Baloghianestes anceps 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 : 5-6

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

( Figs. 3 , 7 D, F)

Material. Holotype, male: Cameroon S.-West Prov., Mt. Kupé at Nyasoso, N04º49.153’ E009º42.453’, 19– 21.V.2006, 1550m., V. Grebennikov leg. ( CNCI) [distended specimen glued on card, dissected, genitalia mounted in DMHF resin on a separate card, same pin]. Paratypes: 1 male [dissected] and 1 female, same data as holotype ( ABCB, BDGC).

Description. HL: 1.13 mm; HW: 1.64 mm; PL: 1.13 mm; PW: 1.98 mm; EL: 2.83 mm; EW: 2.17 mm. Small, flightless Ceratocanthinae . Body convex; shiny, 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 = 1.45; subpentagonal, fore margin triangular, with apex 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. Surface of head slightly convex, densely punctured; vertex with a small raised smooth area in the middle and coarse, deep, simple punctures; puncture distance from each other being less than their diameter; disc covered by short, impressed, horseshoe-shaped punctures centrifugally oriented, each one having a simple puncture inside the horseshoe; fore margin with two or three transverse lines.

Pronotum: short and transverse (W/L ratio = 1.75); fore angles distinctly truncate, no bead visible apart from around the truncature of the fore angles; sides of fore margin, sides of pronotum and base without visible bead. Pronotum almost regularly convex, with slightly swollen posterior and anterior margin; entire surface of pronotum covered by strongly impressed, large, doubly ocellate punctures, with a few very small ones on disc; all punctures almost adjacent to each other; ocellum large and bearing a simple seta.

Scutellum: slightly longer than wide; apex sharp, 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 simple punctures basally becoming larger and ocellate distally.

Elytra: longer than wide (W/L ratio = 0.77), dorsal outline oval; convex; whole surface shiny; covered by impressed, horseshoe-shaped, large, elongate punctures; disc with horseshoe almost closed and opening backwards; punctures becoming simply ocellate distally and laterally. Humeral callus absent. Pseudoepipleura with same microsculpturing as elytral surface; not delimited by any lateral carina apart from a short, sharp carina near humeral area. Elytral suture not raised, smooth; sutural stria fine, limited to distal fourth; inferior sutural stria present; marginal area small, almost completely replaced by an 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 antennomeres; club antennomeres small and setose. Clypeopleuron developed. Labrum distally gently depressed, with 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 very 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 other four combined; protarsomeres 2–4 short and subequal; protarsomere 5 slightly longer bearing two small, regularly 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, their surface microreticulated and wrinkled; 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 last tarsomere) with tufts of short setae.

Secondary sexual dimorphism: males with inner apical spur of mesotibiae shorter than outer one 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 weakly sclerotized, subrectangular, slightly asymmetrical, with ventral portion membranous, without dorsobasal apophysis lying along anchoring point with basal piece; basal piece slightly twisted and long, about three times as long as parameres; internal sac ( Fig. 7 D) longer than tegmen, armed with a strongly sclerotized, asymmetrical structure lying as a median lobe. Genital segment ( Fig. 7 F) 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 recognised from other Baloghianestes Paulian, 1968 species by the following combination of characters: a) head surface lacking any raised sculpturing, b) margins of pronotum, including base, not raised or swollen and c) the distinctive punctate elytra with horseshoe-shaped punctures (at least on disc), while in all other species elytral punctation is composed of ocellate punctures.

Etymology. Anceps , Latin noun in apposition meaning “ambiguous, or “undecided”, due to the uncertainties related to its placement in the genus Baloghianestes .

Remarks. Baloghianestes anceps differs noticeably from the other three species here assigned to Baloghianestes by the general shape of the elytra and elytral microsculpture (resembling, in this respect, species of Philharmostes Kolbe, 1895 ), as well as by the lack of swellings or raised structures on elytra, pronotum and head. The apical portion of the internal sac of the aedeagus, forming a kind of median lobe, is unique within the genus as well as in the Philharmostes genus group, as defined by Ballerio (2001, 2004). The placement of this new species in the genus Baloghianestes is tentative pending a better understanding of the generic limits.

Figures

FIGURE 3. Baloghianestes anceps 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.