Pterosthetops impressus Perkins & Balfour-Browne, 1994

Bilton, David T., 2014, New species and new records of Pterosthetops: eumadicolous water beetles of the South African Cape (Coleoptera, Hydraenidae), Zootaxa 3811 (4), pp. 438-462 : 459

Pterosthetops impressus Perkins & Balfour-Browne, 1994

A relatively widespread species of the mountains of the western part of the Western Cape, which can be quite abundant. New records are from wet rock faces below springs and beside streams.

Additional records: September 2002 Western Cape, Mitchell’s Pass nr. Ceres, seepages over rock— 1 ♂; September 2002 Western Cape, Bainskloof Pass above Wellington, seepages over rock beside RXX road on north side of pass— 1 ♂, 2 ♀; 18/ix/2008 Western Cape, Table Mountain National Park, seepage over rock beside M64 road above Silvermine— 3 ♂; 26/ix/2008 Western Cape, Du Toitskloof Pass, wet rock face— 1 ♂; 27/ix/2008 Western Cape, Western Cape, Table Mountain National Park, Table Mountain, seepage over rock beside stream in Valley of the Red Gods— 1 ♂; 25/ix/2009 Western Cape, Franschhoek Pass, wet rock face beside R45 road ( Fig. 6 B)—1 ♀; 25/ix/2009 Western Cape, Mont Rochelle above Franschhoek, seepage over sloping rock face beside stream @ 1,100 m— 4 ♂, 2 ♀; 24/ix/2010 Western Cape, Table Mountain National Park, Table Mountain, seepage over rock in Echo Valley ( Fig. 5 D)— 1 ♂, 3♀; 23/ix/2011 Western Cape, Cederberg, seepages over exposed rock @ 1,200 m, below Wolfberg Arch, beside Matjiesrivier-Wupperthal road ( Fig. 5 A)— 1 ♂, 1 ♀; 24/ix/2011 Western Cape, Cederberg, wet rock face below spring beside Algeria Waterfall— 1 ♂; 3/x/2013 Western Cape, Cederberg, wet rock face in permanent spring below Wolfberg Cracks—abundant. Distribution Fig. 9 .

Figures

FIGURE 5. Habitats of Pterosthetops species. A) Cederberg, seepage over sloping rock beside stream @ 1,200 m below Wolfberg Arch, beside Matjiesrivier-Wupperthal road— P. coriaceus sp. nov., P. hawequas, P. impressus; B) Witzenberg, Michell’s Pass, wet rock face along R 46 road - P. baini sp. nov., P. hawequas, P. impressus (arrow indicates larva of Aspidytes niobe Ribera, Beutel, Balke & Vogler, 2002); C) Cederberg, Uitkyk Pass, seepages over rock face beside road— P. harrisoni, P. hawequas, P. impressus, P. pulcherrimus sp. nov., P. tuberculatus sp. nov., P. uitkyki sp. nov.; D) Table Mountain, seepage over rock in Echo Valley— P. equestrius, P. impressus. Photos D T & R Bilton.

FIGURE 6. Habitats of Pterosthetops species. A) Middelberg Pass, seepages over rock with algae on R 303 road above Blinkwater— P. hawequas, P. tuberculatus sp. nov.; B) Franschhoekpas, 500 m wet rock face formed by stream beside R 45 road— P. hawequas, P. impressus, P. tuberculatus sp. nov.; C) View along Great Escarpment from Vanrhyns Pass— P. hawequas was abundant on seep below tree at bottom left of photo. Photos D T Bilton.

FIGURE 9. Distribution of Pterosthetops species in the Western Cape: closed white symbol P. baini sp. nov., blue symbol P. coriaceus sp. nov., green symbols P. harrisoni, open white symbols P. impressus, red triangle P. harrisoni, P. hawequas, P. impressus, P. pulcherrimus sp. nov., P. uitkyki sp. nov. & P. tuberculatus sp. nov. Basemap source: ESri, GigitalGlobe, GeoEye, i-cubed, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, Swisstopo and the GIS User Community.