Macrobrachium carcinus (Linnée, 1758) Fig. 5 A–C Cancer carcinus Linnée, 1758: 631. Macrobrachium carcinus, Holthuis, 1952: 114.— Chace & Hobbs, 1969: 93.— Chace, 1972: 20.- Martínez, 1973: 3.— Escobar, 1979: 107.— Rodríguez, 1980: 123.— Rodríguez, 1981: 45, 47.— Williams, 1984: 68.— Galvis, 1986: 447.— Abele & Kim, 1989: 6.— López & Pereira, 1996: 48.— Nizinski, 2003: 103.— Melo: 2003: 348. (For detailed synonymy refer to Holthuis, 1952). Material examined Atlántico: Piojó, Ciénaga El Totumo, 10 Apr 1970, leg. L. E. Martínez, 5 males, 2 females, INCODER, Cartagena.— Tubará, El Corral de San Luis, 1 Apr 1980, leg. F. Flórez, 1 male, 1 female, ICN-MHN-CR 0 852. Bolivar: Ciénaga de Turbaco, 28 Aug 1980, leg. H. Prahl, 1 ovigerous female, CRBMUV 80030. Córdoba: Lorica. Sinú River, 20 m asl, 5, 7 Jun 2004, leg. M. R. Campos, 4 males, 3 females, 1 ovigerous, ICN-MHN-CR 2125, 2129, 2130.— Sinú River, La Playa, 20 m asl, 6 Jun 2004, leg. M. R. Campos, 3 males, 6 females, 3 ovigerous, ICN-MHN-CR 2126, 2127. Chocó: Acandí. Monomacho stream, 15 m asl, 22 Aug 1995, leg. S. Usma, 2 males, ICN-MHN-CR 1594.— Sapzurro 50 m asl, 6 Aug 2004, leg. F. Jiménez, 1 female, ICN-MHN-CR 2183. La Guajira: Barrancas. Calabazo, near Cerrejón Mine, 600 m asl, 7 Jan 2004, leg. J. I. Mojica, 1 female, ICN-MHN-CR 2161.— Oreganal, Ranchería River, 200 m asl, 22 May 2004, leg. C. Castellanos, 8 males, 2 females, 25 juveniles, ICN-MHN-CR 2167.— Riohacha. south of Mingueo, 45 m asl, 27 Aug 1972, leg. J. Thomerson, 6 males, 5 females, ICN-MHN-CR 0045.— Ranchería River, 40 m asl, 9 Oct 2004, leg. C. Castellanos, 1 ovigerous female, 2 juveniles, ICN-MHN-CR 2210.— Ranchería River mouth, 40 m asl, 29 Nov 2003, leg. C. Castellanos, 1 ovigerous female, ICN-MHN-CR 2166.— Riohacha-Santa Marta, Highway, 50 m asl, 27 Aug 1972, leg. P. Cala, 1 ovigerous female, ICN-MHN-CR 0046.— Riohacha, km 20 southern, 50 m asl, 27 Aug 1972, leg. P. Cala, 2 males, 3 females, ICN-MHN-CR 2090.— Guerrero River, 47 m asl, 27 Aug 1972, leg. P. Cala, 10 males, 5 females, ICN-MHN-CR 2091.— Uribia, Cabo de la Vela, 22 May 1986, leg. E. Burbano, 9 juveniles, ICN-MHN-CR 1699. Magdalena: Without precise locality, 60 m asl, 17 Jul 1982, 3 males, INV 775.— Ciénaga Grande de Santa Marta, Estación Boquerón, 21 Mar 1989, leg. R. Reyes, 1 juvenile, ICN-MHN-CR 1174.— Santa Marta. Buritaca, 20 m asl, 20 Nov 1998, leg. R. Casallas & A. J. Bernal, 1 male, 1 ovigerous female, MLS 19.— Don Diego River, 1 female, 1 juvenile, INV 976.— Gaira River, 24 Jun 1971, leg. L. E. Martínez, 2 ovigerous females, INCODER, Cartagena.— Gaira River, Apr 1977, leg. Vásquez & Parody, 2 females, ICN- MHN-CR 0492.— Parque Nacional Natural Tayrona, Los Cedros, 3 - 7 Jul 1983, leg. G. Galvis, 4 males, 3 females, ICN-MHN-CR 0 531, 0 536, 0537.— Pozo Colorado, km 14. from Santa Marta, 29 Aug 1972, leg. J. Thomerson & P. Cala, 1 male, 3 females, ICN-MHN-CR 2092.