Operclipygus marginellus (LeConte, 1860) LeConte, 1860

Caterino, Michael S. & Tishechkin, Alexey K., 2013, A systematic revision of Operclipygus Marseul (Coleoptera, Histeridae, Exosternini), ZooKeys 271, pp. 1-401 : 298-301

Operclipygus marginellus (LeConte, 1860) comb. n. Figs 80A81 A–D, GMap 29

Phelister marginellus J.E. LeConte 1860: 311; Tribalister marginellus : Horn 1873: 299.

Type locality.

Not specified beyond Maryland State, USA.

Type material.

Lectotype, herein designated: “Maryland” / " Phelister marginata [sic]" / " Tribalister marginellus Horn (Lec.)" / "MCZ Type 35024" / "Aug.-Dec.2004 MCZ Image Database" / "LECTOTYPE Phelister marginellus LeC. M.S. Caterino & A.K. Tishechkin des. 2010" (MCZC). This species was described from an unspecified number of specimens, and the lectotype designation fixes primary type status on the only known original specimen.

Other material.

USA: Florida: 1: Levy Co., 4.0 mi. SW Archer, 29°30'10"N, 82°24'23"W, 19-26.iv.2000, P. Skelley, barrier pitfall trap (FSCA), 1: 13-25.vii.2000, 1: 18-21.v.1988, P. Skelley, window trap in rosemary, turkey oak sandhill (FSCA); 1: Alachua Co., 5.v.1993, R. Lundgren, flight barrier trap in hardwood hammock (CHPWK), 1: 18.vii.1994 (AKTC), 2: 18.vi.1995 (CHPWK); 1: Polk Co., Lake Marion Creek Estates, FIT, 26.x-9.xi.1999, R. Morris, FIT (AKTC). Texas: 1: Angelina Co., Angelina NF, ~3mi. NE Rockland, 31°3'19"N, 94°22'06"W, 19.ix-2.x.1996, Clarke, Menard, Riley, pitfall, unmanaged longleaf pine (TAMU). Wisconsin: 1: Sauk Co., Spring Green Preserve SNA, 43°11'58"N, 90°03'32"W, 12.vii.2003, J.P. Gruber, in nest Aphaenogaster sp., under rock on bluff prarie (CHJG), 1: 17.vi.2000, attached to leg of live Aphaenogaster treatae Forel, under board in sandy oak barren (CHJG), 1: 19-30.v.2001, J.P. Gruber, FIT, 1: 30.v-16.vi.2001, J.P. Gruber, FIT (CHJG).

Diagnostic description.

Length: 1.68-1.75 mm, width: 1.50-1.55 mm; body rufescent, broadly rounded, strongly convex, with very fine granulate microsculpture on most surfaces; frons broad, weakly depressed at middle, sides of frontal stria rounded, curving evenly, transverse across front; supraorbital stria complete, connected to sides of frontal stria; epistoma weakly depressed, slightly elevated at sides, weakly emarginate apically; labrum about 2.5 × as wide as long, flat, weakly emarginate apically; left mandible with broad, blunt basal tooth, right with slightly smaller, subacute tooth; pronotum lacking prescutellar impression, with only very faint, shallow lateral punctures; marginal pronotal stria continuous along all edges; lateral submarginal pronotal stria complete, close to margin, subcarinate, continuous with anterior submarginal stria, pronotal disk depressed along their inner edges; median pronotal gland openings faintly annulate, located about two-thirds pronotal distance behind anterior margin; elytron with two complete, crenulate epipleural striae, outer subhumeral stria carinate, forming lateral elytral margin continuous with lateral pronotal margin, inner subhumeral stria absent, dorsal striae 1-5 complete, rather broadly depressed, with outer edge of stria strongly carinate, sutural stria obsolete in basal third, similarly deeply impressed, all striae converging toward midline apically; elytral disk with numerous coarse punctures near apical margin; prosternal keel truncate at base, with carinal striae complete, divergent and free basally and apically; prosternal lobe very short, with marginal stria weak to obsolete; mesoventrite broadly and shallowly emarginate along anterior margin, with marginal stria very close to margin, weak at middle; mesometaventral stria broadly arched forward to anterior mesoventral margin, meeting inner corner of mesocoxa at side, continued by lateral metaventral stria which extends laterally, parallel to postmesocoxal stria, strongly abbreviated; metaventrite moderately convex; 1st abdominal ventrite with two lateral striae, depressed along complete inner lateral stria, outer stria obsolete basally; propygidium uniformly and densely covered with coarse punctures; pygidium with fewer and sparser punctures, mainly at sides, impunctate toward apex; marginal pygidial sulcus well impressed along most of margin, obsolete toward base. Male genitalia (Figs 81 A–D, G): accessory sclerites present; T8 short, with sides subparallel in basal two-thirds, abruptly narrowed to apex, apical emargination narrow, basal emargination nearly reaching basal membrane attachment line, ventrolateral apodemes evenly developed to base and apex, nearly meeting along midline; S8 elongate, subparallel, with apical guides well developed throughout most of length, ventral edges divergent to apex; T9 with sides subparallel in basal third, convergent to apex, apices narrow, opposing; T10 with halves fully separate; S9 broadened in basal half, weakly rounded at base, lacking apical emargination, apical flange entire; tegmen narrow, with sides rounded, widest just basad midpoint, ventromedial projection weak, ‘U’ -shaped, barely projecting beneath about one-fourth from base; median lobe about one-third tegmen length, proximal apodemes not obviously differentiated; basal piece almost one-half tegmen length.

Remarks.

The two Nearctic species of the Operclipygus marginellus group are easily distinguished. Operclipygus marginellus has distinctly carinate elytral striae (Fig. 80A), whereas those of Operclipygus striatellus are merely deeply impressed (Fig. 80B).