Oedichirus bicristatus, 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 : 44-46

Oedichirus bicristatus , new species

Figures 40 , 56–60

TYPE MATERIAL: Holotype. Male. ‘‘ Brasilien San Paulo Barbiellini/barbiellinii Bernh. Typus unic./Chicago NHMus M.Bernhauer Collection/ Holotype Oedichirus bicristatus Herman. ’’ Deposited in the Field Museum of Natural History, Chicago. (Left maxillary palpomeres 3 and 4 and right antennomeres 3–11 are missing. The head and prothorax are separated from the remainder of the body and both are glued to the card.)

TYPE LOCALITY: Brazil: São Paulo: São Paulo (23 ° 359S, 46 ° 439W). (The label reads ‘‘ San Paulo,’’ corrected here to São Paulo.)

DIAGNOSIS: This is one of six New World species with paratergite III; the others are O. batillus , O. hamatus , O. isthmus , O. optatus , and O. sinuosus . The males of O. bicristatus can be separated from the preceding five and all other New World species by two large, dense clusters of setae on sternum VIII (fig. 59). The setae of each cluster are posterolaterally directed and recumbent from the medial edge to a crest of erect setae on the lateral edge of each cluster. The two clusters are separated medially by a longitudinal, irregular row of setae. The aedeagus (fig. 57) has a lobe on the right lateral edge of the ventral sclerite and the lateral edge of the lobe is carinate. Both parameres are fused or strongly appressed to the median lobe for most of their lengths. The female is unknown.

DESCRIPTION: Length: 5.9 mm. Length of head: 0.6 mm. Width of head: 0.8 mm. Pronotal length: 1.0 mm. Pronotal width: 0.9 mm. Elytral length: 0.8 mm. Elytral width: 0.9 mm.

Body concolorous reddish brown. Legs concolorous pale reddish brown, without femorotibial spots.

Head about a third wider than long (HW/ HL: 1.3). Frontoclypeal ridge incomplete, separated medially. Dorsal surface without V-shaped depression; punctation coarse and dense medially and laterally, and less dense posteriorly. Labrum quadridentate; surface without tubercle near submedial denticle.

Pronotum about a tenth longer than wide (PL/PW: 1.1). Pronotum with coarse punctation; punctation arranged in scattered, dense clusters; surface with moderately deep, submedial, punctate groove on basal half beginning near middle. Elytra with length about a fifth less than width (EW/EL: 1.2); surface coarsely punctate and slightly convex.

Abdominal segments III to V with dense, coarse punctation; VI with dense, moderately coarse punctation, and VII with sparse, fine punctation; III to VI with even basal punctation; III to V with moderately welldeveloped transverse row of punctures near middle. Segment III with narrow paratergite about half as long as segment; tergum and sternum separated from base to posterior margin. Tergum III without median point extending from transverse basal ridge. Tergum VIII with truncate posterior margin; transverse basal ridge irregularly microsinuate, broadly, shallowly curved anteriorly, and without median point. Tergum IX with lateroapical process about a fifth longer than midbasal length (LLaP/L9 5 1.2), moderately bent ventrally, and slightly diverging from other process; ventromedial margin without posteriorly directed spur (cf. fig. 158).

MALE: Labral surface without tubercle between denticles. Sterna VI and VII unmodified. Sternum VIII (fig. 59) with shallow, symmetrical emargination of posterior margin; emargination about one eighth of length of sternum, wider than deep, with rounded basal margin, and posterior margin not membranous; surface with two dense clusters of spiniform setae on each side of midline extending anteriorly from emargination; clusters separated medially by irregular row of setae; setae of each cluster recumbent and posterolaterally directed from mesial edge and increasingly erect to crest of erect setae on lateral edge of cluster; setae of lateral crest posteriorly directed; surface with shallow, median depression proximad of setal mass and reaching to basal ridge; depression impunctate and asetate; surface with lateroposteriorly directed ridge laterad of setal cluster and attached apically with sublateral, anteriorly directed ridge; transverse basal ridge with median fifth abruptly and strongly curved anteriorly. Tergum IX with process reduced to small lobe on anterior margin of anteroventral angle. Sternum IX (fig. 60) moderately asymmetrical; anterior margin narrow and broadly rounded; posterior margin slightly truncatosinuate; right lateral margin broadly rounded and left lateral margin broadly and shallowly curved from posterior end to about basal third, then strongly round, then slightly emarginate to basal margin.

Aedeagus (figs. 56–58) asymmetrical. Ventral sclerite with short, broad lobe extending lateroventrally from apical fifth of right side; lobe with lateral edge carinate; ventral sclerite without apicoventral process extending from posterior margin. Parameres long, tapered, moderately wide basally, slender apically, fused to median lobe basally, and free of median lobe apically.

FEMALE: Unknown.

ETYMOLOGY: The name is from the Latin bi -, ‘‘two,’’ and cristatus, ‘‘crested,’’ and refers to the two tufts or clusters of seta on sternum VIII of the male.

DISTRIBUTION: Brazil, São Paulo state (fig. 40).

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. 56–60. Oedichirus bicristatus. 56. Aedeagus, right lateral. 57. Aedeagus, ventral. 58. Aedeagus, left lateral. 59. Sternum VIII, male. 60. Sternum IX, male.