Hydraena epipleurata, Perkins, 2017

Perkins, Philip D., 2017, Hydraenidae of Madagascar (Insecta: Coleoptera), Zootaxa 4342 (1), pp. 1-264 : 97-98

Hydraena epipleurata , new species

Figs. 86 (habitus), 88 (aedeagus), 269 (map)

Type Material. Holotype (male): Antsiranana, Forêt de Binara , 9.4 km 235° SW Daraina, sifted litter (leaf mold, rotten wood), montane rainforest, elev. 1100 m, 13° 15' S, 49° 36' E, 5 xii 2003, B.L.Fisher (BLF 9800) (1 CAS).

Differential Diagnosis. Differentiated from other members of the species group by the combination of very coarse and dense dorsal punctation, very broad form, and very wide elytral epipleura. The maxillary palpi are comparatively short: the ratio of mxp length/body length being ca. 0.22. The aedeagus cannot be confused with any others in the species group.

Description. Size: holotype (length/width, mm): body (length to elytral apices) 1.56/0.85; head width 0.45; pronotum 0.41/0.65, PA 0.53, PB 0.54; elytra 1.00/0.85.

Body very broad. Dorsum brown to reddish brown, head and elytra slightly darker than pronotum; elytral epipleurs lighter than venter; legs brown; maxillary palpi relatively short, last palpomere wide in basal 0.5 tapering rather sharply in distal 0.5; testaceous, distal ½ of last palpomere not darker.

Frons slightly concave near eyes, slight concave medially. Head and pronotum densely coarsely punctate; most interstices narrow walls, very finely microreticulate, dull. Mentum finely sparsely punctulate, shining; postmentum densely punctate medially. Genae raised, shining, with posterior ridge, interrupted in midline.

Pronotum arcuate laterally; anterior margin straight behind eyes, emarginate behind frons; PF1 and PF2 very shallow, almost absent; PF3 and PF4 moderately deep.

Elytra arcuate laterally; summit of posterior declivity at ca. midlength; lateral explanate margins very wide; serial punctures round, deeply impressed, usually separated by narrow walls, as large as largest pronotal punctures, some punctures random near scutellum. Intervals not raised, very finely microreticulate, dull, ca. 0.5xpd, or less. Apices in dorsal aspect broadly conjointly rounded, in posterior aspect margins not forming angle with one another.

Ratios of P2 width and plaque shape (P2/w/l/s) ca. 1/0.5/2/1. P1 as wide as P2; median carina weakly sinuate in profile. P2 l/w ca. 2/1, sides parallel, apex blunt and on same level as contiguous anteromedian carina of metaventrite. Plaques narrow, elongate, moderately widely separated, very slightly raised, located at sides of median depression. Metaventrite anteromedian carina ca. as long as plaques, not quite attaining anterior level of plaques, forking in low ridge to join plaques, together with plaques forming inverted Y-shape; strong longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity to slightly past midlength of metaventrite. AIS width at arcuate posterior margin ca. 2x P2. Protibia medial margin straight, lateral margin very weakly arcuate. Mesotibia straight, widest near midlength, medial margin with 4–5 short spines. Metatibia straight, moderately wide. Metafemur more strongly arcuate on lateral than medial margin. Abdominal apex with narrow apicomedian notch.

Etymology. Named in reference to the very wide elytral epipleura.

Figures

FIGURE 86. Hydraena epipleurata, holotype, habitus dorsal, lateral, and ventral.