A systematic review of Rhinopetitia Géry (Teleostei, Characiformes, Characidae) with descriptions of four new species and redescription of R. myersi Géry Menezes, Naércio A. Netto-Ferreira, Andre L. Zootaxa 2019 2019-11-18 4700 1 59 86 Menezes & Netto-Ferreira, 2019 Menezes & Netto-Ferreira 2019 [151,424,1153,1180] Actinopterygii Characidae Rhinopetitia Animalia Characiformes 13 72 Chordata species oligolepis sp. nov.   Figs. 14–17, Table 3     Holotype. MZUSP 124120, female 27.0 mm SL: Brazil, Pará, Novo Progresso, Rio Jamanxim, Rio Tapajósbasin, 07°43’51”S, 55°16’36”W, J. Birindelli, L. Sousa, A. L. Netto-Ferreira, M. Sabaj, N. Lujan,  23 October 2007.    Paratypes. Allfrom Brazil:  INPA 59018, 3(all 22.0 mm SL),  MNRJ 51534, 3(30.0-33.0 mm SL),  MPEG 38602, 3(23.0–25.0 mm SL),  MZUSP 97306, 15(21.0–25.0 mm SL, 5 C&S, 23.0–25.0 mm SL),  UFRGS 27591, 3(22.0–24.0 mm SL), collected with the holotype;  MZUSP 124119, 1 female, 36.0 mm SL, Mato Grosso, Rio Xingubasin, Gaúcha do Norte, Rio Curisevo, 13°12’58”S, 53°29’53”W. C. Moreira, I. Landim, A. Datovo& Oliveira,  19 October 2004.   Diagnosis.  Rhinopetitia oligolepiscan be differentiated from its congeners by having 4 versus5 longitudinal scale rows between the dorsal-fin origin and the lateral line. It has the body as deep as in  Rhinopetitia nigrofasciata(body depth 19.2–24% of SL, and 20.0–24.8 of SL, Fig. 4, Tables 4and 5), but lower than in  R. myersi(26.3–31.1% of SL, Table 1,  R. paucirastra27.0–31.8% of SL, Table 2) and  R. melanohumeralis(25.0–30.4% of SL, Table 5).   Description.Morphometrics of holotypeand paratypesin Table 3. Body small (largest examined specimen 36.0 mm SL). Head and body elongate and laterally compressed; greatest body depth at dorsal-fin origin. Profile distinctly convex from upper jaw to posterior nostril, slightly convex from latter point to dorsal-fin origin, straight along dorsal-fin base, nearly straight to slightly concave from latter point to adipose-fin origin, and concave from latter point to anteriormost dorsal procurrent ray. Ventral body profile convex from tip of lower jaw to isthmus, nearly straight from that point to vertical through pectoral-fin origin, convex from latter point to pelvic-fin origin, and straight from that point to anal-fin origin. Ventral profile along anal-fin base straight and concave on caudal peduncle. Mouth sub-terminal to nearly inferior; lower jaw short, included in upper jaw when mouth closed. Posterior tip of maxilla reaching vertical through anterior border of pupil. Outer premaxillary tooth row with 4 (4), 5 (19*), or 6 (6) teeth, each with five cuspidate teeth (5), inner row with 4 (29) five (5) cuspidate teeth ( Fig. 15). Maxillary ( Fig. 15) with 2 (21), or 3 (8) teeth, anterior larger teeth with five cusps (5), smaller posterior teeth with 3 cusps (5). Dentary ( Fig. 15) with 4 (29), anterior large five cuspidate teeth (5), followed by 2 (1), 3 (10), or 4 (18), smaller five cuspidate teeth (5) gradually decreasing in size posteriorly. First gill arch with external and internal rows of gill rakers; external row with, 13 (7), 14 (10), 15 (9*) 16 (2), or 17 (1) gill rakers. Branchiostegal rays 4 (5); 3 originating on anterior and 1 on posterior ceratohyal. Scales cycloid. Lateral line complete; perforated scales 33 (1), 34 (6), 35 (15*), or 36 (3). Predorsal scales 11 (15), 12 (13*), or 14 (1). Scale rows between lateral line and dorsal-fin origin 4 (29); rows between lateral line and pelvic-fin origin (3); circumpeduncular scales 11 (6), 12 (16), or 13 (3*)13. Single series of scales with sinuous posterior borders forming sheath along base extending to about 12 thanal-fin ray.   