Rhantus bouvieri Regimbart , 1900

Hjalmarsson, Anna Emilia, Bukontaite, Rasa, Ranarilalatiana, Tolotra, Randriamihaja, Jacquelin Herisahala & Bergsten, Johannes, 2013, Taxonomic revision of Madagascan Rhantus (Coleoptera, Dytiscidae, Colymbetinae) with an emphasis on Manjakatompo as a conservation priority, ZooKeys 350, pp. 21-45 : 28-30

Rhantus bouvieri Regimbart, 1900 Figures 2c, 3 d–f, 4b, 5 c–d, 6 c–d, 7 c–d, h

Rhantus bouvieri Régimbart, 1900: 374

Rhantus Bouvieri Régimbart, 1899: Zimmerman (1920: 199); Guignot (1961: 754).

Rhantus bouvieri Régimbart, 1899: Nilsson (2001: 48).

Type locality.

Madagascar, Fianarantsoa.

Type material

(MNHN). Lectotype♂, here designated to fix the concept of Rhantus bouvieri and to ensure the universal and consistent interpretation of the same: "Data in NHRS-JLKB000030144", "Rhantus Bouvieri Rég. M. Régimbart det.", "Museum Paris Madagascar Fianarantsoa Grandidier 1852 –91”, "Rhantus bouvieri Régimbart, 1900 Det. J. Bergsten 2011" our lectotype label.

Paralectotypes 2♀: "Data in NHRS-JLKB000030405 and Data in NHRS-JLKB0000304283", "Museum Paris Madagascar Fianarantsoa Grandidier 1852 –91”, our paralectotype labels.

Additional material studied (NHRS, BMNH, MNHN, NMW, DEAU, see Appendix):

Matsiatra Ambony (Haute Matsiatra) region (former provinces: Fianarantsoa): 2♂ (Cat. No. BMNH-743391, 743392), Andringitra NP [Zomandao river, by bridge on road to camp Belamba], 22.1043S, 46.9207E, 1420m, 09.v.2006, Bottletrap, Leg Bergsten et al.

Vakinankaratra region (former provinces: Antananarivo): 1 ♂, 1♀ (Cat. No. NHRS-JLKB000030410, 30411), Manjakatompo [pond by], 10.x.1968, Leg. Starmühlner, 2spp. (Cat. No. NHRS-JLKB000010272), Manjakatompo [Analafandriana, 500m S fish farm by the road][grassy pond][MAD11-14], 19.3619S, 47.3150E, 1730m, 03.xi.2011, Leg. Bergsten, Ranarilalatiana, Randriamihaja, Bukontaite, 8spp. (Cat. No. NHRS-JLKB000010275), Manjakatompo [500m E Lac Froid by the road][pond and inlet stream][MAD11-16] 19.3449S, 47.3338E, 1620m, 04.xi.2011, Leg. Bergsten, Ranarilalatiana, Randriamihaja, Bukontaite, 16spp. (Cat. No. NHRS-JLKB000010276), Manjakatompo [500m E Lac Froid by the road][pond and inlet stream][MAD11-16], 19.3449S, 47.3338E, 1620m, 04.xi.2011, Leg. Bergsten, Ranarilalatiana, Randriamihaja, Bukontaite, 10spp. (Cat. No. NHRS-JLKB000010273), Manjakatompo [2km NE Amparandraindrisa][pond and stream][MAD11-18], 19.3607S, 47.3009E, 1770m, 05.xi.2011, Leg. Bergsten, Ranarilalatiana, Randriamihaja, Bukontaite, 4spp. (Cat. No. NHRS-JLKB000021024), Manjakatompo [Anosiarivo][lake near source][MJK12-13], 19.3449S, 47.3041E, 2070m, 24.i.2012, Leg. Ranarilalatiana, Randriamihaja, 7spp. (Cat. No. NHRS-JLKB000021025), Manjakatompo [Poste][lake with grass][MJK12-14], 19.3542S, 47.3081E, 1800m, 24.i.2012, Leg. Ranarilalatiana, Randriamihaja.

Madagascar (region indecisive): 3♂, 6♀ (Cat. No. NHRS-JLKB000030139, 30140, 30141, 30142, 30144, 30400, 30401, 30402, 30403), Madagascar, Leg. Catat, 2♀ (Cat. No. NHRS-JLKB000030404, 30143) Madagascar [Centre-Sud], 1901, Leg. Alluaud, 1♀ (Cat. No.: NHRS-JLKB000030138) Antananarivo [city or province, indecisive], Leg. Sikora, 1♀ (Cat. No. NHRS-JLKB000030287) Forêt Tanala [province indecisive], Leg. Alluaud

Diagnosis.

Pronotum with two elongated rectangular dark spots, narrowly (or partly) separated in middle (Figure 2c). Male protarsal claws equally long, straight in lateral view apart from at base and apex (Figure 5 c–d). Male mesotarsal claws curved in lateral view, equally thin, the anterior claw somewhat longer than the posterior (Figure 6 c–d). Penis in dorsal view evenly tapering towards apex, in lateral view with a relatively sharp angle at the base (Figure 7 c–d). Parameres with inner margin undulated (Figure 7h). 9.4-10.8 mm long.

Description.

Size: ML, 9.4-10.8 mm; MW, 5.2-5.7 mm; Lp, 1.0-1.4 mm; Wp, 3.8-4.1 mm; Le, 7.2-8.1 mm (n = 18).

Head. Testaceous with black areas inside and posterior of eyes. Interocular black pattern tapering towards the interior and narrowly separated (Figure 2c). Dense micropunctation and incomplete microreticulation.

Pronotum. Testaceous ferrugineous with two elongated rectangular black areas that are narrowly separated medially (Figure 2c). Lateral rim present, distinct. Dense micropunctation and incomplete microreticulation (Figure 3d).

Elytra. Testaceous with black irrorations, leaving paler sides and yellow sutural lines (Figure 2c). Somewhat confluent to form two small black areas subapically. Microreticulation double but somewhat indistinct. Very fine punctuation within and at edges of meshes (Figure 3 e–f).

Ventral side. Dark brown to black, abdominal segments with testaceous spots along the lateral edges. Epiplura and legs, including metafemur, testaceous (Figure 4b).

Male. Protarsal claws equally long, medially straight in lateral view (Figure 5c-d). Mesotarsal claws curved in lateral view, equally thin, the anterior claw somewhat longer than the posterior (Figure 6 c–d). Penis in dorsal view evenly tapering towards apex (Figure 7d). in lateral view not evenly curved but almost angulate at base (Figure 7c). Parameres with inner margin undulating (Figure 7h).

Remarks.

In the original description, Régimbart refers to specimens from Fianarantsoa collected by Grandidier, but the holotype is not designated. The three specimens labelled "Fianarantsoa Grandidier" at MNHN are therefore considered to be syntypes and a male with genitalia extracted is designated here as the lectotype. Lectotype and paralectotypes were labelled as such.

Habitat.

Known from a river in Andringitra and streams and grassy ponds in Manjakatompo, in both cases at altitudes between 1420 to 2070 m a.s.l.

Distribution.

Endemic to Madagascar. Precise localities only known from Manjakatompo forestry station in the Ankaratra mountains and the Andringitra mountains (Figure 8). Forêt Tanala, Fianarantsoa and Tananarive are less precise region descriptions which includes Manjakatompo (Antananarivo) and Andingitra (Fianarantsoa, Forêt Tanala).