Baloghianestes korupensis Ballerio, Gill & Grebennikov

Ballerio, Alberto, Gill, Bruce D. & Grebennikov, Vasily V., 2011, Illustrated overview and identification key to Cameroonian Ceratocanthinae beetles (Coleoptera: Scarabaeoidea: Hybosoridae) with description of four new species, Zootaxa 2892, pp. 1-24 : 9-11

Baloghianestes korupensis Ballerio, Gill & Grebennikov , n. sp.

( Figs. 6 , 7 B)

Material. Holotype, male: Cameroon S.-West Prov., Korup N. P., Rengo Camp, N05°02.194’ E008°49’ 769, 12– 16.V. 2006, 300m, V. Grebennikov leg. ( CNCI) [distended specimen glued on card, dissected, genitalia mounted in DMHF resin on separate card, same pin]. Paratypes: 19 specimens [4 males and 2 females dissected], same data as holotype ( ABCB, BDGC).

Description. HL: 0.68 mm; HW: 1.32 mm; PL: 1.25 mm; PW: 2.17 mm; EL: 2.17 mm; EW: 2.23 mm. Small, flightless Ceratocanthinae . Body strongly convex; uniformly dark brown with faint brown-bronze sheen; underside and tarsi reddish brown, antennae pale yellow; head, pronotum and elytra covered by a pale yellow pubescence, visible at low magnification (45x).

Head: W/L ratio = 1.94, subpentagonal. Fore margin triangular, with angle blunt and obtuse (about 150°) and sides almost rectilinear; genae slightly produced outwards, acutely pointed; genal canthus indistinct; dorsal ocular area absent; ventral ocular area transverse, narrow. Head surface irregular, slightly convex, densely covered by impressed ocellate punctation; intervals between punctures narrow and distinctly raised with respect to the surface of the ocellate punctures; each puncture bearing in the middle a simple, erect seta.

Pronotum: short and transverse (W/L ratio = 1.72); fore angles distinctly truncate, no bead visible except for around the truncature of the fore angles; sides of fore margin, sides of pronotum and base without any visible bead, but swollen and slightly raised; pronotum almost regularly convex; entire surface covered by strongly impressed, large, doubly ocellate punctures; all punctures almost adjacent to each other; punctures large and bearing a simple, erect seta in the middle; seta longer than the setae on the head; intervals between punctures narrow and distinctly raised, especially along the swollen fore and hind margins.

Scutellum: slightly longer than wide; apex sharp and acute, with distal third narrow; sides of base notched by articular process of elytron; a small apical portion of mesepisternum visible from above; surface covered by small, impressed, ocellate punctures.

Elytra: longer than wide (W/L ratio = 1.03), dorsal outline rounded; strongly convex; entire surface covered by impressed, large, simply ocellate punctures; each puncture bearing an erect, simple seta in the middle. Humeral callus absent. Pseudoepipleura with the same microsculpturing of elytra, delimited by a sharp lateral carina. Lateral carina starting from humeral area, then interrupted around middle of its length, and then resuming again around apical third of elytra, but not aligned to the humeral portion. Elytral suture raised; inferior sutural stria present; marginal area extremely small, almost completely replaced by the articular area, which bears about 5-7 visible ridges. Wings completely absent.

Antennae short, with nine antennomeres; scape securiform; pedicellum irregularly shaped, about as wide as the distal portion of scape; funicle short with antennomeres noticeably wider than long; club as long and almost as wide as funicle with three small, setose antennomeres. Clypeopleuron developed. Labrum distally gently depressed; with a wide, U-shaped emargination; proximally fringed with few (about six) long, fine setae. Mentum with ventral surface completely flat, subrectangular, emarginate in the middle of anterior edge; labial palpi (including palpiger) with four palpomeres. Mandible with pointed apical tooth, without small secondary tooth.

Procoxae subcontiguous. Profemora with surface smooth; bearing fine, flying, long setae; with a slight emargination at distal third. Protibiae broadly curved outwards, with outer lateral edge finely serrate; apical spur slender with tip acute. Protarsus attached near apical third on lateroventral surface of tibia with basal tarsomere shorter than the other four tarsomeres combined; protarsomeres 2–4 short and subequal; protarsomere 5 slightly longer bearing two small, evenly curved claws; protarsomeres, excluding protarsomere 5, with tufts of setae on ventral surface. Mesocoxae and metacoxae close to each other; mesofemora with smooth surface bearing fine, flying, long setae, with a distinct emargination at distal third of hind edge. Mesotibiae slender, proximally with a large, smooth depressed area; with two short, fine, straight apical spurs near inner apical angle. Metafemora abruptly narrowed at proximal third, with surface microreticulated; metatibiae triangularly shaped with sinuate inner edge; apex of metatibiae with two short, fine, straight apical spurs. Ventral side of mesotarsi and metatarsi (with the exception of the last tarsomere) with tufts of short setae.

Secondary sexual dimorphism: males have the inner apical spur of mesotibiae shorter than the outer spur and bent slightly inwards (this character is slightly pronounced and difficult to discern), while in females both apical spurs are straight.

Male genitalia: aedeagus with parameres short and weakly sclerotized, subrectangular, slightly asymmetrical, without dorsobasal apophysis lying along anchoring point with basal piece; basal piece slightly twisted and long, about three times as long as parameres; temones present; internal sac longer than the tegmen, armed with a sclerite ( Fig. 7 B). Genital segment with branches joining together forming a distinct manubrium slightly longer than basal triangle.

Female genitalia: vaginal palpi elongate and setose, bursa copulatrix with echinulate, subcircular, large plates.

Diagnosis. This species can be easily recognised from all other representatives of the genus Baloghianestes by the following combination of characters: a) lack of humeral tubercle, b) punctation pattern of pronotum (identical to that of B. oribatidiformis ), c) elytral punctation composed of simply ocellate punctures, similar to the elytral punctures of B. lissoubai , d) shape of the sclerite of the internal sac of aedeagus.

Etymology. From the type locality: Korup National Park, Cameroon.

Remarks. Baloghianestes korupensis and B. oribatidiformis are externally similar, sharing the same pronotal punctation and the presence of a sharp carina delimiting the pseudoepipleura, although in B. korupensis the carina is interrupted medially. Both species differ from B. lissoubai in having a carina delimiting the pseudoepipleura (in B. lissoubai the pseudoepipleura is not apparent and elytral sides are therefore regularly convex in transversal section). In B. lissoubai the pronotal punctation is identical to elytral punctation and is made of areolate/simply ocellate punctures, relatively spaced out and not adjacent to each other. The genus Baloghianestes , with the addition of the three newly described species, has a majority of its defining morphological characters correlating to the loss of flight capability. It might be plausible to assume that, as presently defined, the genus is a non-monophyletic assemblage of various wingless Philharmostes independently adapted to life in forest leaf litter.

Figures

FIGURE 6. Baloghianestes korupensis n. sp., habitus. A—distended specimen, dorsal, B – D—rolled up specimen, ventral (B), dorsal (C), lateral (D).

FIGURE 7. Male genitalia of Ceratocanthinae beetles. A— Baloghianestes oribatidiformis n. sp., Bakingili population, sclerite of internal sac, B— Baloghianestes korupensis n. sp., sclerite of internal sac; C— Baloghianestes oribatidiformis n. sp., Mt. Kupé population, sclerite of internal sac, D— Baloghianestes anceps n. sp., distal part of internal sac / median lobe, E— Baloghianestes oribatidiformis n. sp., shape of parameres, lateral, F— Baloghianestes anceps n. sp., genital segment. Scale bar: 0.2 mm.