Macrobrachium transandicum 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 : 35-37

Macrobrachium transandicum Holthuis, 1950

Fig. 21 A–C

Diagnosis

Rostrum slightly sinuous, shorter than scaphocerite and antennular peduncle, upper margin with 9 to 11 teeth regularly spaced, including 5 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 total length of carpus. Second pair of pereopods similar in shape, different in size, covered with spines, the larger second pereopod overreaching scaphocerite with large portion of merus; merus 0.87 x carpus length and 0.80 x palm length; carpus 3.70 x as long as wide and 0.93 x palm length; palm 4.1 x as long as wide and 3.0 x longer than high; fingers not gaping when closed, cutting edge of fingers thickly pubescent, 0.67 x palm length, mobile finger with a prominent tooth on proximal portion of cutting edge, followed by 4 denticles distributed beyond midcutting edge, fixed finger with a series of 7 denticles of similar size, since proximal portion beyond midcutting edge.

Size. A male TL 62.9 mm, CL 20.9 mm; non-ovigerous females were examined. The females present small and numerous eggs ( Holthuis, 1952).

Remarks

The diagnosis is based on one adult male. The specimen almost agrees with Holthuis’s (1952) description. The differences are in the length of the rostrum and in the number of denticles on the cutting edge of the second pair of pereopods. The rostrum in Hothuis’s description is as long as or longer than scaphocerite, whereas it is shorter in the examined specimen. The cutting edge of fingers of the second pair of pereopods in Hothuis’s description have between 12 and 20 denticles, whereas they only show between 4 and 7 denticles in the examined specimen. Let us point out that Hothuis’s illustration and his description do not match exactly each other, because the rostrum of his ilustration is shorter than scaphocerite, similar to the by us examined specimen.

The species Macrobrachium transandicum was recorded from Cisneros, Dagua River, department of Valle del Cauca, and the specimens were deposited at the CRBMUV by Prahl et al. (1984). In a recent examination of Prahl et al. ’s material at the CRBMUV, the specimens could not be found.

Figures

FIGURE 21. Macrobrachium transandicum Holthuis, 1950, male, Universidad de los Andes: A, anterior part of body, lateral view; B, telson, dorsal view; C, second pereopod, lateral view.