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 (3): 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, 13 ( 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 13, 3ex. [DNA sample barcodes 10073492, 10073493, 10073495] ( ZMUN), 1♀ ( MHNG), 13 ( 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

SEM of head and pronotum. (4) Deleaster pectinatus Fauvel ; (5) D. negus sp. n.; (6, 7) D. gibbosus sp. n., N Kivu (6) and W Uganda (7). Scale bar = 0.5 mm.

(8-9) Deleaster pectinatus Fauvel , elytral apex and abdomen (8), apex of tergite VIII (9). (10) D. negus sp. n., abdominal apex. (11) D. gibbosus sp. n., abdominal apex. All in dorsal view, SEM in “Compo” mode. Scale bar = 0.25 mm for (9), 0.35 mm for (10), 0.40 mm for (11) and 1.00 mm for (8).

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.

(12-13) Deleaster pectinatus Fauvel , antenna (12) and lateral part of abdomen (13), dorsal view. (14-16) D. gibbosus sp. n. lateral part of abdomen (14), elytral apex with abdomen (15) and abdominal apex (16), dorsal views. All SEM in “3D mode”. Scale bar = 0.35 mm for (16), 0.80 mm for (15), 1.00 mm for (12-14).

(17-20) Deleaster gibbosus sp. n., male, aedeagus frontal (17) and lateral (18) views, tergites IX (19) andX (20). (21-24) D. negus sp. n., male, aedeagusinfrontal (21) andlateral (22) views, tergitesIX (23) andX (24). Scalebar = 0.34 mmfor (17-18), 0.40 mmfor (19-24).

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.