— Pueblito, in stream, 27 Aug 1976, 1 male, 1 female, 1 juvenile, INV 980 Sucre: Colosó, Colosó creek, 150 m asl, 14 Nov 1985, leg. C. Román, 6 males, 1 female, ICN-MHN-CR 1470.— Toluviejo. Arroyo Pechilín, 13 Nov 1985, leg. C. Román, 1 male, ICN-MHN-CR 1732.— Arroyo Pechilín, 60 m asl, 17 Jul 1982, leg. A. Rocha, 2 female,1 ovigerous, ICN-MHN-CR 2093. Diagnosis Rostrum lanceolate, apex curved upward, as long as or shorter than antennular peduncle, upper margin with 11 to 14 teeth regularly spaced, including 4-5 teeth completely post orbital, lower margin 3 to 5 teeth; carapace smooth; abdomen smooth; telson terminal margin ending semicircular with one pair of internal and external reduced spines, not overreaching terminal margin of telson. First pair of pereopods overreaching scaphocerite with 2/3 to 3/4 of carpus. Second pair of pereopods elongated and prominent, similar in shape and size, overreaching scaphocerite with 1/3 of merus; merus 1.13 to 1.20 x longer than carpus, and 0.63 to 0.65 x palm length; carpus 1.74 to 2.20 x as long as wide and 0.53 to 0.57 x palm length; palm prominent, 2.90 to 3.57 x as long as wide, and 2.41 to 2.80 x as long as high; fingers 1.03 to 1.09 x longer than palm, gaping when closed, a prominent tooth on midcutting edge of mobile finger, and another one on proximal cutting edge of fixed finger, usually followed by 3 to 4 denticles on each base of finger. Size. The largest male, TL 193.7 mm, CL 62.7 mm; the largest female TL 155.9 mm, CL 51.4 mm; 8 ovigerous females were examined: TL 33.9 to 148.7 mm, CL 9.7 to 49.0 mm, with small and numerous eggs. Remarks This species is most similar to Macrobrachium americanum Bate, 1868, sometimes it is difficult to differentiate specimens of these two species. For this reason, Holthuis (1952) suggested that these two species should be considered as subspecies. However, in the Colombian material we found that these two species have differences in the length of the fingers of the second pair of pereopods: the fingers in M. carcinus are slightly longer than the palm, whereas they are as long as or slightly shorter than the palm in M. americanum. Some specimens of Macrobrachium carcinus were found at INCODER collection: 2 males, the largest male was TL 176.5 mm, CL 57.1 mm; 5 females, 3 of them ovigerous, the range of the ovigerous females were: TL 108.0 to 123.6 mm, CL 34.0 to 37.7 mm. These specimens were not recorded in this article because they lack location data. They may correspond to specimens reported by Martinez (1973), deposited at INCODER. In the material identified by Galvis (1986) as M. carcinus (ICN-MHN-CR 0535), we identified two specimens of M. heterochirus (Wiegmann, 1836) and one specimen of M. crenulatum Holthuis, 1950, the last one is actually labeled as ICN-MHN-CR 2118.

Published as part of Valencia, Diego M. & Campos, Martha R., 2007, Freshwater prawns of the genus Macrobrachium Bate, 1868 (Crustacea: Decapoda: Palaemonidae) of Colombia, pp. 1-44 in Zootaxa 1456 on pages 13-14, DOI: 10.5281/zenodo.176325