POTAMONAUTES LIPKEI, A NEW SPECIES OF AFRICAN FRESHWATER CRAB (DECAPODA, POTAMONAUTIDAE) FROM SENEGAL BY ZDENEKˇ DURIŠˇ 1,3) and MILAN KOCH2) 1) Department of Biology and Ecology, Faculty of Sciences, University of Ostrava, Chittussiho 10, CZ-71000 Ostrava, Czech Republic 2) Gymnasium Orlová, Masarykova 1313, CZ-73514 Orlová-Lutyne,ˇ Czech Republic ABSTRACT A new species of West African freshwater crab of the genus Potamonautes is described from specimens collected in Senegal. The crabs were collected from burrows in the banks of small streams as well as from the nearby Gambia River in Niokolo Koba National Park. This new species is distinguished from Senegalese congeners by a combination of characters of the carapace, chelipeds, thoracic sternum, and gonopods. The new species is compared to other freshwater crabs from the family Potamonautidae found in West Africa. RÉSUMÉ Une nouvelle espèce de crabe d’eau douce ouest africain du genre Potamonautes est décrite à partir de spécimens récoltés au Sénégal. Ces crabes furent récoltés dans des terriers dans des bancs de petits ruisseaux aussi bien que dans la proche Gambia River dans le Parc National du Niokolo Koba. La nouvelle espèce se distingue de ses congénères sénégalais par un ensemble de caractères de la carapace, les pinces, le sternum thoracique et les gonopodes. La nouvelle espèce est comparée à d’autres crabes d’eau douce de la famille des Potamonautidae trouvés en Afrique de l’Ouest. INTRODUCTION The African potamonautid freshwater crab genus Potamonautes MacLeay, 1838, includes over 70 species (Ng et al., 2008) and is widely distributed throughout sub-Saharan Africa and the Nile Basin as far north as Cairo. Four species, P.ecorssei (Marchand, 1902), P.triangulus Bott, 1959, P.senegalensis 3) Corresponding author; e-mail: [email protected] © Koninklijke Brill NV, Leiden, 2010 Studies on Malacostraca: 219-229 220 CRM 014 – Fransen et al. (eds.), LIPKE BIJDELEY HOLTHUIS MEMORIAL VOLUME Bott, 1970, and P. re i d i Cumberlidge, 1999, are found in the region of West Africa from Senegal to Cameroon (Cumberlidge, 1999), a region which also has species of five other genera, Liberonautes Bott, 1955, Sudanonautes Bott, 1955, Globonautes Bott, 1959, Afrithelphusa Bott, 1959, and Potamonemus Cumberlidge & Clark, 1992 (Cumberlidge, 1999; Cumberlidge et al., 2008). Only two of the Potamonautes species listed above, P. senegalensis and P. ecorssei, have previously been reported from Senegal (Cumberlidge, 1999). The findings presented here arise from a new collection of freshwater crabs from Senegal made by researchers from the Institute of Vertebratology, Czech Academy of Sciences, Brno, Czech Republic. Among them, a new species of the genus Potamonautes was found. The species is described and illustrated here. The abbreviations used in this report are as follow: cw, carapace width (measured as the maximum width of carapace); ch, carapace height (measured as the distance between horizontal levels of the of the pterygostomian angle and the uppermost point of the carapace dorsum); cl, carapace length (mea- sured from the anterior level of the frontal lobes to the posterior margin); fw, frontal width (measured between the bases of the eyestalks); P1-P5, first to fifth pereiopods, respectively; G1-G2, gonopod 1 and 2, respectively; NHM, Nat- ural History Museum, London, UK; RMNH, Nationaal Natuurhistorisch Mu- seum — Naturalis (previously Rijksmuseum van Natuurlijke Historie), Leiden, the Netherlands. SYSTEMATIC PART Family POTAMONAUTIDAE Bott, 1970 Subfamily POTAMONAUTINAE Bott, 1970 Genus Potamonautes MacLeay, 1838 Potamonautes lipkei sp. nov. (figs. 1-3) Material examined. — Holotype male, NHM 2010. 272, cw 44.3 mm, allotype female, NHM 2010.273, cw 35.0 mm (bad condition, fragmentary), Mt. Assirik slope, Niokolo Koba ◦ ◦ National Park, Senegal, 12 53.091 N, 12 42.758 E, coll. P. Koubek, 20 November 2002. — Male paratype, RMNH D 53183, cw 32.3 mm, same locality, coll. P. Koubek, 16 February 2007. — Male paratype, NHM 2010.274, cw 27.9 mm: Gambia River embankment, Smenti (tourist ◦ ◦ centre), Niokolo Koba National Park, Senegal, 13 01.706 N, 13 17.855 E, coll. P. Koubek, 5 November 2004. Diagnosis. — Carapace moderately broad, dorsally convex, ch/fw 1.1. Front narrow, cw/fw 3.1. Postfrontal crest spanning entire carapace, lateral.