FIGURE 14.  Rhinopetitia oligolepis, new species, MZUSP 124120, holotype, female, 27.0 mm SL, Brazil, Pará, Novo Progresso, Rio Jamanxim.   TABLE 3.Morphometric data for  Rhinopetitia oligolepis. Values for the holotype included in the range of female specimens. Standard length in mm; SD = Standard Deviation.    Holotype Males Females  pvalue  Characters n range mean SD n range mean SD  Standard length 27.0 3 24.0–25.0 24.3 0.5 26 20.0–27.0 23.7 3.0   Percentages of SL  Depth at dorsal-fin origin 22.2 3 22.9–23.3 22.0 0.7 26 19.1–24.0 21.7 1.4 0.248  Snout to dorsal-fin origin 53.0 3 54.0–54.1 54.1 0.1 26 50.0–56.5 53.3 1.6 0.297  Snout to pectoral-fin origin 22.2 3 24.0–24.0 24.0 0.0 26 22.2–26.4 24.5 1.2 0.322  Snout to pelvic-fin origin 48.1 3 48.0–48.3 48.1 0.2 26 46.0–50.0 48.6 1.0 0.339  Snout to anal-fin origin 63.0 3 64.0–65.4 64.8 0.7 26 61.1–66.5 64.4 1.5 0.331  Caudal peduncle depth 08.8 3 08.7–09.2 09.0 0.3 26 08.1–10.2 09.0 0.5 0.419  Caudal peduncle length 16.0 3 14.6–15.2 14.9 0.3 26 13.6–16.5 14.8 0.7 0.306  Pectoral-fin length 20.7 3 20.0–21.6 20.8 0.8 26 18.2–22.7 20.6 1.1 0.337  Pelvic-fin length 14.0 3 15.0–16.0 15.6 0.5 26 13.0–16.1 15.1 0.8 0.248  Dorsal-fin base length 11.1 3 11.6–13.0 12.0 0.4 26 11.1–13.3 12.2 0.6 0.422  Dorsal-fin height 22.2 3 23.0–24.0 23.3 0.6 26 21.7–25.0 23.0 0.9 0.437  Anal-fin base length 19.6 3 20.0–20.8 20.5 0.5 26 18.7–23.3 20.9 1.2 0.474  Anal-fin lobe length 17.7 3 17.0–17.9 17.4 0.5 26 16.1–19.0 17.5 0.7 0.400  Eye to dorsal-fin origin 43.0 3 38.7–41.6 40.1 0.4 26 35.7–43.0 39.7 1.7 0.432  Dorsal-fin origin to caudal-fin base 48.1 3 46.6–48.0 47.1 0.8 26 43.5–50.0 47.1 1.5 0.369  Bony head length 24.0 3 24.4–25.4 24.9 0.5 26 23.3–26.6 25.4 0.8 0.410   Percentages of HL  Horizontal eye diameter 41.5 3 38.3–41.0 39.6 1.3 26 37.9–42.1 40.2 1.4 0.488  Snout length 24.6 3 23.0–24.6 23.6 0.9 26 21.6–25.0 23.2 1.0 0.320  Least interorbital width 33.8 3 30.7–34.9 33.3 0.9 26 30.7–35.0 33.3 0.9 0.291  Upper jaw length 33.8 3 32.8–33.3 33.0 0.3 26 30.0–33.9 33.0 1.0 0.281 Pectoral-fin rays i,10 (1), 11 (5), 12 (19*), or 13 (4). Distal tip of longest pectoral-fin ray not reaching pelvicfin origin. Pelvic-fin rays i,6,i (29), tip of fin falling short of anal-fin origin. Supraneurals 5 (1) or 6 (4) rod shaped, or with discrete enlargement of dorsal portion; last supraneural located anterior to neural spines of 9 th(2) or 10 th(3) vertebral centra. Dorsal-fin rays ii,7,i (29). First dorsal-fin pterygiophore inserting behind neural spines of 11 th(3) and 12 th(2) centra. Distal margin of extended dorsal fin straight to slightly convex. Dorsal-fin origin closer to caudal-fin base than to snout tip. Base of last dorsal-fin ray situated slightly anterior to vertical through anal-fin origin. Anal-fin rays iv–v, 12 (2), 13 (3), 14 (3), 15 (6), (4), or 17 (1), posterior most ray adnate. Anal fin with short, inconspicuous, anterior lobe including last unbranched ray plus first 5–6 branched rays. Distal margin of anal fin concave. First anal-fin pterygiophore inserting behind haemal arch of centrum 17 th(5). Adipose fin present. Principal caudal-fin rays 10/9 (67). Dorsal and ventral procurrent rays 11(1), or 12 (4) and 11(3), or 12(2) respectively. Vertebrae 34 (1), and 35 (4).   