Deleaster gibbosus, Cuccodoro & Makranczy, 2013

Cuccodoro, Giulio & Makranczy, György, 2013, Review of the Afrotropical species of Deleaster Erichson, 1839 (Coleoptera, Staphylinidae, Oxytelinae), Revue suisse de Zoologie 120 (4), pp. 537-547 : 541-546

Deleaster gibbosus new species

Figs 3, 6-7, 11, 14-20

HOLOTYPE (♂): DEMOCRATIC REPUBLIC OF CONGO ( ZAIRE): North Kivu, Northern face of Ruwenzori , camp de Kilindera [0°23'N, 29°55'E], 2750 m, VII-VIII.1974, [leg.] R.P.M. Lejeune, à la lampe U.V. ( MRAC).

PARATYPES (7): same data as holotype, 1♂ ( MRAC); UGANDA: Western Region, Kasese District, 8km NWW Nyakalengija, Rwenzori Mts. National Park , main trail from John Matte Hut to Nyabitaba Hut, Mubuku River , 0°21.481'N, 29°58.331'E, 2538m, 17.VIII.2008, [leg.] V.I. Gusarov (3551), river banks near bridge 1♂, 3ex. [DNA sample barcodes 10073492, 10073493, 10073495] ( ZMUN), 1♀ ( MHNG), 1♂ ( NHMW).

DESCRIPTION: Measurements (n = 5; unit = mm): HW = 1.22 (1.16-1.29); TW = 1.05 (0.99-1.09); PW = 1.17 (1.08-1.22); SW = 1.72 (1.61-1.78); AW = 1.95 (1.80- 2.10); HL = 0.82 (0.75-0.87); EL = 0.45 (0.44-0.47); TL = 0.14 (0.12-0.16); PL = 0.96 (0.91-1.00); SL = 2.14 (2.02-2.26); SC = 1.97 (1.83-2.08); FB = 4.21 (3.94-4.40); BL = 6.64 (6.20-7.11).

Similar to D. pectinatus , from which it may be distinguished as follows: habitus as in Fig. 3; scape and pedicel almost concolorous with flagellum; head as in Figs 6-7; clypeus slightly trapezoid; frontoclypeal (epistomal) suture marked as a slightly impressed transversal groove; vertex with markedly curved, broad grooves (with the remnants of the ocelli in their middle) extending anterolaterally from middle of neck margin to middle of inner eyes margin, forming together a rather U-shaped impression surrounding disc, filled with dense granulose microsculpture unlike the imbricate microsculpture filling most of the groove delineating dorsal part of neck; pronotum (Figs 6-7) with hind angles rather blunt; lateral portions of posterior pronotal margin broadly arcuate; presence of two rather strongly protruding knob-like elevations near posterior pronotal angles; presence of deep, curved pronotal subbasal impression; medial pronotal groove shallow, distinct on entire length, including in subbasal impression; pronotal disc filled with conspicuous medium/fine substrigulate microsculpture, in directionality surrounding centre, latter with scattered, fine and inconspicuous punctation; elytra with posterior portion of disc conspicuously swollen; posterior portion of sutural margin markedly below level of disc; posterior elytral margin subangulate (Fig. 15); abdomen with pubescence on laterobasal parts of tergites (Fig. 14) directed only slightly outwards; pectinate middle (comb) of apical margin of abdominal tergite VIII as in Fig. 11.

Sexual characters: Female abdominal sternite VIII sinuate subapically, broadly rounded and very finely serrate on apical margin. Male abdominal tergite IX as in Fig. 19; tergite X as in Fig. 20; sternite VIII broadly produced on apex, with membranous edge; aedeagus as in Figs 17-18.

ETYMOLOGY: The Latin name of the new species means “humped” and refers to the conspicuously swollen posterior part of the elytra.

DISTRIBUTION: The species is known only from the Ruwenzori range in the Democratic Republic of Congo ( Zaire) and Uganda.

COMMENTS: Within Afrotropical Deleaster , the presence of conspicuously swollen posterior portion of elytral disc is diagnostic for D. gibbosus . The species shares with D. negus the presence on abdominal tergite VIII of a comb with a minute mesal denticle, but the two species have very distinctive aedeagi.