Operclipygus formicatus, 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 : 304-305

Operclipygus formicatus sp. n. Figs 80 D–FMap 30

Type locality.

BRAZIL: Minas Gerais:Mar de Hespanha [21°52'S, 43°0.5'W].

Type material.

Holotype female: "Mar de Hespanha, Min. Ger., Brasil, A. Heyne, BerlinW."/ " Discoscelis formicata Lewis Type" [nomen nudum] / "Caterino/Tishechkin Exosternini Voucher EXO-00006" (BMNH).

Diagnostic description.

Length: 5.67 mm, width: 4.66 mm; body piceous, elongate oval, strongly convex; frons broad, sides of frontal stria divergent between eyes, angulate mediad above antennal bases, arcuate dorsad at middle; supraorbital stria fine, narrowly detached from sides of frontal stria; epistoma depressed at middle, slightly elevated at sides, truncate apically; labrum rather narrow, apically arcuate; antennal club small, barely twice as long as antennomere 8, only sparsely tomentose on dorsal and ventral bases; mandibles broad, left mandible lacking basal tooth, right mandible with small, blunt (worn?) basal tooth; pronotum with faint, punctiform prescutellar impression, disk impunctate, with only inconspicuous ground punctation; marginal pronotal stria complete along lateral and anterior edges; lateral submarginal stria complete along side, bent inward at front, narrowly detached from anterior submarginal stria which is very finely impressed, faintly recurved posterad at sides; median pronotal gland openings located behind ends of anterior submarginal stria, about one-fourth pronotal length from anterior margin; elytron with two complete epipleural striae, inner and outer subhumeral striae complete, simple, dorsal striae 1-4 complete, all extended mediad along basal margin as fine striae, 5th stria present only in apical fourth, sutural stria present in apical half; elytral disk lacking apical punctures; prosternal keel weakly emarginate at base, narrow, with carinal striae complete, weakly divergent, free basally and apically; secondary carinal striae present, parallel to basal half of carinal striae; prosternal lobe truncate apically, with complete marginal stria diverging straight posterad at sides, nearly meeting lateral prosternal striae; mesoventrite narrow, anterior margin very weakly produced, with complete marginal stria; metaventrite narrowly depressed along midline, impunctate; mesometaventral stria subangulately arched forward, extending to about one-fourth behind anterior mesoventral margin, continued by lateral metaventral stria posterolaterad to outer third of metacoxa; 1st abdominal ventrite with one complete lateral stria; all tibiae broadly expanded, prothoracic tibiae with outer edge evenly arcuate, with fine marginal teeth, meso- and metatibiae approximately triangular, with apical width equal to about three-fourths tibial length, each bearing fine marginal spines; meso- and metatarsi short, retractable into poorly developed apical tibial grooves; propygidium and pygidium with ground punctation very fine, each bearing irregularly sparse, small round punctures; marginal sulcus of pygidium fine, complete. Male: not known.

Remarks.

This species is unmistakeable in its large size (Fig. 80D) and broadly expanded tibiae (Fig. 80E). If its position within Operclipygus was not so well supported, it might easily justify its own genus. Analyses indicate that it is probably the sister group to the remaining members of the Operclipygus marginellus group. Lewis's unpublished intention to place this species in Discoscelis Schmidt, an Haeteriine genus, is based purely on some superficial similarities, primarily in gross body form and the greatly expanded legs. Perhaps the reason it was never published is that he recognized the error.

Etymology.

We honor Lewis's suggested specific name for this species, which might indicate some knowledge of its myrmecophily that is not reflected on any of the specimen's labels. Its true habits remain unknown.