Madaglymbus semifactus, Ranarilalatiana, Tolotra & Bergsten, Johannes, 2019

Ranarilalatiana, Tolotra & Bergsten, Johannes, 2019, Discovery of a specialist Copelatinae fauna on Madagascar: highly ephemeral tropical forest floor depressions as an overlooked habitat for diving beetles (Coleoptera, Dytiscidae), ZooKeys 871, pp. 89-118 : 98-101

Madaglymbus semifactus sp. nov. Figs 1D , 3A

Type locality.

Betampona Réserve Naturelle Intégrale (RNI) [17.9160S, 49.1999E] (Madagascar, Atsinanana region, Toamasina II)

Type material.

Holotype ♂ GP (NHRS): // NHRS-JLKB | 000065445 // Madagascar: Toamasina II: Betampona | RNI: MAD17-01: Vohimarangitra: | S-17.91604; E49.19986; 525 m: Dried | up forestpools in preaseape track: | 01/03/2017; Leg. T. Ranarilalatiana // Holotype | Madaglymbus semifactus sp. nov. | Det. Ranarilalatiana | & Bergsten, 2019 //

Paratypes: -4♂ GP, 7♀ (NHRS, DEUA & PBZT/MBC): // NHRS-JLKB | 000066233, 66235-41, 66297-9 // Madagascar: Toamasina: Atsinanana | Betampona RNI: lowalt rainforest | Path PPR, ca 100 m in from path PP | Dried out forest floor depression | MAD18-66: 24.II.2018 | 17.9160S, 49.1999E, 520 m | Leg. J. Bergsten & T. Ranarilalatiana // Paratype | Madaglymbus semifactus sp. nov. | Det. Ranarilalatiana | & Bergsten, 2019 //

-2♀, 1♂ GP, 4♀ (Alc.) (NHRS): // NHRS-JLKB | 000065446-7, 65456, 65448 (Alc.) // Madagascar: Toamasina II: Betampona | RNI: MAD17-01: Vohimarangitra: | S-17.91604; E49.19986; 525 m: Dried | up forestpools in preaseape track: | 01/03/2017; Leg. T. Ranarilalatiana // Paratype | Madaglymbus semifactus sp. nov. | Det. Ranarilalatiana | & Bergsten, 2019 //

-2♀, 4♀ (Alc.) (NHRS): // NHRS-JLKB | 000065442-3, 65444 (Alc.) // Madagascar: Toamasina II: Betampona | RNI: MAD17-04: NW of park entrance: | S-17.93059; E49.20261; 321 m: Dried | up pools in Patsitsatra stream: | 03/03/2017; Leg. T. Ranarilalatiana // Paratype | Madaglymbus semifactus sp. nov. | Det. Ranarilalatiana | & Bergsten, 2019 //

-1♂ GP (NHRS): // NHRS-JLKB | 000065441 // Madagascar: Toamasina II: Analalava | reserve: MAD17-09: N of nursery | plants: S-17.70532; E49.45702; 75 m: | forest pools: 08/03/2017; Leg. T. | Ranarilalatiana // Paratype | Madaglymbus semifactus sp. nov. | Det. Ranarilalatiana | & Bergsten, 2019 //

Diagnosis.

A small Madaglymbus species, more oval than the two following species, with continuous outline between pronotum and elytra. Similar to M. johannis (Wewalka, 1982) but less elongate and easily distinguishable by the punctured elytra, punctures that are much finer than in M. menalamba sp. nov. Penis in ventral view short and straight ( Fig. 3A ), not right-angled towards apex as in M. johannis .

Description.

Body length: 3.7-4.2 mm (♀: 3.7-4.2 mm, ♂: 3.9-4.1 mm).

Body shape broadly oval with a continuous outline laterally between pronotum and elytra ( Fig. 1D ).

Head and pronotum rufous, infuscated inside eyes and vaguely medially on pronotum. Elytra infuscated medially but with testaceous sections basally, laterally and apically. Appendages testaceous except metatarsus rufotestaceous.

Elytra and pronotum covered with fine punctures, much finer than in M. menalamba sp. nov, but a distinguishing feature compared with the smooth elytra of M. johannis . Punctures on pronotum concentrated laterally with only micropunctures medially. Lateral marginal bead on pronotum thin and present only in posterior half. Head, pronotum and elytra with same type of microreticulation and micropunctures.

Ventral side rufotestaceous, metacoxal plate and abdominal sternites II–IV with few fine strioles laterally. Metacoxal lines absent. Anterior metaventral process broad.

Male pro and mesotarsal segments I–III dilated and ventrally equipped with adhesive discs (constellation I:3, 4, II:4, III:4). Anterodistal angle of protarsal segment IV with a modified stout seta.

Penis bilobed with ventral lobe extending to near, but stops before, apex of dorsal lobe. Penis straight, short and pointed with a thin apex in ventral view, straight and evenly tapering towards apex in lateral view ( Fig. 3A ). Compared with the longer and thinner penis of M. johannis , M. semifactus sp. nov. has a shorter and straighter penis, neither right-turned at apex in ventral view nor downturned in lateral view. Parameres with a rather long but broad apical extension ( Fig. 3A ).

Female similar to male.

Distribution.

Known from Betampona RNI and at Analalava reserve, eastern lowland Madagascar ( Fig. 4B ).

Ecology and conservation.

The species was found in Betampona RNI and collected under the same circumstances as C. betampona sp. nov. ( Fig. 5 ). One specimen was collected from Analalava reserve in forest pools after a cyclone with heavy rain.

Etymology.

“Semifactus” means half-done or half-finished here referring to that this species is possibly less modified to spending time on land compared to next two Madaglymbus species.

Figures

Figure 1. Habitus, dorsal view. A Copelatus amphibius sp. nov. (female) B Copelatus zanatanensis sp. nov. (female) C Copelatus betampona sp. nov. (female) D Madaglymbus semifactus sp. nov. (female) E Madaglymbus kelimaso sp. nov. (male) F Madaglymbus menalamba sp. nov. (female).

Figure 3. Male genitalia. From left to right aedeagus in right lateral, ventral, left lateral views, and left paramere. A Madaglymbus semifactus sp. nov. B Madaglymbus kelimaso sp. nov. C Madaglymbus menalamba sp. nov.

Figure 4. Maps of Madagascar with species distributions and administrative divisions. A Copelatus amphibius sp. nov. (circle), Copelatus betampona sp. nov. (square) B Copelatus zanatanensis sp. nov. (circle), Madaglymbus semifactus sp. nov. (square) C Madaglymbus kelimaso sp. nov. (circle), Madaglymbus menalamba sp. nov. (square) D current 22 regions and six former provinces of Madagascar.

Figure 5. Habitat photo of locality MAD 18 - 66, Betampona RNI. The three new species Madaglymbus kelimaso sp. nov., Madaglymbus semifactus sp. nov., and Copelatus betampona sp. nov. were found in this terrestrial habitat.