Oedichirus dilophus, Herman, 2013

Herman, Lee H., 2013, Revision Of The New World Species Of Oedichirus (Coleoptera: Staphylinidae: Paederinae: Pinophilini: Procirrina), Bulletin of the American Museum of Natural History 2013 (375), pp. 1-137 : 66-70

Oedichirus dilophus , new species

Figures 40 , 103–111

TYPE MATERIAL: Holotype. Male. ‘‘ Bolivia: Santa Cruz, Comarapa , 32.8 km NW Yungas de Siberia , 2400 m 17 ° 499240S, 64 ° 249260W 27 JAN 1999 / R. Anderson BOL1A99 001 ; ex litter berlese/SMO164510 KUNHM-ENT/ Holotype Oedichirus dilophus Herman. ’’ Deposited in the University of Kansas Natural History Museum , Lawrence, Kansas .

PARATYPE: One Female. Bolivia: Cochabamba: Cochabamba, 72 km E. Yungas (Cochabamba - Villa Tunari Rd. ) 2800 m ; 17 ° 19210S, 65 ° 539450W 3 FEB 1999; R. Anderson BOL1A99 018; ex wet forest litter/SMO168942 KUNHM- ENT. Deposited in the University of Kansas Natural History Museum, Lawrence, Kansas .

TYPE LOCALITY: Bolivia: Santa Cruz : Comarapa, 32.8 km NW Yungas de Siberia, 2400 m 17 ° 499240S, 64 ° 249260W.

DIAGNOSIS: The males of O. dilophus can be separated from all other New World species by the pair of submedial, subapical carinae on sternum VIII and the broad, deep, symmetrical emargination of sternum VIII (fig. 106). The aedeagus (fig. 104) has short, broad parameres fused to the median lobe; the posterior margin of the ventral sclerite of the median lobe is strongly sloped near the apex and the slope has a dorsoventrally flattened, apically acute process extending from it posteriorly (figs. 103–105). Among all known New World species of the genus, O. dilophus has the least coarse cephalic and pronotal punctation. The legs are concolorous yellowish brown without a dark femorotibial spot.

The females of O. dilophus are separated from those of all other New World species by the dense mat of spiniform processes covering the vulvar plate (figs. 110–111). The anteroventral angles of tergum IX are fused medially forming a narrow strap (figs. 108, 110) and the median gonocoxal plate is absent anteriad of the vulvar plate (fig. 108).

DESCRIPTION: Length: 7.1–8.0 mm. Length of head: 0.8 mm. Width of head: 0.9–1.0 mm. Pronotal length: 1.2–1.3 mm. Pronotal width: 1.0– 1.1 mm. Elytral length: 0.9–1.0 mm. Elytral width: 1.0– 1.1 mm.

Body reddish brown to dark reddish brown. Head, pronotum, and elytra dark reddish brown to reddish brown, elytra palest; abdomen dark reddish brown to slightly paler. Legs concolorous yellowish brown, without dark femorotibial spot.

Head about a tenth to a fifth wider than long (HW/HL: 1.1–1.2). Frontoclypeal ridge absent or present and incomplete, separated medially. Dorsal surface without V-shaped depression; surface with moderately coarse punctation; punctation more or less uniformly dense medially and basally and slightly denser at postocular lateral base. Labrum quadridentate; surface without tubercle near submedial denticle.

Pronotum about a tenth longer than wide (PL/PW: 1.1). Pronotum polished with moderately dense, moderately coarse punctation; surface without distinct submedial punctate groove. Elytra with length about a tenth less than width (EW/EL: 1.1); surface coarsely punctate and flat to slightly convex.

Abdomen uniformly punctate, without subapical or apical, transverse rows of punctures; segments III to V slightly more coarsely punctate than VI to VIII. Segment III without paratergite; paratergal carina extending slightly more than half of length of segment, but poorly developed beyond spiracle. Tergum III without median point extending from transverse basal ridge. Tergum VIII with broad, shallow, median emargination of posterior margin; transverse basal ridge broadly and shallowly curved anteriorly, slightly and irregularly serrate, and without median point. Tergum IX with lateroapical process about two fifths longer than midbasal length (LLaP/L9 5 1.4); moderately bent ventrally, and approximately parallel to other process; ventromedial margin without posteriorly directed spur (cf. fig. 158).

