Nebrioporus abyssinicus ( Sharp, 1882 )

Toledo, Mario, 2009, Revision in part of the genus Nebrioporus Régimbart, 1906, with emphasis on the N. laeviventris-group (Coleoptera: Dytiscidae), Zootaxa 2040, pp. 1-111 : 39-40

Nebrioporus abyssinicus ( Sharp, 1882)

Deronectes abyssinicus Sharp (1882: 431) (orig. descr.).

For a complete bibliography see Nilsson (1992; 1995a).

Material examined. Ethiopia: Simien , Debarec [Debark’, Simen mts.], c. 9800 ft., 11.XI.1952, from stream with steep earth banks and small falls, N . Ethiopia: 1952-1953. Hugh Scott. B.M. 1953-335 (8 exs. BMNH) .

Kenya: Nakuru, Elmenteita , 1.V.1967, E. S. Brown, 1468, ex coll. E. S. Brown 14-1972 (4 exs. OUMNH) ; Nakuru, Stream nr. Lumbwa , 2.IV.1967, E. S. Brown, 1441, ex coll. E. S. Brown 14-1972 (1 ex. OUMNH) ; Isi, SE Loitokitok, Narumore riv., 1800 m, 11.I.1994, leg. Zettel (10 exs. MTP, PMB) .

Tanzania: Arusha, Mt. Meru , 1800–2000 m, 6–7.IV.1997, leg. M. Kubon (1 ex. PMB) ; Mt. Kilimandjaro, NE Marangu, stream, 2200 m, 22.VII.1968 (15 exs. FPR) .

Description. see Nilsson (1992: 82).

Variability. According to Nilsson (1992: 85), populations from Mt. Kilimandjaro and Mt. Meru, in Tanzania, differ from Ethiopian specimens for the peculiar narrow pronotum in females and the darker colouration, specially on pronotum and head, which are almost totally black. Specimens from Isi, in Kenya (a locality that I have been unable to find, but likely to be located on the border between Kenya and Tanzania), do share the same features. This form was described by Régimbart (1908) as Hydroporus abyssinicus var. atratus (type locality Mt. Meru), and I agree with Nilsson (1992) in that subspecific rank should be given. Elsewhere in Kenya, Nakuru (some 330 km NW to Mt. Kilimandjaro) is the type locality of a second form of N. abyssinicus ( var. flavidus Régimbart, 1908 ). Non-type specimens examined from this locality are completely different from the dark populations of Mt. Meru, Kilimandjaro and Isi, with pale colouration (even paler than the typical Ethiopian N. abyssinicus ), completely reddish head and pronotum almost without markings, except where there is a darker line along the hind margin. Female pronota resemble those of the males, not narrower than base of elytra, and the general habitus of all examples appears slightly more depressed than in Ethiopian specimens (dorsally they look similar to N. solivagus ; see below). Male characters are more similar to those described in Nilsson (1992) for Tanzanian specimens, with fore claws almost equal in length, and parameres with pronounced ventral subapical angle, although not acute.

Distribution ( Fig. 56). Ethiopia, Kenya (Nakuru, Isi), Sudan (White Nile), Tanzania (Mt. Kilimandjaro, Mt. Meru).