Hydraena (Hydraenopsis)

Perkins, Philip D., 2017, Hydraenidae of Madagascar (Insecta: Coleoptera), Zootaxa 4342 (1), pp. 1-264 : 125-127

Hydraena (Hydraenopsis) incertae sedis

Hydraena regimbarti Zaitzev

Figs. 115 (habitus), 117 (aedeagus), 282 (map)

Hydraena marginicollis Régimbart 1903: 51 (nec H. marginicollis Kiesenwetter, 1849 ). Hydraena regimbarti Zaitzev (nomen novum), 1908 (catal.).

Type Material. Lectotype (female): "Ft Dauphin Mad. (Alluaudi); MUSEUM PARIS COLL MAURICE REGIMBART 1908; TYPE [red]; marginicollis Reg. type; [female symbol]; A. d'Orchymont vid. Hydraena (s. str.) marginicollis Reg. [female symbol]; LECTOTYPE Hydraena marginicollis Régimbart 1903 , design. P. D. Perkins 2015 [red]"; (MNHN).

Specimens examined (87): Fianarantsoa, Atsimo Antsinanana: R.S. Manombo : Parcelle I, Rearatra, Piste 56: S 23.006183 E 47.7338833, GB nets and sieves, forest stream with pools, elev. 21 m, 23° 0' S, 47° 44' E, 14 xii 2013, J.H.Randriamihaja & T.Ranarilalatiana ( MAD13-73 ) (1 NHRS) ; Ranohira (Fianarantsoa), right affl. of Riv. Ihazofotsy near ' Isalo Ranch' , 750 m asl., elev. 750 m, 22° 26' S, 45° 21' E, 25 ix 2001, Gerecke & Goldschmidt (Md 95) (1 NMW) ; Mahajanga, Boeny: Ankarafantsika NP. S 16.31215 E 0 46.81523, 76 m. a.o. 29 XI 2009 Field # MAD09-02 , 16° 18' S, 46° 48' E, J. Bergsten, N. Jönsson, T.Ranarilalatiana, HJ. Randriamihaja ( MAD09-02 ) (7 NHRS) ; Boeny: Mahavavy Kinkony RS. S 16.01334 E 0 46.00376, elev. 24 m, 16° 1' S, 46° 0' E, 6 xii 2009, J. Bergsten, N. Jönsson, T. Ranarilalatiana, HJ. Randriamihaja ( MAD09-33 ) (4 NHRS) ; Boeny: Mahavavy Kinkony RS. S 16.13337 E 0 45.95778, elev. 19 m, 16° 8' S, 45° 57' E, 4 xii 2009, J. Bergsten, N. Jönsson, T. Ranarilalatiana, HJ. Randriamihaja ( MAD09-25 ) (10 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 ) (2 NHRS) ; Boeny: Mahavavy Kinkony RS. S 16.15890 E 0 45.93967, 11 m. a.o., 16° 10' S, 45° 56' E, 3 xii 2009, J. Bergsten, N. Jönsson, T. Ranarilalatiana, HJ. Randriamihaja ( MAD09-21 ) (5 NHRS) ; Forêt de Tsimembo, 11.0 km 346° NNW Soatana , sifted litter (leaf mold, rotten wood) in tropical dry forest, elev. 50 m, 18° 59' S, 44° 26' E, 21– 25 xi 2001, Fisher, Griswold et al. (BLF 4508) (12 CAS) ; Boeny: Mahavavy Kinkony RS. S 16.14147 E 0 45.93661, water collecting hole, Field # MAD09-20.5 (next to Field # MAD09-20 ), elev. 12 m, 16° 8' S, 45° 56' E, 3 xii 2009, J. Bergsten, N. Jönsson, T. Ranarilalatiana, HJ. Randriamihaja ( MAD09-20.5 ) (1 NHRS) ; Boeny: Mahavavy Kinkony RS. S 16.01334 E 0 46.00376, elev. 24 m, 16° 1' S, 46° 0' E, 6 xii 2009, J. Bergsten, N. Jönsson, T. Ranarilalatiana, HJ. Randriamihaja ( MAD09-33 ) (5 NHRS) ; Melaky: Tsingy de Bemaraha NP. S 18.75804 E 0 44.71290, elev. 90 m, 18° 45' S, 44° 43' E, 17 xii 2009, J. Bergsten, N. Jönsson, T. Ranarilalatiana, HJ. Randriamihaja ( MAD09-64 ) (2 NHRS) ; Parc National de Namoroka, 16.9 km 317° NW Vilanandro , sifted litter (leaf mold, rotten wood), tropical dry forest, elev. 100 m, 16° 24' S, 45° 18' E, 12–16 xi 2002, Fisher, Griswold et al. (BLF 6582) (1 CAS) ; Parc National Tsingy de Bemaraha, 3.4 km 93° E Bekopaka, Tombeau Vazimba , sifted litter, tropical dry forest, elev. 50 m, 19° 8' S, 44° 49' E, 6–10 xi 2001, Fisher, Griswold et al. (BLF 4232) (4 CAS) ; Sofia: Ambinanitelo, river Ambinanitelo next to road RN6 forest stream, S 15.23948 E 47.81591, GB nets and sieves; dried up river with side pools, elev. 43 m, 15° 14' S, 47° 49' E, 18 xi 2012, J. Bergsten, R. Bukontaite, J.H. Randriamihaja & T. Ranarilalatiana ( MAD12-08 ) (6 NHRS) ; Sofia: Maropapango: river Maropapango next to road RN6, S 14.35419 E 48.01984; nets, sieves, aspirator: river with side pools, elev. 13 m, 14° 21' S, 48° 1' E, 18 xi 2012, J. Bergsten, R. Bukontaite, J.H. Randriamihaja & T. Ranarilalatiana ( MAD12-10 ) (26 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 (1 USNM) ; Betroka Reg., 1 st bridge on RN13 S of Intsoka , elev. 923 m, 23° 5' S, 46° 4' E, 7 i 2010, M. Ferroux & P. Obrdik (1 MMBC) ; Betroka (Tulear), right affl. of Riv. Mangoky NE of the villageponds near aquaeduct, elev. 830 m, 23° 16' S, 46° 0' E, 25 viii 2001, Gerecke & Goldschmidt (MD 47) (1 NMW) ; Menabe: Kirindy RS. S 20.07476 E 0 44.67075, elev. 49 m, 20° 4' S, 44° 40' E, 12 xii 2009, J. Bergsten, N. Jönsson, T. Ranarilalatiana, HJ. Randriamihaja ( MAD09-45 ) (1 NHRS) .

