Operclipygus Marseul, 1870: 75

Caterino, Michael S. & Tishechkin, Alexey K., 2013, A systematic revision of Operclipygus Marseul (Coleoptera, Histeridae, Exosternini), ZooKeys 271, pp. 1-401 : 14

Operclipygus Marseul, 1870: 75

Phelisteroides Wenzel & Dybas, 1941: 448; synonymized by Wenzel 1976: 248; Type species: Phelisteroides fungicolus Wenzel & Dybas, 1941: 452.

Tribalister Horn 1873: 299; syn. n. Type species: Phelister marginellus J.E. LeConte, 1860: 311.

Type species:

Operclipygus sulcistrius Marseul, 1870: 75

Description.

Size range: Length 1.1-5.6 mm; width 0.8-4.5 mm; Body: ovoid to elongate, sides broadly rounded to sub- or fully parallel, convex to subdepressed; color rufescent to rufo-brunneus, glabrous, rarely piceous or metallic. Head: Frons usually weakly depressed at middle, rarely strongly depressed, flat, or weakly convex; frontal stria complete, interrupted at middle, or doubly interrupted at sides, usually outwardly arcuate, rarely recurved at middle; supraorbital stria generally present across top of frons, arcuate, connected to upper ends of frontal stria or ending free, rarely absent; epistoma flat to subdepressed, very rarely convex, lacking striae along anterior or lateral margins, apex truncate to weakly emarginate; labrum 1.5 –3× as wide as long, flat to weakly convex, apical margin generally weakly emarginate, often slightly asymmetrical with weak tooth projecting ventrad, rarely outwardly arcuate; mandibles short, weakly dentate, with tooth more often on right mandible than left, rarely with both mandibles strongly toothed; antennal scape elongate, slightly expanded to apex; antennal club shape elongate oval, rarely circular, with three annuli, the basalmost two frequently interrupted. Pronotum: Pronotal sides generally narrowed to front, anterior margin behind head straight to weakly, very rarely strongly produced; disk with prescutellar impression small or lacking, never as large or larger than scutellum; disk with marginal and anterior gland openings, the innermost pair of which is frequently displaced posteriorly onto pronotal disk; marginal stria usually present along lateral and anterior margins, often interrupted behind eyes, anterior portion rarely absent; lateral submarginal pronotal stria usually present along all or most of pronotal side, simple or rarely subcarinate, rarely abbreviated from posterior end, disconnected or continuous with anterior submarginal stria; anterior submarginal stria usually present in addition to anterior portion of marginal stria; lateral ends of anterior submarginal stria, if free, frequently recurved posterad, sometimes over considerable portion of pronotal length; pronotal disk variously punctate, usually only at sides, rarely with oblique basal plicae. Elytra: one to three epipleural striae present, usually fine and close together; dorsal striae comprising 8 regular striae, highly variable in presence, completeness and degree of impression; elytral disk rarely with apical punctures, which may be diffuse or form a regular series. Prosternum: Prosternal lobe weakly deflexed, usually rounded, rarely subtruncate apically or strongly shortened, usually with marginal stria present, variably abbreviated at sides; prosternal keel projecting, truncate, or emarginate at base, with two carinal striae usually present, complete, and connected anteriorly by narrow arch. Mesoventrite: Anterior mesoventral margin varied in shape in correlation with prosternal keel; marginal mesoventral stria usually complete, rarely interrupted or absent; mesometaventral stria rarely present along mesometaventral suture, more often displaced anterad, often nearly to anterior mesoventral margin, may be angulate or arcuate, generally continuous at sides with lateral metaventral stria. Metaventrite: Disk flat to weakly convex, generally glabrous, impunctate, rarely depressed and/or setose in males, or punctate in both sexes; postmesocoxal stria present, curving close to rear of mesocoxa toward mesepimeron; lateral metaventral stria oblique, extending from inner corner of mesocoxa toward metacoxa, rarely curving toward metepisternum or continued at side by recurrent stria. Abdomen: Abdominal ventrite 1 with one or two lateral striae along inner edge of metacoxa, the outermost rarely curving laterad behind coxa; gland openings behind metacoxa usually small, inconspicuous, rarely developed into deep foveae; propygidium usually wide, short, with pair of gland openings in anterolateral corners, disk with highly varied punctation; pygidium subtriangular, variably punctate, usually with distinct marginal stria, this occasionally developed into deep sulcus, rarely with large foveae in basolateral corners. Legs: protibial margin generally without strong marginal teeth, with 4-8 weak marginal teeth, each bearing a small spine; submarginal row of spines frequently present, along with one to three longitudinal striae on posterior face, two protibial spurs present, the inner one often weak; protarsal setae often sexually dimorphic, simple in females, broadly expanded in males; protarsal claws usually simple, rarely modifed; meso- and metatibiae lacking marginal teeth, with simple series of generally fine spines; meso- and metatarsi generally with two rows of ventral spines, rarely with spines not organized in rows. Male: Accessory sclerites present or absent; 8th tergite parallel-sided to weakly tapered, with conspicuous basal and apical emarginations, ventrolateral apodemes simple, not meeting along ventral midline; 8th sternite usually divided along midline, rarely fused along part of its length, with sides upturned to form weak to moderately strong apical guides, apices usually bearing few fine setae, rarely with numerous conspicuous setae; 9th tergite divided along midline, very rarely fused near base, apices usually simple, converging but separate, ventrolateral apodemes forming moderately to strongly hooked lateral structures; spiculum gastrale (S9) generally elongate, stem weakly expanded at base, head with apical flanges, apicolateral flanges rarely well developed; 10th tergite elongate, usually divided along midline, rarely fused; aedeagus elongate, narrow, tubular, varied in shape, with apical division rather short, apices rarely convergent, usually with moderately strong ventromedial projection, easily visible from above, and often projecting beneath; median lobe usually simple, with small gonopore, elongate proximal apodemes, proximal apodemes rarely strongly dif ferentiated into proximal and distal portions; basal piece usually one-fourth to one-third tegmen length, laterally articulated with tegmen. Female: 8th tergite forming a single plate, apically emarginate; 8th sternite entire or divided along midline with basal baculi detached, articulated with sternites, basally convergent; 9th sternite present, elongate; valviferae paddle-shaped; coxites elongate, apically bi- to tridentate, with distinct, articulated apical stylus; bursa copulatrx completely membraneous; generally with single weakly sclerotized spermatheca, although multiple spermathecae have been observed, inserted beneath apex of bursa copulatrix; spermathecal shape simple, saclike, or frequently forming complex spiral; spermathecal gland present, inserted at base of spermatheca.