Ochthebius alluaudi Regimbart

Perkins, Philip D., 2017, Hydraenidae of Madagascar (Insecta: Coleoptera), Zootaxa 4342 (1), pp. 1-264 : 223-224

Ochthebius alluaudi Regimbart

Figs. 214 (habitus), 209 (aedeagus), 306 (map)

Ochthebius alluaudi Régimbart 1903: 50 .

Type Material. Lectotype (male): "Andrahomana Mad. Sud; alluaudi Reg. ; MUSEUM PARIS COLL MAURICE REGIMBART 1908; LECTOTYPE Ochthebius alluaudi Régimbart 1903 , design. P. D. Perkins 2015 [red]" (MNHN).

Specimens examined (262): Mahajanga, Boeny: Mahavavy Kinkony RS. S 16.14147 E 0 45.93661, elev. 12 m, 16° 8' S, 45° 56' E, 3 xii 2009, J. Bergsten, N. Jönsson, T. Ranarilalatiana, HJ. Randriamihaja ( MAD09-20 ) (1 NHRS) ; Boeny: Mahavavy Kinkony RS. S 16.14653 E 0 45.94926, elev. 9 m, 16° 9' S, 45° 57' E, 4 xii 2009, J. Bergsten, N. Jönsson, T. Ranarilalatiana, HJ. Randriamihaja ( MAD09-24 ) (4 NHRS) ; Toliara, Andranomena , at black light, dry forest near open marsh, 19° 53' S, 45° 4' E, 30 iii 1990, W. E. Steiner, C. Kremen, V. Razafimahatratra (256 USNM) ; Menabe: Andranolava village, lake by the road to Kirindy Mite NP, S 20.35873 E44.4006, lake in the open area with some baobab trees, elev. 20 m, 21 xi 2013, T. Ranarilalatiana, J. Randriamihaja ( MAD13-08 ) (1 NHRS) .

Differential Diagnosis. Based on the general color pattern, especially the elytra with brownish lines through the serial punctures, and the shape of the pronotum, this species appears to be related to the south African species O. salinarius Balfour-Browne (see Perkins & Balfour-Browne, 1994). In general, O. alluaudi is a more finely sparsely punctate species, especially the strongly shining pronotal disc, and the pronotal foveae, especially the median sulcus, are shallower. The shape of the distal process of the aedeagus differs in the two species, and the male of O. alluaudi has a more prominent labral process.

Description. Size: Lectotype (length/width, mm): body (length to elytral apices) 1.65/0.78; head width 0.45; pronotum 0.39/0.57; elytra 1.04/0.78. Head and disc of pronotum infuscate or blackish, slightly metallic, lateral areas of pronotum light brown to testaceous, elytra testaceous with brownish longitudinal lines through series 1–7, maxillary palpi and legs testaceous, venter dark brown to piceous.

Eyes in dorsal aspect with 8–9 convex facets in longest series. Interocular foveae large and deep, each 1x distance separating them. Ocelli distinct, shining. Frons finely sparsely punctulate, interstices shining except duller in microreticulate area medially on disc and at sides of interocular fovea. Clypeus microreticulate. and dull laterally and basally, remaining subtriangular median area effacedly microreticulate, weakly shining. Frons and clypeus punctures each with fine short recumbent seta. Labrum in male slightly produced and reflexed over median 0.33, anterior edge of produced part straight or very weakly arcuate; in female anterior weakly emarginate. Mandible outer margin bearing, in male stout rather long spiniform setae; in female tapering curving setae.

Pronotum widest near anterior 0.25, sides regularly attenuate to base. Anterior margin on each side straight or with minute postocular process and extremely shallow postocular emargination; hyaline border well developed. Lateral hyaline narrow, sides almost straight, narrowing anteriorly ended just behind anterior angles, posteriorly continuing narrowly but distinctly round posterior angles and along base. Disc with very shallow and narrow midlongitudinal sulcus, shallower, almost obsolete in some specimens, in midlength; anterior and posterior admedian foveae shallow, weakly microreticulate, posterior sometimes extremely shallowly joined to sulcus, posterior larger than anterior; reliefs strongly shining, extremely finely very sparsely punctulate. Lateral depression and lateral fossula slightly more coarsely punctate than discal reliefs.

Elytra elongate oval, broadest about middle. Explanate margin narrow. Apices in male narrowly separately rounded, in female conjointly rather sharply rounded. Ten distinct series of punctures, series not striate-impressed except sutural in distal 0.5, punctures and interstices ca. 1–2 xef of disc, becoming finer and more separated laterally and apically. Intervals flat, 2–3xpd, slightly shining, very effacedly alutaceous.

Metaventrite with large median shining glabrous area. Abdominal ventrites 1–5 entirely clothed with dense hydrofuge pubescence. Sixth ventrite apical 0.5 in male sparsely, in female densely setose. Seventh ventrite in male apically setose on each side of median emargination, in female setose over median 0.5 of arcuate margin. Apical tergum sharply rounded, in male bearing tapering curving setae, in female bearing short stout spines and finer tapering setae. Male protarsomeres 1–2 with pad of suction setae. Sexes similar in size: males ca. 1.61–1.79 mm; females 1.49–1.88 mm.

Distribution. Currently known from four localities in western and one locality in northern Madagascar ( Fig. 306 ).

Figures

FIGURES 303 – 306. Geographical distributions of Protozantaena species, Sicilicula species, Aulacochthebius species, and Ochthebius alluaudi.