Bolitogyrus cheungi Brunke

Brunke, Adam J. & Solodovnikov, Alexey, 2014, A revision of the Neotropical species of Bolitogyrus Chevrolat, a geographically disjunct lineage of Staphylinini (Coleoptera, Staphylinidae), ZooKeys 423, pp. 1-113 : 48-50

Taxon classification Animalia Coleoptera Staphylinidae

Bolitogyrus cheungi Brunke sp. n. Figs 21 L–N, 24H, 27F, 31A (map)

Type locality.

Panama, Darién, Cana Biological Station.

Type material.

Holotype ♂ (SEMC): PANAMA: Darién, Cana Biological Station, Serranía de Pirre, 1250 m, 7°45'18"N, 77°41'6"W, 05 Jun 1996, J. Ashe, R. Brooks, PAN1AB96 042, ex. fungusy log, [white printed label] / SM0013883 [white barcode label] / Holotype, Bolitogyrus cheungi Brunke, sp. n. [red printed label].

Paratypes (1 ♂ 1 ♀, SEMC): same as holotype except: 1200 m, PAN1AB96 039, SM0013882, 1 ♂ (SEMC), same except: 1350 m, 7.VI.1996, PAN1AB96 102, SM0043435, 1 ♀ (SEMC).

Diagnosis.

Within the Bullatus Lineage: pronotum with three punctures in dorsal row (c.f. Fig. 7D); lateral margins of pronotum strongly converging anteriad (c.f. Fig. 7C); male sternite VII not distinctly emarginate; median lobe divided into a pair of ventrally curved lateral lobes, these lobes without teeth (Fig. 21L).

Description.

Measurements ♂ (n=2): HW/HL 1.89-2.00; PW/PL 1.58-1.69; EW/EL 1.25-1.32; ESut/PL 0.80-0.84; PW/HW 1.13-1.23; forebody length 3.8-3.9 mm.

Measurements ♀ (n=1): HW/HL 1.78; PW/PL 1.57; EW/EL 1.32; ESut/PL 0.87; PW/HW 1.04; forebody length 3.7 mm.

Similar to Bolitogyrus cornutus and differing only in the following: body without metallic reflections; dorsal abdomen reddish brown with darker brown paratergites, tergites VI–VII slightly darker; segment VIII pale, yellow but dark brown laterally; genital segment of both sexes dark, brownish; all femora with dark subapical band far from apex; frons finely and densely sculptured, less glossy than in Bolitogyrus cornutus ; base of head with posterior protuberances less pronounced, flattened, their surface with coarse, asetose and often rugose punctures; microsculpture absent dorsally except as broken lines in depressions and near punctures and well-developed fine lines on temples; pronotal disc with moderately dense, coarse, asetose punctures and micropunctures, microsculpture absent except as broken lines in depressions and near punctures; lateral areas with denser punctation; pronotal protuberance well developed and produced into a horn in males, smaller than that of Bolitogyrus cornutus , apex rounded not truncate, one male with protuberance smaller than that of holotype male but still larger than that of female paratype, female protuberance not produced into a horn but distinct; lateral margins of pronotum strongly convergent anteriad in both sexes; with three punctures in dorsal row; median lobe divided apically into two lateral lobes without subapical teeth (Fig. 21L); in lateral view, median lobe gradually narrowed to subapex of lateral lobe, lateral lobes produced ventrad and with expanded, truncate apex (Fig. 21M); paramere slightly sinuate and reaching subapex of lateral lobe; in parameral view, median lobe subparallel until division into lateral lobes, lateral lobes slightly divergent and curving inward at apex (Fig. 21L); lateral lobes in parameral view separated by a broad, rounded emargination (Fig. 21L); paramere in parameral view dilated from midlength to subapex, then sharply narrowed, the following portion gradually narrowed to acute apex (Fig. 21L); paramere with pair of broad, lateral peg setae fields following apical and subapical margins (Fig. 21N); male sternite IX more strongly asymmetrical at base than in Bolitogyrus cornutus , with shallower emargination at apex (Fig. 24H); female tergite X strongly reduced, ‘anchor-shaped’, with slender base and broadly rounded apex, without accessory sclerite but basal margin of laterotergal sclerites fused across base of tergite X (Fig. 27F); female laterotergal sclerites expanded at base, fused together at middle and entirely covering most of tergite X (Fig. 27F).

Distribution.

Figure 31A. Known only from the type locality in Darién province, Panama.

Bionomics.

Bolitogyrus cheungi has been collected from fungusy logs at an elevational range of 1200-1350 m in June.

Etymology.

The first author dedicates this species to his partner, David K.-B. Cheung. His support and understanding during this project, while away from home and family, were greatly appreciated.

Comments.

The relatively small pronotal protuberance of the male paratype compared to that of the holotype may indicate some interesting polymorphism in this trait, similar to that of Bolitogyrus cornutus (see discussion under 'Natural History’) but too few specimens are known to confirm this. Bolitogyrus cheungi is not sympatric with any other known species of Bolitogyrus but is most similar to Bolitogyrus longistellus . At present, it can only be reliably separated by the distinctively bilobed aedeagus. The lateral lobes of the aedeagus in Bolitogyrus cheungi differ in shape from those of the Divisus Group and it is uncertain whether they are homologous to those of the latter. Phylogenetic analyses using a variety of morphological character systems may resolve this in the future and ascertain whether the Divisus and Cornutus Groups are natural lineages.