Macrobrachium faustinum (De Saussure, 1857 )

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 : 19

Macrobrachium faustinum (De Saussure, 1857)

Fig. 9 A–D

Material examined

Archipielago de San Andres y Providencia: Providencia Island, Pueblo Viejo stream, 4 Dec 1980, 3 males, 5 females, 2 ovigerous, INV 1232.

Magdalena: Santa Marta. Mamatoco stream, 18 Mar 1976, 1 male, 3 females, 1 ovigerous, INV 974.— Mamatoco stream, 18 Mar 1976, leg. G. Manjarréz, 2 males, 1 female, INV 4876.

Diagnosis

Rostrum nearly straight, apex curved downward, shorter than scaphocerite, slightly shorter or as long as antennular peduncle, upper margin with 12 to 14 teeth regularly spaced, including 4-5 teeth completely post orbital, lower margin with 3 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 1/3 of carpus. Second pair of pereopods prominent, different in shape and size, covered with conspicuous spines and long setae; the larger second pereopod overreaching scaphocerite with 1/3 of merus; merus 0.79 to 0.85 x carpus length, 0.76 to 0.84 x palm length; carpus 3.02 to 3.64 x as long as wide, and 0.97 to 0.98 x palm length; palm prominent with ventral margin convex, external and internal surfaces with conspicuous setae, ventral margin with row of spines, which are larger proximal and distally, smaller on the midportion; palm 3.32 to 3.86 x as long as wide; fingers strongly gaping when closed, thickly pubescent on recess, 0.93 to 1.19 x palm length, 1 or 2 prominent teeth on each proximal portion of cutting edge, followed by distal denticles.

Size. The largest male TL 44.7 mm, CL 14.1 mm; the largest female TL 57.2 mm, CL 17.4 mm; 3 ovigerous females were examined: TL 44.4 to 48.8 mm, CL 12.3 to 14.2 mm, with small and numerous eggs.

Remarks

This species is most similar to Macrobrachium olfersii ( Wiegmann, 1836) . The two can be distinguished by differences in the second pair of pereopods in adult males. The proximal and distal spines of the ventral margin row of the palm are larger, whereas they are smaller on the midportion in M. faustinum , however, they are of diminishing size distally in M. olfersii ; the spines and the pubescence on the external and internal surfaces of the palm, and the pubescence of the cutting edge of the fingers are less conspicuous in M. faustinum than in M. olfersii . The species Macrobrachium faustinum was reported from Arroyo Coquito, Parque Natural, Nacional Tayrona, and Córdoba River, department of Magdalena, and the specimens were deposited at INCODER by Martínez (1973). In a recent examination of Martinez’s material at INCODER, the specimens could not be found.

Figures

FIGURE 9. Macrobrachium faustinum (De Saussure, 1857), male, INV 1232: A, anterior part of body, lateral view; B, telson, dorsal view; C, larg second pereopod, lateral view; D, small second pereopod, lateral view.