Macrobrachium
Creators: name: Valencia, Diego M.
name: Campos, Martha R.
Publisher: name: Zenodo
Year: 2007
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Palaemonidae
Macrobrachium

description: Key to species of Macrobrachium from Colombia
1. Second pair of pereopods different in shape (Fig. 7 C, D)...........................................................................2
— Second pair of pereopods similar in shape (Fig. 6 C, D)..............................................................................6
2. Larger second pereopod with carpus shorter than merus (Fig. 7 C)............................................................3
— Larger second pereopod with carpus as long as or longer than merus (Fig. 9 C).........................................4
3. External surface of palm of large chela of second pair of pereopods with rectangular space densely pubes- cent (Fig. 11 C) ........................................................................................................................... M. hancocki
— External surface of palm of large chela of second pair of pereopods without densely pubescent rectangular space (Fig. 7 C) ....................................................................................................................... M. crenulatum
4. Ventral margin row of palm of larger second pereopod with smaller spines on the base of finger (Fig. 8 C)......................................................................................................................................................................5
— Ventral margin row of palm of larger second pereopod with smaller spines on midpalm length (Fig. 9 C).. .................................................................................................................................................. M. faustinum
5. Palm of larger second pereopod swollen with ventral margin strongly convex with external and internal surfaces of palm thickly pubescent (Fig. 14 C) ............................................................................ M. olfersii
— Palm of larger second pereopod compressed with ventral margin straight or nearly convex with external and internal surfaces of palm less pubescent (Fig. 8 C) ................................................................ M. digueti
6. Second pair of pereopods with merus longer than palm (Fig. 2 C)..............................................................7
— Second pair of pereopods with merus shorter than palm (Fig. 3 C)...........................................................10
7. Rostrum as long as or longer than scaphocerite (Fig. 15 A, 2 A).................................................................8
— Rostrum shorter than scaphocerite (Fig. 16 A) ............................................................................. M. praecox
8. Merus shorter than carpus (Fig. 2 C)........................................................................................................... 9
— Merus same length as carpus (Fig. 18 C)........................................................................................ M. reyesi
9. Upper margin of rostrum convex on orbital region (Fig. 2 A) ............................................. M. amazonicum
— Upper margin of rostrum straight on orbital region (Fig. 15 A) ............................................ M. panamense
10. Second pair of pereopods with carpus shorter than merus (Fig. 3 C).........................................................11
— Second pair of pereopods with carpus longer than merus (Fig. 1 C)..........................................................12
11. Fingers of second pair of pereopods longer than palm (Fig. 5 C). .............................................. M. carcinus
— Fingers of second pair of pereopods as long as or shorter than palm (Fig. 3 C) .................. M. americanum
12. Fingers of second pair of pereopods thickly pubescent (Fig. 1 C)..............................................................13
— Fingers of second pair of pereopods slightly pubescent or without pubescence (Fig. 4 C)......................15
13. Fingers of second pair of pereopods less than half of palm length (Fig. 17 C) ........................ M. rathbunae
— Fingers of second pair of pereopods more than half of palm length (Fig. 1 C)..........................................14
14. Carpus of second pair of pereopods less than 10 times as long as wide (Fig. 1 C)................ M. acanthurus
— Carpus of second pair of pereopods more than 10 times as long as wide (Fig. 20 B)................ M. tenellum
15. Cutting edge of fingers of second pair of pereopods with row of small teeth of similar size from base to midportion or beyond (Fig. 12 C)...............................................................................................................16
— Cutting edge of fingers of second pair of pereopods without row of teeth of similar size (Fig. 4 C).......17
16. Palm of second pair of pereopods less than 4.5 times as long as wide (Fig. 21 C)............ M. transandicum
— Palm of second pair of pereopods more than 4.5 times as long as wide (Fig. 12 C) ............ M. heterochirus
17. Palm of second pair of pereopods more than 9 times as long as wide (Fig. 10 C) ...................... M. ferreirai
— Palm of second pair of pereopods less than 7 times as long as wide (Fig. 4 C) …....................................18
18. Carapace without spinules on anterolateral surface (Fig. 6 A) ...................................................... M. cortezi
— Carapace with spinules on anterolateral surface (Fig. 4 A)........................................................................19
19. Palm of second pair of pereopods strongly swollen, less than 3 times as long as high and with spines of different size on internal margin (Fig. 13 C, D) ......................................................................... M. nattereri
— Palm of second pair of pereopods subcylindrical, more than 3 times as long as high and with spines of similar size on internal margin (Fig. 4 C, D) ............................................................................ M brasiliense
description: Published as part of Valencia, Diego M. & Campos, Martha R., 2007, Freshwater prawns of the genus Macrobrachium Bate, 1868 (Crustacea: Decapoda: Palaemonidae) of Colombia, pp. 1-44 in Zootaxa 1456 on pages 3-4, DOI: 10.5281/zenodo.176325