Leporinus melanopleurodes, Birindelli & Britski & Garavello, 2013

Birindelli, José L. O., Britski, Heraldo A. & Garavello, Julio C., 2013, Two new species of Leporinus Agassiz (Characiformes: Anostomidae) from eastern basins of Brazil, and redescription of L. melanopleura Günther, Neotropical Ichthyology 11 (1), pp. 9-23 : 15-16

Leporinus melanopleurodes , new species Figs. 6 and 7

Holotype. MZUSP 100987 , 99.4 mm SL, Brazil, Bahia, Nilo Peçanha, rio das Almas, approximately 10 km from Nilo Peçanha on road Corredeiras do rio das Almas, 13°36’27.8”S 39°8’38.8”W, 12 Aug 2012, J. L. Birindelli, F. C. Dagosta, and M. V. Loeb.

Paratypes. All from Brazil, Bahia . ANSP 199122 , 2 , 86.8-95.2 mm SL ; MZUSP 111242 , 8 , 83.3-100.5 mm SL, collected with holotype . MCP 36965 , 8 , 79.8-128.7 mm SL ; MZUSP 109769 , 1, 116.7 mm SL, 1 CS, 89.5 mm SL; Laje, rio Jiquiriçá , near road BR-101, 13°10’18”S 39°19’15”W, 14 Oct 2004, J. F. Pezzi da Silva . MZUSP 109764 , 6 , 85.7-112.9 mm SL, Laje, rio Jiquiriçá , near road BR-101, 13°10’18”S 39°19’15”W, 13 Jul 2011, A. M. Zanata, J. L. Birindelli, P. Camelier , R. Burger & B. Sardeiro . MZUSP 111227 , 3 , 88.9- 113.2 mm SL, Laje, rio Jiquiriçá , near road BR-101, 13°10’18”S 39°19’15”W, 11 Aug 2012, J. L. Birindelli, F. C. Dagosta & M . V. Loeb .

Diagnosis. Leporinus melanopleurodes is distinguished from all congeners, except L. melanopleura , by having a single broad dark midlateral stripe on body, encompassing one or two scale rows of depth and centered on the scale row below lateral line. Leporinus melanopleurodes is further distinguished from congeners except Leporinus amae , L. arcus , L. amblyrhynchus , L. bistriatus , L. britskii , L. melanopleura , L. sexstriatus , L. striatus , L. taeniatus , L. taeniofasciatus , L. unitaeniatus and L. vanzoi , by the presence of a dark midlateral stripe on body. Leporinus melanopleurodes is additionally distinguished from Leporinus arcus , L. amblyrhynchus , L. britskii , L. sexstriatus , L. striatus , L. taeniatus , L. taeniofasciatus , L. unitaeniatus , and L. vanzoi , by having three scale rows between dorsal-fin origin and lateral line and three or 3.5 scale rows between lateral line and pelvic-fin origin (vs. four or five). Leporinus melanopleurodes is distinguished from Leporinus amae and L. bistriatus by having a single dark midlateral stripe on body encompassing two scale rows of depth and centered on the scale row below lateral line (vs. a dark midlateral stripe centered on lateral-line scale row, and a second dark stripe on dorsum), a dark blotch on caudal peduncle (vs. absent), and inferior mouth (vs. subinferior). Leporinus melanopleurodes is distinguished from L. melanopleura by having an inferior mouth (vs. subinferior), a dark adipose fin (vs. hyaline, red in life), and a conspicuous dark blotch on caudal peduncle (vs. dark blotch inconspicuous).

Description. Morphometric data in Table 2. Small size, relative to congeners. Largest examined specimen 128.7 mm SL. Head and body elongate and moderately compressed. Dorsal profile of head and body gently convex from snout tip to dorsal-fin origin, somewhat straight along dorsal-fin base, straight from terminus of dorsal-fin base to adipose-fin origin, and distinctly concave from adipose-fin origin to base of anteriormost procurrent ray of caudal fin. Ventral profile of head and body straight to slightly concave from lower jaw to vertical through posterior margin of opercle, gently convex from latter point to pelvic-fin origin, straight from pelvic-fin origin to anal-fin origin, somewhat straight along anal-fin base, and concave from terminus of anal-fin base to base of anteriormost procurrent ray of caudal fin. Greatest body depth at dorsal-fin origin.

Mouth inferior in all examined specimens (smaller specimen examined 79.8 mm SL), and longitudinally aligned with or slightly ventral to ventral margin of opercle. Snout rounded in lateral view, anteriorly blunt or slightly acute. Premaxilla with three incisiform teeth gradually decreasing in size from symphyseal tooth pair. Dentary with four incisiform teeth gradually decreasing in size posterolaterally ( Fig. 8 ).

