Cheirodontinae

Malabarba, Luiz R. & Jerep, Fernando C., 2014, Review of the species of the genus Serrapinnus Malabarba, 1998 (Teleostei: Characidae: Cheirodontinae) from the rio Tocantins-Araguaia basin, with description of three new species, Zootaxa 3847 (1), pp. 57-79: 75-76

publication ID

http://dx.doi.org/10.11646/zootaxa.3847.1.3

publication LSID

lsid:zoobank.org:pub:93242732-2B5A-4083-8EC5-6FA53BD83E7D

DOI

http://doi.org/10.5281/zenodo.4928410

persistent identifier

http://treatment.plazi.org/id/03BCEF20-EC12-FF89-FF68-F9A5FA00447C

treatment provided by

Felipe

scientific name

Cheirodontinae
status

 

Key to the species of the Cheirodontinae   occurring in the Atlantic drainages of northeastern Brazil, from the rio Tocantins-Araguaia to the rio Paraguaçú drainages

1. Lower lobe of caudal fin of males covered with cone shaped or papilla-like organs (see Malabarba et al., 2004: figs. 1 to 4). A conspicuous small black spot present at midlength of first branched anal-fin ray of males (see Malabarba et al., 2004: figs. 5–6 and 8). A dark brown nearly isosceles triangular shaped mark present in the area covering pelvic bone in males (see Malabarba et al., 2004: fig. 9)....................................................................2 ( Kolpotocheirodon   )

1´. Lower lobe of caudal fin of males not covered with cone shaped or papilla-like organs. Conspicuous black spots lacking on branched anal-fin rays. Triangular mark in area covering pelvic bone absent....................................... 3

2. Dorsal fin lacking conspicuous black spots. 3–5 very small, vertical bars crossing lateral body stripe between pseudotympanum and area ventral to dorsal fin (see Malabarba et al., 2004: fig. 8). Twelfth to the 14 th or 15 th principal caudal-fin rays of males bearing hooks................................................................................................... Kolpotocheirodon theloura   (headwaters of São Francisco and Paraná river basins near Brasília, DF, Brazil)

2´. Conspicuous small black spot present on soft tissue between midlength of first and second, and second and third dorsal-fin branched rays (see Malabarba et al., 2004: figs. 5 and 6). Vertical bars crossing lateral body stripe and hooks on caudal fin absent................................................. Kolpotocheirodon figueiredoi   (Paraguaçu River drainage)

3. Base of lower caudal-fin lobe with hypertrophied group of scales forming small pouch................................ Compsura heterura   (São Francisco River basin and northeastern coastal drainages; absent in Tocantins-Araguaia River basin)

3´. Base of lower caudal-fin lobe without hypertrophied scales................................................... 4

4. Ventral procurrent caudal-fin rays not hypertrophied or exposed along ventral margin of caudal peduncle of mature males. Thirteenth to 14 th caudal-fin rays bearing hooks associated with hypertrophied skin flaps in mature males ( Malabarba & Weitzman, 1999: figs. 3–6).................... Acinocheirodon melanogramma   (São Francisco and Jequitinhonha river basins)

4´. Ventral procurrent caudal-fin rays hypertrophied and exposed ventrally in mature males. Caudal-fin rays without hooks or hypertrophied skin flaps in mature males.................................................................. 5

5. First through fourth or fifth branched anal-fin rays of mature males slab-shaped ( Malabarba & Jerep, 2012: fig. 3). Distal tip of ventral procurrent caudal-fin rays conical in mature males ( Malabarba & Jerep, 2012: fig. 3). Anal-fin rays iv–v, 14–17. Lateral line completely pored with 32–36 scales................... Ctenocheirodon pristis   (Tocantins-Araguaia River basin)

5´. First through sixth or eighth branched anal-fin rays of mature males slab-shaped ( Fig. 4 View FIGURE 4 ). Distal tip of ventral procurrent caudal-fin rays spatulate or scimitar-shaped in mature males ( Fig. 2 View FIGURE 2 ). Anal-fin rays iii–iv,16–21.............. 6 ( Serrapinnus   )

6. Three central cusps of dentary teeth expanded relative to other cusps and form a sharp-cutting edge. Lateral line completely pored.................... Serrapinnus heterodon   (São Francisco River basin and northeastern Atlantic coastal drainages)

6´. Three central cusps of dentary teeth similar in shape to remaining cusps ( Figs. 3 View FIGURE 3 , 7 View FIGURE 7 , 9 View FIGURE 9 , 11 View FIGURE 11 ). Lateral line incomplete, with 5–10 pored scales (variable in S. tocantinensis   , ranging from 6–36 scales)............................................. 7

7. Longitudinal black stripe wide and conspicuous, one or one and half scale deep, extending from posterior margin of opercle to caudal spot ( Fig. 8 View FIGURE 8 ).................................................. S. sterbai   (Tocantins-Araguaia River basin)

7´. Longitudinal black stripe narrow, extending from region below dorsal-fin base to caudal spot......................... 8

8. Longest unbranched dorsal- and pelvic-fin rays of males prolonged as filament ( Fig. 10 View FIGURE 10 )........................................................................................... S. tocantinensis   (Tocantins-Araguaia River basin).

8´. Longest unbranched dorsal- and pelvic-fin rays of males not prolonged as filament.................................. 9

9. Ventral procurrent caudal-fin rays 17–19................................ S. lucindai   (Tocantins-Araguaia River basin)

9´. Ventral procurrent caudal-fin 16 or fewer.................................................................. 10

10. Ventral procurrent caudal-fin rays of mature males spatulate, forming keel along posterior ventral margin of caudal peduncle...................................... S. piaba   (São Francisco River basin and northeastern coastal Atlantic drainages)

10´. Ventral procurrent caudal-fin rays of mature males scimitar-shaped and forming semicircle, with portion of ventral procurrent caudal-fin rays having resultant star-shape form with multiple points ( Fig. 2a View FIGURE 2 ).................................... 11

11. Premaxillary teeth with 7 to 9 cusps ( Fig. 3a View FIGURE 3 )............................... S. aster   (Tocantins-Araguaia River basin).

11´. Premaxillary teeth with 5 cusps (see Jerep & Malabarba, 2014: fig. 3).......................................................................................... S. potiguar   ( Ceará-Mirim River basin in Rio Grande do Norte state)   .