Operclipygus minutus, 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 : 136-139

Operclipygus minutus sp. n. Figs 35 G–H38A–DMap 13

Type locality.

BRASIL: Pará:Belém, Utinga [1°27'S, 48°26'W].

Type material.

Holotype male: "BRASIL: Pará: Belém, Utinga (IPEAN), 1°27'S, 48°26'W. Piège d’interception. v.1985" / "Caterino/Tishechkin Exosternini Voucher EXO-01776" (MNHN). Paratypes (5): BRAZIL: Pará: 1:IPEAN, Utinga, Belém, 1°27'S, 48°26'W, viii.1985, FIT (FMNH), 1: xi.1984, FIT (CHND); 2: Altamira - Marabá: km 18, 3°09'S, 52°03'W, v.1984, FIT (CHND, MSCC); 1: Barcarena, 1°30'S, 48°37'W, 13-25.vi.1991, FIT (AKTC).

Diagnostic description.

Length: 1.15-1.25 mm, width: 0.81-0.87 mm; body very small, rather elongate, parallel-sided; frons very shallowly depressed, frontal stria complete, transverse across front; supraorbital stria fine, complete, meeting sides of frontal stria; epistoma shallowly emarginate anteriorly, flat, coplanar with labrum; labrum with sides narrowed, apex weakly emarginate; left mandible with fairly prominent bifid tooth at base; right mandible with single acute tooth; pronotal disk with prescutellar impression linear, almost 2 × as long as scutellum; lateral submarginal pronotal stria absent; anterior marginal pronotal stria interrupted for width of head, but meeting corner of anterior submarginal stria, which is close to margin, recurved posterad for approximately one-third pronotal length; median pronotal gland open ings situated alongside anterior submarginal stria, about 4 puncture widths from anterior margin; elytra with outer subhumeral stria present in apical half, inner subhumeral stria absent, striae 1-4 complete, 5th stria present in apical half, sutural stria present in apical three-fourths; ground punctation of elytral disks sparse but conspicuous; prosternal keel narrowly produced at base, carinal striae close, subparallel anteriorly, slightly diverging but connected basally, united in anterior arch about one-fourth from presternal suture; mesoventral margin emarginate, marginal stria abbreviated; mesometaventral stria narrowly arched forward to near mesoventral margin, displacing marginal stria; lateral metaventral stria extending toward middle of metacoxa, not abbreviated apically; 1st abdominal ventrite with two complete lateral striae close and parallel; propygidium with ground punctation sparse, well impressed, conspicuous, with small, shallow, round punctures separated by about their diameters; pygidium with fine ground punctation very dense, with coarser punctures fairly sparsely interspersed; marginal pygidial sulcus complete, fine but well impressed. Male genitalia (Figs 38 A–D): accessory sclerites present; T8 with sides subparallel, roundly converging to apex, apical emargination shallow, but with larger, distinctly desclerotized region of roughly the same shape surrounding it, basal emargination broad, shallow, basal membrane attachment line distad emargination by about one-third its depth; S8 widest at base, sides rounded, convergent to narrow subacute apices, apical guides narrow, evenly developed throughout length, halves separate, diverging from base; T9 wider, subpar allel in middle half, narrowed to basal apodemes, with prominent angles where narrowed to apex, apices curved inward, weakly subacute; T10 with halves separate; S9 desclerotized along midline, broad, narrowest near apex, widened to broad, truncate base, lateral flanges wide, widened laterally to prominent basal and apical corners, apex with narrow median emargination, apical flanges low and separate; tegmen with sides rounded, widest at middle, narrowed to subacute apices, curved downward in apical fourth, with ventral subapical cleft, medioventral process long, with truncate apex, projecting strongly beneath about one-third from base; basal piece about one-third tegmen length; median lobe short, only about one-fourth tegmen length.

Remarks.

This species is unusual in its small and narrowly elongate body form (Fig. 35G), as well as its lack of lateral submarginal pronotal stria. It is very similar to Operclipygus impositus , but is generally slightly more convex, with slightly rounder sides. Male genitalia should be examined for unambiguous identification.

Etymology.

Even by Operclipygus hospes group standards this is a small species, and is named to reflect this fact.