Operclipygus farctus (Marseul, 1864)

Caterino, Michael S. & Tishechkin, Alexey K., 2013, A systematic revision of Operclipygus Marseul (Coleoptera, Histeridae, Exosternini), ZooKeys 271, pp. 1-401 : 172-175

Operclipygus farctus (Marseul, 1864) Figs 5A46 A–C48A–D, KMap 17

Phelister farctus Marseul, 1864: 319; Operclipygus farctus : Wenzel (1976: 258).

Type locality.

Not specified beyond Brazil.

Type materal.

Lectotype, here designated: type " Phelister farctus M., Bresil" / "LECTOTYPE Phelister farctus Marseul, 1864 M.S.Caterino & A.K.Tishechkin des. 2010" (MNHN). Paralectotype: “Bresil” / “farctus” / "G.Lewis Coll. B.M.1926-369" / "PARALECTOTYPE Phelister farctus Marseul M.S.Caterino & A.K.Tishechkin des. 2010" (BMNH). This species was described from an unspecified number of specimens, and the lectotype designation fixes primary type status on one of two known syntypes.

Other material.

ARGENTINA: Misiones: 2: 15km SE Puerto Iguazú, 27.xii-6.i.1991, FIT, mature forest, roadside, S. & J. Peck (FMNH); 1: Parque Nac. Iguazú, Cantera, 200m, 8.xii-6.i.1991, FIT, old gravel pit at forest edge, S. & J. Peck (FMNH). BRAZIL: Bahia: 5: G. Lewis (BMNH); Paraná: 1: Ibipora, Faz. Doralice, 3.xi.2006, A.A. Santos (UFPR); Rio de Janeiro: 1: Boa Sorta, J. Schmidt (ZMHB); Santa Catarina: 1: Nova Teutonia, 10.x.1955, beneath leaves, F. Plaumann (FMNH), 2: 30.xi.1955, F. Plaumann (FMNH); 1: Rio Grande, tabacco, G. Lewis (BMNH). PARAGUAY: Caazapá: 1: San Rafael Reserve, Estancia Condesa/Toro Blanco, 26°19'11"S, 55°39'57"W, 8-10.xii.2000, FIT, Z. Falin (SEMC); 2: San Rafael Reserve, Hermosa, prop. Lopez family, 26°18'29"S, 55°45'3"W, 80m, 1-3.xii.2000, FIT, Z. Falin (CMNC); 3: San Rafael Reserve, Hermosa, Sosa family, 26°19'15"S, 55°44'55"W, 3-6.xii.2000, FIT, Z. Falin (SEMC, MSCC); Concepción: 1: Estancia Cororo, 26-30.xi.1999, trap with cow entrails, C. Aguilar; Itapúa: 1: San Rafael Reserve, Yataí, prop. Hostettler family, 26°38'17"S, 55°39'56"W, 100m, 25-26.xi.2000, FIT, Z. Falin (SEMC); 4: Karonay, 17mi W. San Rafael Reserve, 26°45'53"S, 55°50'37"W, 90-110m, 18-20.x.2000, FIT, Z. Falin (SEMC, AKTC, CMNC); 1: San Pedro, Cororo, 23°28'N, 56°39'W, 180m, 27-30.x.1999, J. Jensen (CHND).

Diagnostic description.

Length: 1.62-1.87 mm, width: 1.44-1.59 mm; body rufobrunneus, broadly oval, not too strongly depressed; frons and base of epistoma rather narrowly depressed at middle; frontal stria complete, sinuate above antennal bases and attached at sides; supraorbital stria present only as median fragment, detached from frontal; labrum about twice as wide as long, with slightly asymmetrical, weak median protuberance; left mandible untoothed, right mandible with small, subacute basal tooth; pronotal disk basally depressed but lacking prescutellar impression or plicae, with very fine sparse ground punctation, and ~15 coarser punctures in rather well-defined band near sides; marginal pronotal stria generally interrupted behind head, occasionally few fragments present; lateral submarginal stria continuous with anterior submarginal; pronotal gland openings both along anterior margin, median pair behind eyes, in front of postocular angle in submarginal stria, the other midway between median opening and anterior pronotal angle; elytra with one complete epipleural stria, outer subhumeral stria present in apical half, inner subhumeral stria absent, the interval between outer subhumeral and 1st dorsal striae moderately strongly swollen, striae 1-3 complete, 4th stria present in apical half, 5th stria present in apical third, sutural stria present in apical two-thirds; prosternal keel broad, flat, truncate to very weakly emarginate at base, carinal striae complete, convergent, united in front; mesoventrite weakly projecting at middle, marginal stria complete, rarely narrowly interrupted; mesometaventral stria broadly arched forward to middle of mesoventral disk, continued at sides by lateral metaventral stria toward outer third of metacoxa; 1st abdominal ventrite with complete inner lateral stria, outer stria often present, abbreviated between inner stria and metacoxa, central portion of ventrite with few small punc tures posterolaterally; propygidium with conspicuous fine ground punctation along sides and posterior margin, with coarser round secondary punctures dense, separated by about half their diameters; pygidium with dense but rather shallow ground punctation, with small secondary punctures uniformly interspersed; marginal pygidial sulcus fine, weakly crenulate, nearly complete but usually obsolete in basal corners. Male genitalia (Figs 48 A–D, K): accessory sclerites present; T8 elongate, sides weakly convergent in basal two-thirds, bent in to apex at weakly desclerotized corner (notched at this point in lateral view), apices acute, with narrow median emargination, with deep, rather narrow basal emargination that does not reach basal membrane attachment line, ventrolateral apodemes symmetrical, not more strongly developed basally, separated beneath by about one-fifth T8 width; S8 with sides subparallel to slightly convergent, with apical guides narrow, slightly enlarged along inner edge at apex, separate, weakly divergent along midline; T9 subparallel in basal third, sides evenly convergent to narrow, opposing apices; T10 with halves separate; S9 elongate, narrowest near apex, stem weakly widened to rounded base, with broad head lacking median emargination, apical flange entire; tegmen widest just basad middle, strongly narrowed to subacute apex, apex rather abruptly bent downward in apical third, with medioventral process narrowly ‘U’ -shaped, projecting beneath about one-fourth from base; median lobe about one-third tegmen length, with filamentous portions of proximal apodemes inconspicuous; basal piece nearly half as long as tegmen.

Remarks.

This small species is fairly generalized, and exhibits a combination of mostly apparently plesiomorphic states. It can be recognized by the combination of a barely abbreviated, fine marginal pygidial sulcus (Fig. 46C), along with its complete marginal mesoventral stria (Fig. 46B), moderately large, dense punctures of the propygidium (Fig. 46C), and presence of several small punctures along the posterior margin of abdominal ventrite 1 (Fig. 46B). It lacks several distinctive characters of Operclipygus bidessois , including pronotal plicae and apical elytral punctures.