Limnebius lobatus, Perkins, 2017

Perkins, Philip D., 2017, Hydraenidae of Madagascar (Insecta: Coleoptera), Zootaxa 4342 (1), pp. 1-264 : 161-163

Limnebius lobatus , new species

Figs. 145 (habitus), 155 (aedeagus), 298 (map)

Type Material. Holotype (male): Toliara, Manakaravavy , Manakaravavy R. dried out river with waterpools on sandy bottom with algal mats, N:-24° 28,162, E:44° 35,683, elev. 210 m, 18 v 2006, Bergsten et al. (P48) ( NHRS) . Paratypes (16): Same data as holotype ( NHRS). Antsiranana, 13.2076S 49.0733E Diana, 5km E of Ambilobe along RN 5A, stream under the bridge, stream with sand and algae, elev. 0 m, 13° 12' S, 49° 4' E, 31 x 2014, R. Bukontaite & J.H. Randriamihaja ( MAD14-29 ) (1 NHRS); Ankarana , wide sandy river, elev. 20 m, 12° 57' S, 49° 8' E, 1 xi–30 xii 2004, M. Balke (MD 022) (5 ZSMC) ; Fianarantsoa, Sendrisoa Sendrisoa, Ambilavao , hygropetric, brownish muddish water seeping over rock = standing water with vegetation, S 22 0.585 E 46 57.024, elev. 1165 m, 22° 1' S, 46° 57' E, 7 v 2006, Bergsten et al. (P38) (1 NHRS) ; Mahajanga, Melaky: Tsingy de Bemaraha NP. S 18.75595 E 0 44.71245, elev. 80 m, 18° 45' S, 44° 43' E, 17 xii 2009, J. Bergsten, N. Jönsson, T. Ranarilalatiana, HJ. Randriamihaja ( MAD09-67 ) (2 NHRS) ; Toliara, Menabe: Kirindy RS. S 20.07655 E 0 44.67532, elev. 57 m, 20° 5' S, 44° 41' E, 12 xii 2009, J. Bergsten, N. Jönsson, T. Ranarilalatiana, HJ. Randriamihaja ( MAD09-47 ) (3 NHRS).

Differential Diagnosis. Habitus as in Fig. 145 ; a moderately large brownish species with elongate oval body form; it is the least convex of the species described herein. The dorsum of the head is dark brown, except for the lateral areas of the clypeus, which are light brown; the pronotum is darker on the disc than laterally and posteriorly. The habitus is similar to that of L. labratus , which is smaller (ca. 0.93 vs. 0.86 mm). The aedeagus is elongate and slender, with the distal ¼ slightly widened and rather blunt. Also see the differential diagnosis of L. bergsteni .

Description. Size: holotype (length/width, mm): body (length to elytral apices) 0.93/0.45; head width 0.33; pronotum 0.24/0.45; elytra 0.54/0.45; approximate height, lateral view 0.25 Dorsum with head dark brown except lateral areas of clypeus light brown, pronotum dark brown on disc, grading to light brown laterally and posteriorly, elytra brown to light brown, scutellum darker. Body form very weakly drop-shaped. Pronotum with disc shining, non-microreticulate, very sparsely finely punctulate, each puncture with very short adpressed seta; area posterior to eye (side view) with slightly larger punctures, each puncture with adpressed seta, longer than setae on disc. Elytra very weakly effacedly microreticulate, with punctures and setae similar to those on pronotum.

Males with first three pro- and mesotarsal segments slightly enlarged, with adhesive setae. Labroclypeal suture arcuate in frontal view in both sexes. Labrum simple, similar in sexes. Lateral angle of elytral apices more widely rounded and apices more truncate in males than in females, sutural angle more acute in females.

Etymology. Named in reference to the lobate shape of the aedeagal apex.

Figures

FIGURES 144 – 148. Limnebius holotypes, habitus dorsal and lateral, and frontal for L. labratus.