Macrobrachium cortezi Rodríguez, 1982

Valencia, Diego M. & Campos, Martha R., 2007, Freshwater prawns of the genus Macrobrachium Bate, 1868 (Crustacea: Decapoda: Palaemonidae) of Colombia, Zootaxa 1456, pp. 1-44 : 15

Macrobrachium cortezi Rodríguez, 1982

Fig. 6 A–D

Macrobrachium cortezi Rodríguez, 1982: 383 .

Material examined

Amazonas: Leticia, Corregimiento La Pedrera, La Tonina stream, 120 m asl, 6 Nov 1994, leg. M. R. Campos, 1 female, ICN-MHN-CR 2188.

Guainía: Inírida, Agujón creek, 70 m asl, 23 - 25 Mar 1998, leg. M. R. Campos, 11 males, 13 females, 7 ovigerous, 24 juveniles, ICN-MHN-CR 1691.— Pajarito creek, 70 m asl, 21 Mar 1998, leg. M. R. Campos, 11 males, 8 females, 7 ovigerous, ICN-MHN-CR 1688.— La Ceiba Community, Seje creek, 80 m asl, 18 Mar 1998, leg. M. R. Campos, 1 male, 1 ovigerous female, ICN-MHN-CR 1680.— Mañoco creek, 75 m asl, 25 Mar 1998, leg. M. R. Campos, 1 male, 4 females, 1 ovigerous, ICN-MHN-CR 1695.— Yucuta creek, 70 m asl, 24 Mar 1998, leg. M. R. Campos, 3 males, 7 females, 1 ovigerous, ICN-MHN-CR 1693.

Vaupés: Taraira, Serranía Taraira, 185 m asl, 22 Nov 1994, leg. M. R. Campos, 16 males, 21 females, 10 ovigerous, ICN-MHN-CR 1444.

Diagnosis

Rostrum nearly straight, slightly curved downward, overreaching with distal portion scaphocerite, upper margin with 10 to 12 teeth regularly spaced, including 2-4 teeth completely post orbital, lower margin 2 to 3 teeth; carapace smooth; abdomen smooth; telson terminal margin ending in sharp midpoint, flanked by two pairs of spinules, internal pair overreaching midpoint and external pair. First pair of pereopods overreaching scaphocerite with 2/3 of carpus. Second pair of pereopods elongated, similar in shape, different in size, covered with spines, which are prominent on ventral and internal surfaces; the larger pereopod overreaching scaphocerite with 1/3 to 1/4 of merus; merus 0.71 to 0.73 x carpus length, 0.56 to 0.66 x palm length; carpus 3.45 to 3.57 x as long as wide and 0.79 to 0.91 x palm length; palm subcylindrical, 3.34 to 3.81 x as long as wide, and 2.95 to 3.28 x as long as high; fingers strongly gaping when closed, 0.72 to 0.77 x palm length, prominent tooth on midcutting edge of mobile finger, followed by 3 small teeth to its base; cutting edge of fixed finger with a prominent tooth just behind of prominent tooth of mobile finger, followed by 3 small teeth to its base.

Size. The largest male TL 52.6 mm, CL 14.5 mm; the largest female TL 40.5 mm, CL 11.4 mm; 27 ovigerous females were examined: TL 26.6 to 37.0 mm, CL 6.9 to 10.5 mm, with large and few number of eggs.

Remarks

These are the first records of Macrobrachium cortezi for Colombia. This species is most similar to M. nattereri ( Heller, 1862) . The two can be distinguished by differences in the carapace and the size of the adult males. The anterolateral surface of the carapace in M. cortezi is smooth; whereas it is covered by spinules in M. nattereri . The total length of the adult males in M. cortezi is shorter than 52.6 mm, whereas it reaches 70 mm in M. nattereri .

Figures

FIGURE 6. Macrobrachium cortezi Rodríguez, 1982, male, ICN-MHN-CR 1691: A, anterior part of body, lateral view; B, telson, dorsal view; C, larg second pereopod, lateral view; D, small second pereopod, lateral view.