Madagaster simplissima, Perkins, 2017

Perkins, Philip D., 2017, Hydraenidae of Madagascar (Insecta: Coleoptera), Zootaxa 4342 (1), pp. 1-264 : 184-187

Madagaster simplissima , new species

Figs. 176 (habitus), 178 (aedeagus), 301 (map)

Type Material. Holotype (male): Fianarantsoa, 32 km S Ambositra, in seepage over exposed granite cliff face, elev. 1400 m, 20° 43' S, 47° 16' E, 25 iii 1990, W. E. Steiner, C. Kremen, V. Razafimahatratra ( USNM). Paratype: Same data as holotype (1 USNM).

Differential Diagnosis. Differentiated from other members of Madagaster, except M. franzi , by the small size. Very similar in body size and dorsal habitus to M. franzi ( Figs. 175, 176); reliable determinations will require careful examination of the male genitalia, in temporary microslide mounts ( Figs. 177, 178). The aedeagus of M. simplissima is almost twice as long as the aedeagus of M. franzi ; the gonopore bearing tubule is shorter and only slightly curved in M. simplissima , whereas in M. franzi it is longer and sinuate; the tubule, in lateral view, emerges from the dorsal part of the apex of the main piece in M. franzi , but is more centrally located at the apex of M. simplissima . In both species the paramere setae are located on both the lateral and medial surfaces, not just at the margins.

Description. Size: holotype (length/width, mm): body (length to elytral apices) 1.61/0.68; head width 0.44; pronotum 0.36/0.59, PA 0.47, PB 0.50; elytra 1.02/0.68. Dorsum and venter dark brown to piceous, legs brown, ocelli light brown.

Clypeus and frons punctulate and, in places, microreticulate; setae very fine and sparse, recumbent Labrum bilobed, with deep V-shaped apicomedian notch, microreticulate and with sparse small setae. Labrum originating at anterior of very 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 much larger than ultimate.

Pronotum with small, moderately dense granules, each with short recumbent seta; disc with two narrowly separated midlongitudinal fovea, anterior ca. twice as long as posterior; each side with two admedian and two sublateral foveae; pronotum slightly cordiform, lateral margin rounded except emarginate near base; postocular emarginations moderately deep.

Elytral suture very weakly raised. Each elytron with four non-interrupted lines, each consisting of unilinear row of very slightly raised granules; areas between granular lines with four very irregular rows of granules. Elytral apices truncate.

Mentum and postmentum densely micropunctulate, very sparsely pubescent; Genae micropunctulate, dull, concave behind cardo, without posterior ridge. Subocular groove for antenna narrow. Posterior margin of eye not carinate.

Prosternum without midlongitudinal carina. Mesoventrite without tubercle on intercoxal process. Metaventrite densely micropunctulate and with very short and very dense vestiture (plastron?); midlongitudinal depression moderately deep ( Fig. 176). First four abdominal ventrites and anterior margin of fifth with very dense, recumbent pubescence (plastron?). Legs simple.

Etymology. Named in reference to the very simple morphology.