MALE: Sterna VI and VII unmodified. Sternum VIII with deep, wide emargination of posterior margin (fig. 107); emargination symmetrical, with broadly rounded base, about one fifth of length of segment, wider than deep, and with membranous anterolateral margins; surface with carina on each side of midline proximad of emargination (fig. 106); carina with medial wall more strongly sloped than lateral wall; carina with highest point subapically and from there carina strongly sloped posteriorly and gradually sloped anteriorly; carina with moderately dense concentration of setae; surface with broad, shallow, midlongitudinal depression extending anteriorly from base of emargination to about transverse basal ridge; transverse basal ridge separated medially and with medial ends widely separated and curved posteriorly (figs. 106, 107); surface without combs of setae. Tergum IX with small, slender process on anterior margin of anteroventral angle. Sternum IX (fig. 109) slightly asymmetrical; anterior margin moderately wide and emarginate; posterior margin broadly and shallowly rounded; lateral margins broadly rounded.

Aedeagus asymmetrical (figs. 103–105). Ventral sclerite with lateral margins gradually and more or less evenly convergent from base, with rounded apical margin, without lobe on left or right side, and without apicoventral process extending from posterior margin. Ventral sclerite sharply and steeply sloped apically (figs. 103, 105); slope with ventroposterior edge asymmetrical and posterior surface with moderately wide, dorsoventrally flattened, apically acute, posteriorly directed process on left side of midsagittal plane (figs. 104); Parameres (fig. 104) short, moderately broad, apically rounded, fused to median lobe, and not reaching apex of median lobe.

FEMALE: Sternum VIII with irregularly microsinuate transverse basal ridge; posterior margin slightly emarginate. Tergum IX with anteroventral angles fused medially forming narrow strap (figs. 108, 110). Median gonocoxal plate absent anteriad of vulvar plate (figs. 108, 110); gonocoxal plate posteriad of vulvar plate tapered gradually to slightly rounded posterior margin (fig. 108). Vulvar plate anteriad of median gonocoxal plate, not embedded (fig. 108). Anterior vulvar (fig. 111) lobe narrow, transverse, and apparently poorly and incompletely separated from posterior vulvar lobe and contiguous with left lateroanterior margin of posterior vulvar lobe; surface densely covered with moderately long, apically undivided cuticular processes. Posterior vulvar (fig. 111) lobe large, convex, and densely covered with cuticular processes; cuticular processes broad basally and tapered and divided apically; processes with one to five or six apices. Vulva oriented at strong angle to longitudinal axis.

ETYMOLOGY: The name is from the Greek di -, ‘‘two,’’ and lophos, ‘‘crest,’’ and refers to the two submedial ridges on sternum VIII of the males.

DISTRIBUTION: The species is known only from central Bolivia (fig. 40).

REMARKS: This species is the first of the genus reported in Bolivia.

The female was collected at a different locality than the holotype, but is considered conspecific with the holotype because they share similar cephalic and pronotal punctation and color of the legs. It differs by having a frontoclypeal ridge which is absent in the male holotype.

Figures

Figs. 39–40. Oedichirus species. Distribution. 39. Mesoamerica and the Caribbean. 40. South America. (Species described prior to present work preceded with *. Symbols ³ or ♀ signify species known only by the sex indicated. Open circle denotes multiple collecting sites.)

Figs. 103–109. Oedichirus dilophus. 103. Aedeagus, right lateral. 104. Aedeagus, ventral. 105. Aedeagus, left lateral. 106. Sternum VIII, setae removed, male. 107. Sternum VIII, male. 108. Segment IX, ventral, female. 109. Sternum IX, male.

Figs. 110–111. Oedichirus dilophus. 110. Segment IX, vulvar plate (CLSM). 111. Segment IX, vulvar plate, enlarged (CLSM).