Freshwater prawns of the genus Macrobrachium Bate, 1868 (Crustacea: Decapoda: Palaemonidae) of Colombia
Author
Valencia, Diego M.
Author
Campos, Martha R.
text
Zootaxa
2007
1456
1
44
journal article
10.5281/zenodo.176325
62d9dd43-d198-42fa-a471-7d51fa4f214d
1175-5326
176325
Macrobrachium hancocki
Holthuis, 1950
Fig. 11
A–D
Macrobrachium hancocki
Holthuis, 1950: 96
.
|
Macrobrachium hancocki,
Holthuis, 1952: 111
.—
|
Prahl |
et |
al.,1978: |
55.— |
Méndez, |
1981: 73.— Rodríguez, |
1981: |
47.— |
Prahl et al., 1984: 51.— Wicksten, 1989: 12. |
(For detailed synonymy refer to Holthuis, 1952). |
Material examined
Chocó:
Bahía Solano
,
22 May 1995
, leg. F. Montoya,
2 males
, ICN-MHN-CR 1794.
Cauca:
Guapi.
Gorgona Island.
13 Feb 1983
, leg. M. Alberico,
1 female
, CRBMUV 83077.— Gorgona Island,
22 May 1986
, leg. P. Cala,
5 males
, ICN-MHN-CR 1810.— Gorgona Island, La Azufrada stream,
27 May 1978
, leg. P. Cala,
3 males
,
1 female
, CRBMUV 78006.— Gorgona Island, in small creek at loading platform,
20 Jun 1979
,
1 male
, CRBMUV 79017.— Gorgona Island, in small creek,
6 Aug 1979
, leg. H. Prahl,
1 male
, CRBMUV 79033.— Gorgona Island, in south creek,
29 Mar 1980
,
2 males
, CRBMUV 80032.
Diagnosis
Rostrum straight, distal portion slightly curved downward, shorter than scaphocerite, as long as antennular peduncle, upper margin with 13 teeth regularly spaced, including 3-4 teeth completely post orbital, lower margin with 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 1/3 to 1/2 of merus; merus 1.24 to 1.31 x carpus length, and 0.84 to 0.96 x palm length; carpus 1.74 to 1.80 x as long as wide, and 0.64 to 0.77 x palm length; palm prominent, 2.01 to 2.49 x as long as wide, and 1.36 to 1.55 x as long as high, with rows of spines on external surface, between them a rectangular space thickly pubescent, in addition, a row of spines on lower margin which are smaller on base of finger, internal surface thickly pubescent; fingers strongly gaping when closed, cutting edges thickly pubescent, 0.86 to 1.0 x palm length, prominent tooth on each midportion of proximal cutting edge, usually followed by 2 small teeth on its base.
Size.
The largest male TL
60.2 mm
, CL
20.9 mm
; the largest female TL
50.9 mm
, CL
14.5 mm
. Ovigerous females were not examined. According to
Holthuis (1952)
the females present numerous and small eggs.
FIGURE 11.
Macrobrachium hancocki
Holthuis,1950
, male, ICN-MHN-CR 1810:
A
, anterior part of body, lateral view;
B
, telson, dorsal view;
C
, larg second pereopod, lateral view;
D
, small second pereopod, lateral view.
Remarks
This species is most similar to
Macrobrachium crenulatum
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, without spinulation, whereas the palm lacks this rectangular space in
M. crenulatum
.
The species
Macrobrachium hancocki
has been recorded from Calima River, department of Valle del Cauca, and specimens were deposited at CRBMUV by
Prahl
et al.
(1984)
. In a recent examination of Prahl
et al
’s material at the CRB- MUV the specimens could not be found.