Phylogenetic relationships among the species of the Cameroonian endemic freshwater crab genus Louisea Cumberlidge, 1994 (Crustacea, Brachyura, Potamonautidae), with notes on intraspecific morphological variation within two threatened species

Louisea yabassi from Ebo Forest, Cameroon, adult male (CW 20.2 mm) from site no. 1 (A, C, E, G), adult male (CW 21.3 mm) from site no. 2 (B, D, F, H). Louisea nkongsamba from Nlonako, Cameroon, adult male (CW 18.2 mm) from Eyimba (I, K, M, O), subadult male (CW 12.0 mm) from Enguegue (site no. 1) (J, L, M, P). A, B, I, J dorsal view of cephalothorax C, D, K, L frontal view of cephalothorax E, F, M, N ventral view of thoracic sternum G, H, O, P frontal view of left mandible. Scale bars: 8 mm (A, C, E); 9 mm (B, D, F); 1 mm (G, H); 4 mm (I, K); 12 mm (J, M); 3 mm (L); 8 mm (N); 2 mm (O, P).