Sharphydrus brincki, Bilton, 2013

Bilton, David T., 2013, A taxonomic revision of South African Sharphydrus, with the description of two new species (Coleoptera: Dytiscidae: Bidessini), Zootaxa 3750 (1), pp. 26-36 : 27

Sharphydrus capensis ( Omer-Cooper, 1955)

This species was originally described on the basis of two females, collected in the Lower Berg River in October 1950 by C. Harrison. I have studied the female holotype, deposited in the Natural History Museum, London, which is labelled as being collected in the Lower Berg River nr. Hermon, a locality which is at approx. 65 m a.s.l., ca. 25 km E of Malmesbury, to the North of Cape Town. Omer-Cooper (1966) refers to two other specimens which she considered to belong to this species, a male from Gydo Pass, 10 miles N of Ceres, and another from Alfreds Berg Pass in the Skurfteberg, 10 miles NNW of Ceres. Both of these were collected on the Lund University Expedition to South Africa in 1951. I have studied the first of these males, which is housed in the Lund University Museum, Sweden, and find that it does not in fact belong to S. capensis , having much stronger elytral keels than this species, as well as being somewhat larger and darker in colouration (see Fig. 1 ). This specimen, which is dissected with its genitalia dry mounted on the same card, is in fact a male of Sharphydrus brincki sp. nov., and is included as a paratype of this species below. In my collection I have a pair of the true S. capensis , collected from a stream near Theewaterskloof Dam on 31/xii/1991 by Paolo Mazzoldi. This locality is situated at approx. 300 m a.s.l., around 40 km E of Cape Town, to the South of Franschhoek (see Fig. 4 ). The male, and its genitalia, are illustrated here ( Figs 1C – 2C ). The male is slightly more shiny than the female, and the last joint of the fore and mid tarsi are slightly more elongated.

Figures

FIGURE 1. Habitus of A) Sharphydrus brincki sp. nov. B) S. kamiesbergensis sp. nov. C) S. capensis. D) S. coriaceus. Dorsal and lateral views. Scale bar = 1 mm.

FIGURE 2. Male genitalia of Sharphydrus species: median lobe in lateral and ventral view, right paramere of: A) S. brincki sp. nov.; B) S. kamiesbergensis sp. nov.; C) S. capensis; D) S. coriaceus. Scale bar = 0.5 mm

FIGURE 4. Distribution of Sharphydrus species in South Africa: yellow symbols S. brincki, green symbol S. kamiesbergensis, red symbols S. capensis, white symbols S. coriaceus. Closed circles indicate specimens examined, open circles records from the literature.