FIGURE 15.  Rhinopetitia oligolepis, MZUSP 97063, 25.0 mm SL C&S, jaws and dentition, lateral view, left side, anterior at left.  Color in alcohol.Ground color pale to yellowish brown. Small dark chromatophores around mouth extends laterally to tip of maxilla and snout and up toward top of head except for a light area from tip of snout to fontanel; top of head behind light area dark with large concentration of small dark chromatophores; slightly larger chromatophores on upper portion of opercle and fourth, fifth and sixth infraorbital bones and upper and median portions of opercle; lower part of opercle with scattered dark chromatophores. Small dark chromatophores all over upper part of body above lateral line and scattered on lower part of body below lateral line. Mid-dorsal and adjacent longitudinal scale rows densely pigmented with small dark chromatophores distributed over whole scales, but leaving an unpigmented area near the border of each scale. Mid-line of predorsal scales with larger chromatophores. A dark mid-lateral stripe in freshly preserved specimens from about behind upper portion of opercle to caudal base extending through anterior part of median caudal-fin rays. All fins hyaline with scattered dark chromatophores on dorsal, caudal, and anal fins and very few on pectorals, and pelvic fins.   FIGURE 16.  Rhinopetitia oligolepis, MZUSP 97063, 25.0 mm SL C&S, sexually mature male; anal-fin rays, lateral view, left side, showing anal-fin hooks.   FIGURE 17.  Rhinopetitia oligolepis, MZUSP 97063, 25.0 mm SL C&S, sexually mature male; pelvic-fin rays, ventral view, left side, showing pelvic-fin hooks.  Sexual dimorphism.Mature males ( Fig. 16) with bilateral hooks on largest unbranched through fifth branched anal-fin rays. Pelvic fins of sexually mature males with hooks on all branched and last unbranched ray ( Fig. 17). Hooks absent on fins of mature females.   Etymology.The specific epithet  oligolepisis from the Greek words “oligo” meaning few and “lepis” meaning scale in reference to the fewer number of longitudinal scale rows from dorsal-fin origin to lateral line in this species.   Distribution.This species is known from small tributaries flowing into the Rio Tapajós and Rio Xingu basins, Brazil( Fig. 9). 2452381599 2007-10-23 MZUSP J. Birindelli & L. Sousa & A. L. Netto-Ferreira & M. Sabaj & N. Lujan Brazil Novo Progresso -7.7308335 Rio Tapajos 21 -55.276665 Rio Jamanxim 13 72 MZUSP 124120 1 Para holotype 2452381600 [199,516,1333,1359] Brazil All 13 72 1 paratype 2452381632 [529,912,1332,1360] INPA Brazil 13 72 INPA 59018, 3 1 paratype 2452381595 [926,1344,1332,1360] MNRJ Brazil 13 72 MNRJ 51534, 3 1 paratype 2452381613 MPEG Brazil 13 72 MPEG 38602, 3 1 paratype 2452381634 [488,1231,1368,1396] MZUSP Brazil 13 72 MZUSP 97306, 15 1 paratype 2452381630 UFRGS Brazil 13 72 UFRGS 27591, 3 1 holotype 2452381621 2004-10-19 MZUSP C. Moreira & I. Landim & A. Datovo & Oliveira Brazil Rio Xingu -13.216111 Rio Curisevo 21 -53.498055 Gaucha do Norte 13 72 MZUSP 124119 1 1 Mato Grosso paratype