Nebrioporus solivagus ( Omer-Cooper, 1965 )

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 : 101-102

Nebrioporus solivagus ( Omer-Cooper, 1965)

Fig. 46

Potamonectes solivagus Omer-Cooper (1965: 140) (orig. descr.); Omer-Cooper (1965: 201) (male description). Nebrioporus (Zimmermannius) solivagus (Omer-Cooper) ; Nilsson & Angus (1992: 287); Nilsson (2001: 174).

Type locality. South Africa > Eastern Cape > Hanover [Hanover Road? In the eastern part of the Northern Cape].

Type material. According to the original description ( Omer-Cooper 1965), three type-specimens, 2♀♀ and 1 ♂, should stand in BMNH. I have been able to find only two in the Museum’s collection: 1 ♂, dissected, with some legs disarticulated and glued on the same card, bearing red, circular BMNH label " Holotype " and with the following data "E. Cape Province , Zwartberg, C. Chutter 1960 \ P. solivagus O-C., type M. Brit. Mus . 1978-308"; 1 ♀ bearing yellow circular BMNH label " Paratype ", with the following data "E. Cape Province, 435, Hanover, 24.I.1958 \ Potamonectes solivagus n.sp. det. J. Omer-Cooper, F. Brit. Mus. 1978-308". In spite of the circular type labels, the female from Hanover should be considered the holotype: one female from this locality, in fact, was designated as holotype in Omer-Cooper’s (1965) original description, while the male was described subsequently, in appendix in the same publication. I therefore add a red label " Holotype " to the female specimen and a yellow " Paratype " label to the male .

Additional material examined. Lesotho: Sani Pass , shallow well vegetated ponds by roadside on road before border post, 2864 m, 10.II.1997, leg. C.R. Turner (7 exs. CTP) .

Description. TL 5.4–5.5 mm; MW 2.7–2.9 mm. Externally very similar to N. vagrans (see below), from which can be separated by the following characters: body form slightly more elongate, dorsal colouration paler. Discal maculae on pronotum poorly developed and elytral vittae thinner and diffuse. Prosternal process keeled and bordered, with acuminate tip ( Fig. 46c). Legs completely testaceous, tarsi not darkened.

Male: posterior angles of pronotum rounded. Foreclaws unmodified ( Fig. 46d). Median lobe of aedeagus ( Fig. 46e) dorsally more straight than in N. vagrans ; parameres ( Fig. 46f) apically broader and rounded.

Female: Posterior angles of pronotum acute, lateral sides of pronotum more visibly bordered than in male.

Habitat. The only habitat data available is from C.R. Turner (personal communication, 2007), who encounter this species in a pair of pools at high altitude just inside the Lesotho border. These pools were shallow (<30cm deep) and fairly well vegetated with emergent and aquatic vegetation, suggesting the pool was seasonal.

Distribution ( Fig. 57): Southern Africa: known, at present, only for the type locality and Lesotho (at the border with Kwazulu-Natal). First record for Lesotho.