REDESCRIPTION OF AFRICAN FRESH- WATER CRAB 



113 



ZMB 20161, Buea, 6f, 16. xi. 1892, coll. Preuss. ZMB 20195, 

 Buea, lm, If, coll. Preuss. ZMB 20199, Victoria, 4m, coll. 

 Preuss. ZMB 21300, river Sanaga, Douala grassland district, 

 1200 m, lm, 11. i. 1917, coll. Elbert. ZMB 21308, Douala, If, 

 coll. Thorbeke. CENTRAL AFRICAN REPUBLIC. RCM 

 55.399, Giako river, Bougua, 26.ii.1982, coll. L. de Vos & J. 

 Kempeneeus. RCM 53.086, near Bangui, 22.xii.1967. 

 SUDAN. NHM 1912.12.31.52, Nyonki Nile, 2030 feet, If, 

 hatchlings, 28. iv. 1912, coll. Sir F. T. Jackson. NHM 

 1912.12.31.53, Gondokoro, 1800 feet, 12. iv. 1912, coll. Sir F. 

 T. Jackson. NHM 1913.9.10.1-3, Lado Nipo, 15 miles north 

 of Kojokaji, coll. S. S. Flower, zoological survey of Egypt. 

 NHM 1913.9.10.9-10, new cut to Zeraf, north of Shamfe, 

 coll. G. W. Graham. NHM 1918.12.13.1-3, Mongalla, coll. 

 S. S. Flower, Zoological Survey of Egypt. NHM 

 1922.11.22.7-11, Mongalla, Kanisa, vi.1914, coll. S. S. 

 Flower, Zoological Survey of Egypt. FMC, 400 miles west of 

 Juba, 7m, 18f, 22.xii.1884. ZAIRE. RCM 1666, Buta, 1934, 

 coll. F. Hutsebout. RCM 1.661-1.665, Bambesa, l.viii.1924, 

 coll. J. Brejko. RCM 47.495, Epulu, ix.1956, coll. Dr. M. 

 Poll. RCM 46.159-46.160, Ngense, 1955. RCM 

 46.161^16.162, Ngense, 1955. MNHN BP5049, river Dougou, 

 affluent of Uele, lm, coll. L. Didier, Mission du Bourg 

 Bozas, 1903. MCZ 10612, Faradje, lm If, 21-23. ix. 1915. 

 SMF 2405, Luki, coll. E. Dartevelle. SMF 2398, Ganda 

 Sundi, coll. E. Dartevelle. SMF 2385, Faradje, upper Uele, 

 v.1925, coll. Dr. Schoudeten (exchange, RCM 1083, 1079). 

 SMF 2383, Bambesa, coll. Krydag. SMF 1782, Duma, coll. 

 Telinbotz. All of the following AMNH material coll. H. 

 Lang, J. Chapin, AMNH Congo Expedition. AMNH 3338, 

 Faradje, 5m, 2f. AMNH 3339, Faradje. AMNH 3355, 

 Faradje, 3m. AMNH 3357, Faradje, 3m, If, x.1912. AMNH 

 3358, affluents of Nepoko river, near Gamangui (Ituri For- 

 est), 3m, If. AMNH 3359, Banana, 3m. AMNH 3359, Poko, 

 lm, 4f, x— xii.1913. AMNH 3377, affluents of Nepoko river, 

 near Gamangui (Ituri Forest), 3m, If. AMNH 3406, south of 

 Poko, x-xii.1913. AMNH 3409, affluents of Nepoko river, 

 near Gamangui (Ituri Forest), lm. AMNH 3422, Van Kerck- 

 hoverville, 2m, If, iv.1912. AMNH 3448, Faradje, If, 1911. 

 AMNH 3453, Poko, lm, 4f, viii.1909. AMNH 3458, north of 

 Ganza, If (ovig), 16.xii.1909. AMNH 3462, affluents of the 

 Tshope river, near Stanleyville. AMNH 3465, Yakukuku, 

 lm; Garamba, If, xi.1911. BIOKO. NHM 1905.7.19.12, coll. 

 Fernando Po Exploration Committee. ZMB 20164, lm, If, 

 vii.1900, coll. Conradt. GABON. NHM 1908.6.2.22, Lam- 

 barene, Ogoue river, coll. M. Ansorge. NHM 

 1908.6.2.23-24, Abanga river, Ogoue river. NHM 

 1908.6.2.25, Fang forest, Ogoue river, caught on a mountain- 

 top during heavy tropical rain, 29. iv. 1907. NHM 

 1908.6.2.25a, Masoma river, Ogoue river. AMNH 3367, 

 Libreville, 5m, 5f, ii.1916, coll. H. Lang, J. Chapin. AMNH 

 3369, 3m, 2f, 1916, coll. H. Lang, J. Chapin. FMC, Gabon or 

 Middle Congo, French Equatorial Africa, 1951-1952, coll. H. 