Scales cycloid, with 8 (1), 9 (1), or 10 (1) radii. Lateral line complete with 36 (2), 37* (17), or 38 (2) perforated scales, extending from supracleithrum to base of median caudal-fin rays. Longitudinal scale rows between dorsal-fin origin and lateral line 3 (20). Longitudinal scale rows between lateral line and pelvic-fin origin 3* (15) or 3.5 (5). Longitudinal scale rows around caudal peduncle 12 (20). Predorsal scales from tip of supraoccipital spine to dorsal-fin origin 10 (13) or 11* (7).

Dorsal-fin rays ii,10 (20). Dorsal-fin origin slightly anterior to middle of standard length and to vertical through pelvic-fin origin; distal margin of dorsal fin rounded. Adipose fin small, teardrop-shaped with origin approximately at vertical through base of last anal-fin ray. Pectoral-fin rays i,13* (4), i,14 (13), or i,15 (3). Tip of pectoral fin almost extending to midpoint between origins of pectoral and pelvic fins; distal margin rounded. Pelvic-fin rays i,8 (20); distal margin of pelvic fin slightly convex. Anal-fin rays ii,8 (20); origin of anal fin approximately at vertical through posterior margin of fourth scale anterior to adipose-fin origin, rear of adpressed fin not reaching base of caudal-fin rays. Distal margin of anal fin approximately straight to slightly convex. Principal caudal-fin rays i,8,9,i (20). Caudal fin forked, lobes rounded, upper lobe slightly longer than lower lobe. Vertebrae 37 (5) or 38 (1).

Color in alcohol. Ground coloration of head and body brown or tan; weakly countershaded. Body with conspicuous dark midlateral stripe extending from immediately above posterior nares to end of caudal peduncle, and conspicuous dark oval blotch at posterior of caudal peduncle, encompassing approximately four scale rows of length and two of depth.Stripe broad, encompassing one to two scale rows of depth, and centered on scale row below lateral line, occupying one-half of lateral-line scale row, all of row below it and, sometimes, one-half of adjacent ventral row. Dark midlateral stripe particularly conspicuous in smaller specimens (up to 85 mm SL), and somewhat faded in larger individuals (100 mm SL or more).Ventral surfaces of head and belly pale to cream. Fins generally dusky, pelvic fin somewhat hyaline. Dark blotch on caudal peduncle, alternatively, somewhat inconspicuous in smaller specimens (up to 85 mm SL) but very conspicuous in larger individuals (100 mm SL or more).

Color in life. Life coloration similar to that described for preserved specimens, except for bright yellow fins ( Fig. 7 ), and dusky red spot on dorsal and distalmost portion of upper lip.

Distribution. Leporinus melanopleurodes is known from the rio das Almas and rio Jiquiriçá, two small coastal river in southern Bahia, Brazil ( Fig. 4 ). All examined specimens were collected in fast flowing rapids with clear water over a rocky bottom densely covered with Podostemaceae ( Fig. 9 ).

Etymology. The species name melanopleurodes is from melanopleura , in reference to Leporinus melanopleura , plus the suffix odes, meaning similar to, in allusion to the similarity between this new species and L. melanopleura . An adjective.

Figures

Fig. 6. Leporinus melanopleurodes: (a) holotype, MZUSP 100987, 99.4 mm SL, rio dasAlmas; (b) paratype, MZUSP 111242, 83.3 mm SL, rio Jiquiriçá; (c) paratype, MCP 36965, 128.7 mm SL, rio Jiquiriçá.Scale bars = 10 mm.

Fig. 7. Leporinus melanopleurodes: (a) paratype, MZUSP 111242, 87.4 mm SL, rio dasAlmas, (b) paratype, MZUSP 111227, 99.2 mm SL, rio Jiquiriçá [specimen lacking adipose fin], photographed live. Scale bars = 10 mm.

Fig. 8. Scanning electron image of the upper and lower jaws of Leporinus melanopleurodes, in lateral view, MZUSP 109769,89.5mmSL.

Fig. 4. Distribution of Leporinus melanopleura (triangles), L. melanopleurodes (square), and L. brinco (circles); type localities indicates by white symbols. River basins: (1) rio Jequitinhonha, (2) rio Pardo, (3) rio Una, (4) rio de Contas, (5) rio das Almas, (6) rio Jiquiriçá, (7) rio Paraguaçu, (8) rio Itapecuru, and (9) rio São Francisco.

Fig. 9. Rio dasAlmas, Bahia, Nilo Peçanha, at 13°36’27.8”S 39°8’38.8”W, type locality of Leporinus melanopleurodes.