Madagaster barbata, Perkins, 2017

Perkins, Philip D., 2017, Hydraenidae of Madagascar (Insecta: Coleoptera), Zootaxa 4342 (1), pp. 1-264 : 191

Madagaster barbata , new species

Figs. 183 (habitus), 185 (aedeagus), 301 (map)

Type Material. Holotype (male): Fianarantsoa, Andringitra NP: Riambavy R. (female) cascade hygropetric habitat, N -22° 8.761, E:46° 53.4, wet rock surfaces next to high waterfall, elev. 1739 m, 8 v 2006, Bergsten et al. (P39) ( BMNH). Paratypes: Same data as holotype (2 BMNH).

Differential Diagnosis. Similar in habitus to M. procarina and M. bergsteni ( Figs. 179, 180, 183 ). Differentiated from both species by the larger size (ca. 2.40 mm) and, in males, by the strong ridge on the genae, the mesotibiae markedly widened and with fringe of setae on the anterior margin, and the metatibiae, which are arcuate toward the midline. The pronotal foveae are deeper than in the compared species. The very complex male genitalia of the three species share a hook-shaped process on the ventral surface of the main piece, but the parameres and processes of the distal part of the main piece differ markedly ( Figs. 181, 182, 185).

Description. Size: holotype (length/width, mm): body (length to elytral apices) 2.40/1.06; head width 0.61; pronotum 0.60/0.89, PA 0.66, PB 0.69; elytra 1.43/1.06. Dorsum and venter black, legs dark brown, ocelli light brown to testaceous.

Entire dorsum dull, with very small, closely spaced tubercles, each with a short recumbent seta. Labrum bilobed, sparsely granulate and with sparse small setae except with longer setae along anterior margin. Labrum originating at anterior of slightly overhanging margin of clypeus. Labroclypeal suture moderately deep. Short, deep sulcus in front of each ocellus. Frons with deep concavity between ocelli. Maxillary palpi ca. as along as antenna. Antenna with penultimate antennomere larger than ultimate.

Pronotum with two narrowly separated midlongitudinal fovea, anterior ca. twice as long as posterior; each side with two admedian and two sublateral foveae; posteroadmedian fovea oblique, deep; transverse fovea along base; pronotum slightly cordiform, lateral margin rounded except emarginate near base; postocular emarginations deep and wide.

Elytral suture costate in posterior. Each elytron with four non-interrupted costae; first costa (from suture) slightly curved in ca. middle ½ of length. Each costa with unilinear row of granules. Areas between costae with four irregular rows of granules. Elytral apices truncate.

Mentum and postmentum densely micropunctulate, sparsely pubescent; Genae micropunctulate, dull, concave behind cardo, with very strong, high posterior ridge, obliquely oriented on each side of midline. Subocular groove for antenna moderately deep and wide. Posterior margin of eye not carinate.

Prosternum with very low, almost absent, midlongitudinal carina in basal ½, carina stronger on intercoxal process, enlarged apically.

Mesoventrite without tubercle on intercoxal process. Metaventrite densely micropunctulate and with very short and very dense vestiture; median depression oval, moderately deep ( Fig. 183 ). First four abdominal ventrites and anterior margin of fifth with very dense, recumbent pubescence (plastron?). Last ventrite (male only) oval, flat, very slightly concave, and with sparse pubescence.

Protibia slightly widened apically. Mesotrochanter with small, sharply pointed tubercle. Mesotibia markedly widened and with fringe of setae on anterior margin. Hind legs rather elongate. Metatibia slender, slightly arcuate (away from midline), apex slightly thickened and with brush of setae. Female (2.09 mm; n=1) smaller than male. Female legs simple.

Etymology. Named in reference to the hairy mouthparts.

Figures

FIGURE 183. Madagaster barbata, holotype, frontal view, habitus dorsal, lateral, and ventral.