 A. Beatty. CABINDA. MNHN BP5048 (lm, CW 54.7, CL 

 36.0 mm), BP5047 (If, CW 56.6, CL 39.5 mm) Landana, 

 Cote de Loango, 4.ix.l898, coll. M. Petit. ANGOLA. NHM 

 1912.4.2.1-3, Luali river. 



DESCRIPTION OF MALE LECTOTYPE 



Carapace (Fig. 1 a,b). Ovoid, extremely wide, widest in 



anterior third (CW/CL = 1.51), extremely high, with maxi- 

 mum height in anterior region (CH/CL = 0.61). Anterior 

 margin of front straight, curving under, front relatively 

 narrow, about one-quarter carapace width (FW/CW = 0.25). 

 Surface of carapace smooth with no deep grooves. Postfron- 

 tal crest consisting of fused epigastric, postorbital crests, 

 lateral ends with slight crenulations; mid-groove broad, shal- 

 low. Postfrontal crest contrasting colour to carapace, located 

 very close to, almost touching, postorbital margin; laterally, 

 postfrontal crest meeting, or nearly meeting, anterolateral 

 margin of carapace at, or near, epibranchial tooth. Exo- 

 orbital tooth blunt, low, intermediate tooth smaller than 

 exo-orbital tooth, epibranchial tooth small, low, a granule. 

 Anterolateral margin of carapace raised and granulated, 

 bigger granules at epibranchial corner, smaller granules 

 behind, continuous with posterolateral margin, or curving 

 slightly inward in hepatic region. Posterior margin about 

 two-thirds as wide as carapace width. 



Face of of carapace with 2 sutures, 1 longitudinal, 1 

 vertical, dividing face and sides into 3 parts (Fig. 1 b). 

 Longitudinal suture dividing suborbital, subhepatic regions 

 from pterygostomial region, beginning under inferior medial 

 margin of orbit, and curving backward across side. Short, 

 curving, vertical suture dividing suborbital region from sub- 

 hepatic region (Fig. 1 b); suture beginning beneath interme- 

 diate tooth, curving down to meet longitudinal suture, 

 marked by row of small rounded granules. Third maxillipeds 

 (Fig. 1 d) filling entire oral field, except for transversely oval 

 efferent respiratory openings at superior lateral corners; long 

 flagellum on exopod of third maxilliped; ishium of third 

 maxilliped smooth, with faint vertical groove; merus with 

 flanged edges. Mandibular palp 2-segmented, terminal seg- 

 ment single, undivided, small hard, hair-fringed flap at junc- 

 tion between segments (Fig. 2 a-c). 



PEREIOPODS (Fig. 1 f-i). Chelipeds of lectotype unequal, 

 right longer, higher than left. Dactylus of right cheliped not 

 arched, fingers enclosing long interspace when closed, palm 

 of propodus swollen. Fingers of right cheliped with 4 larger 

 teeth on lower digit and 4 larger teeth on upper digit, 

 interspersed with a series of smaller pointed teeth along their 

 lengths. Inferior margins of merus with rows of small teeth, 

 cluster of granules surrounding larger tooth at distal end. 

 Carpus of cheliped with 2 large pointed teeth on inner 

 margin, second smaller than first. Left cheliped similar to 

 right, but smaller in all respects. Walking legs (pereiopods 

 2-5) slender (Fig. 2 j), third pair longest, fourth pair shortest. 

 Posterior margin of propodus of walking legs serrated, dactyli 

 of walking legs tapering to point, each bearing rows of 

 downward-pointing sharp bristles; dactylus of fourth pair 

 shortest (Fig. 2 j). 



Underside. First transverse groove on sternum (between 

 sternal segments 2 and 3) complete; second groove (between 

 sternal segments 3 and 4) consisting of 2 small notches at sides 

 of sternum; sternum with conspicuous raised ridges at points 

 where chelipeds insert (Fig. 1 c). Segments 1-6 of abdomen 

 four sided, last segment triangular, sides indented, rounded 

 at distal margin (Fig. 1 e); segment 3 broadest, segments 3-7 

 tapering inwards (Fig. 1 e). 



Terminal segment of gonopod 1 long (2/3 as long as subtermi- 

 nal segment), first half straight continuation of subterminal 

 segment, second half curving outward, tapering to pointed tip; 

 terminal segment with raised lobe on the cephalic part, separated 