Differential Diagnosis. Similar in size and plaques to H sinuatipes (ca. 1.41 mm); differing therefrom in the shape of the pronotum (posterior width less), the pronotum more coarsely punctate, the pronotum maculate instead of fasciate and, in males, the metatibiae being straight, without sinuate margins. The aedeagi of the two species differ markedly ( Figs. 113, 117 ). Also refer to the remarks section.

Description. Size: Lectotype (female) (length/width, mm): body (length to elytral apices) 1.41/0.61; head width 0.37; pronotum 0.34/0.49, PA 0.39, PB 0.44; elytra 0.89/0.61.

Dorsum of head with frons and clypeus dark brown to piceous; pronotum with dark brown macula, diffusely margined, borders light brown to testaceous; elytra brown; legs light brown; maxillary palpi testaceous, distal 0.5 of last palpomere slightly darker.

Frons punctures ca. 1–1.5xef, larger and denser near eyes than medially, interstices shining, 0.5–1xpd laterally, 2–5xpd medially. Clypeus very finely sparsely punctate, interstices shining medially, microreticulate laterally. Mentum very sparsely very finely punctulate, shining. Postmentum punctulate in median depression. Genae raised, shining, without posterior ridge. Pronotum with lateral margins slightly sinuate, posterior angles nearly right angles; anterior margin straight behind eyes, emarginate in middle; punctures on disc larger and deeper than those of frons, interstices weakly shining, 1–4xpd, punctures larger and denser at anterior and posterior; PF1 absent; PF2 shallow, oval; PF3 deep and large; PF4 shallow.

Elytra weakly arcuate laterally; summit of posterior declivity at or slightly before midlength; lateral explanate margins narrow; serial punctures on disc ca. 1xpd largest pronotal punctures. Intervals not raised, shining, ca. 1xpd, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins forming (male) shallow, (female) very shallow angle, if any, with one another.

Ratios of P2 width and plaque shape (P2/w/l/s) ca. 1/0.25/1/2. P1 laminate; median carina sinuate in profile. P2 l/w ca. 2/1, sides slightly converging toward blunt apex, apex raised slightly above metaventral intercoxal process.

Plaques very narrow lines, converging slightly anteriorly, widely separated, weakly raised, located at sides of shallow median depression. Metaventrite with very short longitudinal ridge on each side, extended posteriorly from margin of each mesocoxal cavity. AIS width at slightly arcuate posterior margin ca. 1.5x P2. Protibia (both sexes) very slightly arcuate, other tibiae straight, slender. Abdominal apex (male) with apicomedian asymmetrical notch.

Remarks. The lectotype (female) was collected at Fort Dauphin. Two Hydraena species from that locality are present in the material studied, but both of these differ from the lectotype in several characters: H. furcula is much larger (ca. 2.17 vs. 1.41 mm) and the habitus and plaques differ markedly from those of H. regimbarti ; H. elementaria is closer in size (ca. 1.51 mm), and the plaques are more similar to those of H. regimbarti , however the shape, foveae, and finely punctate pronotum differ from those of the lectotype. The specimens of H. regimbarti available include several localities in Toliara ( Fig. 282), but none at Fort Dauphin.

Figures

FIGURES 117 – 118. Aedeagi of Hydraena regimbarti, non-type, and Hydraena andranomena, holotype.