Macrobrachium crenulatum Holthuis, 1950

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 : 16-18

Macrobrachium crenulatum Holthuis, 1950

Fig. 7 A–D

Macrobrachium crenulatum Holthuis, 1950: 95 .

Macrobrachium crenulatum, Holthuis, 1952: 107 .— Chace & Hobbs, 1969: 99.— Chace, 1972: 20.— Martínez, 1973: 11.— Escobar, 1979: 120.— Rodríguez, 1980: 123.— Abele & Kim, 1989: 8.

Macrobrachium carcinus, Galvis, 1986: 447 .

Macrobrachium olfersi, Galvis, 1986: 448 .

(For detailed synonymy refer to Holthuis, 1952).

Material examined

Bolivar: Between Matute - Turbaco, 6 May 1972, leg. L. E. Martínez, 1 female, INCODER, Cartagena. Chocó: Acandí, Monomacho stream, 15 m asl, 22 Aug 1995, leg. S. Usma, 2 males, ICN-MHN-CR 1595.— Sapzurro, 50 m asl, 6 Aug 2004, leg. F. Jiménez, 1 male, ICN-MHN-CR 2184. La Guajira: Riohacha, Negro River, 50 m asl, 27 Aug 1972, leg. P. Cala, 2 males, 1 female, ICN-MHN- CR 0044.— Km 3 south Riohacha, 50 m asl, 27 Aug 1972, leg. P. Cala, 2 males, ICN-MHN-CR 2117. Magdalena: Santa Marta, Parque Nacional Natural Tayrona, Los Cedros, 5 - 6 Jul 1983, leg. G. Galvis, 2 males, ICN-MHN-CR 0 532, 2118.— Parque Nacional Natural Tayrona, Piedras River, 1999, 1 male, Universidad de los Andes.

Diagnosis

Rostrum straight, apex nearly curved downward, shorter than scaphocerite, as long as antennular peduncle, upper margin with 11 to 14 teeth regularly spaced, including 4-5 teeth completely post orbital, lower margin 2 to 4 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 1/2 of carpus. Second pair of pereopods prominent, different in shape and size, covered with conspicuous spines; the larger second pereopod overreaching scaphocerite with ca. 1/3 of merus; merus 1.03 to 1.19 x carpus length, 0.86 to 1.0 x palm length; carpus 1.61 to 2.14 x as long as wide, and 0.72 to 0.89 x palm length; palm prominent with rows of spines, and slightly pubescent on external surface, ventral margin with row of spines, which decreasing in size to base of finger, 2.06 to 2.38 x as long as wide, 1.30 to 1.47 x as long as high; fingers strongly gaping when closed, cutting edges thickly pubescent, 0.98 to 1.21 x palm length, a prominent tooth on 1/4 of proximal portion of each cutting edge, followed by 2 to 3 small teeth on its base.

Size. The largest male TL 81.0 mm, CL 26.5 mm; the largest female TL 48.8 mm, CL 13.8 mm; non ovigerous females were examined. According to Holthuis (1952) the eggs of this species are small and numerous.

Remarks

This species is most similar to Macrobrachium hancocki Holthuis, 1950 . The two can be distinguished by differences in the second pair of pereopods in adult males. The external surface of the palm of the large chela of the second pair of pereopods in M. hancocki has a clearly differentiated pubescent rectangular space, devoid of spinulation, which is not present in M. crenulatum . One male of Macrobrachium carcinus ( Linnée, 1758) (ICN-MHN-CR 0535), and one male of M. olfersii ( Wiegmann, 1836) (ICN-MHN-CR 0532) from Santa Marta, Parque Nacional Natural Tayrona, Los Cedros, department of Magdalena, reported by Galvis (1986) are actually M. crenulatum (ICN-MHN-CR 2118, 0532).

Figures

FIGURE 7. Macrobrachium crenulatum Holthuis, 1950, male, ICN-MHN-CR 0532: A, anterior part of body, lateral view; C, larg second pereopod, lateral view; D, small second pereopod, lateral view. Male, ICN-MHN-CR 1595: B, telson, dorsal view;