Operclipygus chamelensis, 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 : 295-297

Operclipygus chamelensis sp. n. Figs 78 E–F 79B, D, F, HMap 28

Type locality.

MEXICO: Jalisco: Chamela Biological Station [19°32'N, 105°02'W].

Type material.

Holotype male: "MEXICO:Jalisco, Chamela Biol. Stn., 16-20 July 1989, Robert W. Brooks #054, ex., flight interept trap"/ "Caterino/Tishechkin Exosternini Voucher EXO-00326" / "SEMC0903664 KUNHM-ENT" (SEMC). Paratypes (18): 11: same data as type (SEMC, FMNH, MSCC, AKTC); 7: same data but 14.vii.1989 (SEMC).

Other material.

MEXICO: Nayarit: 1: 1.viii.1953, under bark large woodchips, Bark tight-fitting chips; fairly fresh, mixed palm-hardwood grove, C.H. Seevers (FMNH); Oaxaca: 1: 4.7mi south San Gabriel Mixtepec, 16.vii.1985, J. Woolley & G. Zolnerowich (TAMU); Tamaulipas: 1: nr. Gomez Farias, Rancho del Cielo, 1000m, 6.vi-7.viii.1983, FIT, cloud forest, S. & J. Peck (CMNC).

Diagnostic description.

Length: 1.75-2.06 mm, width: 1.44-1.78 mm; body rufobrunneus, elongate oval; frons weakly impressed, with fine, inconspicuous ground punctation; sides of frontal stria rounded, interrupted over antennal bases, rarely complete, central portion sinuate; supraorbital stria weak, fragmented, detached from frontal stria; labrum about twice as wide as long, weakly asymmetrically emarginate; left mandible untoothed, right with small, subacute basal tooth; pronotal disk lacking prescutellar impression, ground punctation fine, sparse, with ~16 coarse lateral punctures; marginal and submarginal pronotal striae complete across front and sides; median pronotal gland openings about two-thirds pronotal length behind anterior margin; elytron with two complete epipleural striae, inner and outer subhumeral striae absent, striae 1-4 complete, 5th stria present as short apical fragment, sutural present in posterior two-thirds; elytra with apical series of small punctures; prosternal keel weakly emarginate at base, carinal striae complete, united in narrow anterior arch; prosternal keel with marginal stria abbreviated at sides, narrowly interrupted at middle; mesoventral margin weakly projecting at middle, marginal stria broadly interrupted; mesometaventral stria broadly and strongly arched forward to mesoventral margin; lateral metaventral stria extending toward middle of metacoxa; 1st abdominal ventrite with two lateral striae, both abbreviated, inner slightly longer than outer; postmetacoxal fovea absent; propygidium and pygidium lacking microsculpture, with fine, very sparse ground punctation; propygidium with medium, ocellate punctures separated by one-third their diameters in basal half, punctures smaller and sparser toward apex; pygidium with conspicuous coarse punctures uniformly separated by about 3 × their diameters; marginal pygidial stria absent. Male genitalia (Figs 79B, D, F, H): accessory sclerites absent; T8 short, with sides weakly rounded, subparallel in basal half, convergent to apex, apical emargination narrow, shallow, basal emargination broadly rounded, deep, reaching to basal membrane attachment line, ventrolateral apodemes small, distant ventrally; S8 with sides narrowed to middle, divergent near apex, apical guides narrow throughout most of their length but widened abruptly near apex, ventral halves approximate at base, diverging slightly to apex; T9 with sides subparallel in basal half, convergent to apex, apices narrow, acute on inner corner; T10 with halves separate; S9 narrowest just distad middle, basal sides weakly rounded to narrow base, apex lacking median emargination, apical flange narrowed at middle but not interrupted; basolateral corners not prolonged proximad; tegmen narrow in basal fourth, widened to apical third, sides rounded, medioventral process very weakly sclerotized, indistinct; median lobe narrow, about one-half tegmen length, proximal apodemes differentiated at midpoint into thick and filamentous sections; basal piece about one-third tegmen length.

Remarks. This species is distinguished by its complete submarginal pronotal striae (Fig. 78E), complete elytral striae 1-4, row of apical elytral punctures, and absence of marginal pygidial stria (Fig. 78F). We assign a few specimens from other parts of Mexico to this species, although they show variation in a few characters, and should be reassessed in light of additional material.

Etymology.

This species’ name recognizes Estación de Biología Chamela, where most of the specimens of this species were collected.