outer subhumeral stria present in apical half only, inner subhumeral stria absent, striae 1-3 complete, 4th stria present in apical third, 5th stria present in apical fourth, sutural stria present in apical two-thirds; prosternal keel very broad, emarginate at base, carinal striae strongly divergent basally; mesoventrite weakly projecting, marginal stria interrupted; mesometaventral stria arched forward at middle, sinuate near mesocoxa, extending posterad toward inner third of metacoxa; propygidium with rather small, round punctures separated by about their diameters, finer ground punctures most evident toward sides and posterior margin; pygidium with fine, dense ground punctation, and few slightly coarser punctures near basal margin; marginal pygidial sulcus fine, obsolete in basal half. Male genitalia mostly similar to those of Operclipygus farctus (see Figs 48 A–D, K), except that the ventrolateral apodemes of T8 are more distant ventrally, with midlateral desclerotization not distinct (though it is still notched as seen in lateral view); S9 more strongly and somewhat asymmetrically expanded basally, indistinguishable from that of Operclipygus subrufus .

Remarks.

This species is relatively easy to distinguish in this group, with a broadly rounded, convex, faintly bicolored body(Fig. 50B), strong pronotal plicae, and very weakly projecting anterior pronotal margin. It is only known from the single type specimen, with an unfortunately imprecise type locality.

Etymology.

This species’ name refers to its relationship with Operclipygus farctus , but also to its more broadly rounded, convex ( ‘farctate’) form.