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Hyphessobrycon itaparicensis Lima & Costa, 2001 Figs. 1-4, Tab. 1 Hyphessobrycon itaparicensis Lima & Costa, 2001: 233-234; 236-237. Type locality: small stream in Ilha de Itaparica. - Lima et al., 2003: 139 (list of species). - Buckup et al., 2007: 54 (list of species). - Menezes et al., 2007: 90 (list of species). - Zanata, Camelier, 2010: 771-772; 776 (diagnosis of H. brumado; comparative material). - García-Alzate et al., 2010: 58; 62 (diagnosis and comparison with H. sebastiani) - Burger et al., 2011: 274; 277; 279; 282; 285; 290 (occurrence of species on the Recôncavo Sul basin, Bahia State; photo; identification key; comparative material). - Carvalho, Langeani, 2013: 533 (comparative material). - Menezes et al., 2013: 29 (comments about conservation of type locality). - Brito et al., 2014: 1156-1159 (geographic distribution; photos; molecular identification). - Camelier, Zanata, 2014: 687; 690; 691; 692; 696 (list of species; geographic distribution; comments). - Dagosta et al., 2014: 373 (comparative material). - Carvalho et al., 2014: 248 (diagnosis of H. flammeus). - Lima et al., 2014: 170 (diagnosis of H. montagi). - Vieira et al., 2016: 57- 60 (description of pelvic- and anal-fins bony hooks; examined material). Hyphessobrycon cf. itaparicensis. - Costa, 2004: 6 (habitat notes). Hyphessobrycon ellisae Bragança, Ottoni & Rangel-Pereira, 2015: 256 (original description, type locality: Brazil, Sergipe State, Município de Estância, about 8 km north of Santa Cruz do Abais). Preoccupied by H. ellisae (Pearson, 1924) and replaced by Hyphessobrycon sergipanus (Bragança et al., 2016). Hyphessobrycon sergipanus Bragança, Ottoni & Rangel- Pereira, 2016: 373 (name replacement for H. ellisae). NEW SYNONYM. Diagnosis. Hyphessobrycon itaparicensis can be easily distinguished from most congeners, except the species of the “rosy tetra clade” sensu Weitzman, Palmer (1997), and H. balbus Myers, H. bifasciatus Ellis, H. chocoensis García- Alzate, Román-Valencia & Taphorn, H. columbianus Zarske & Géry, H. eilyos Lima & Moreira, H. flammeus Myers, H. gracilior Géry, H. griemi Hoedeman, H. igneus Miquelarena, Menni, López & Casciotta, H. panamensis Durbin, H. savagei Bussing, H. scutulatus Lucena, H. sebastiani García-Alzate, Román-Valencia & Taphorn, H. taguae García-Alzate, Román-Valencia & Taphorn, H. tortuguerae Böhlke, and H. weitzmanorum Lima & Moreira, by the absence of any concentration of dark chromatophores at the caudal-peduncle region (vs. presence of a dark blotch or a longitudinal dark stripe extending over the caudal-peduncle region). Among the “rosy tetra clade”, H. itaparicensis differs from H. axelrodi (Travassos), H. bentosi Durbin, H. compressus (Meek), H. copelandi Durbin, H. dorsalis Zarske, H. epicharis Weitzman & Palmer, H. eques (Steindachner), H. erythrostigma (Fowler), H. georgettae Géry, H. haraldschultzi Travassos, H. heteresthes Ulrey, H. jackrobertsi Zarske, H. khardinae Zarske, H. megalopterus (Eigenmann), H. micropterus (Eigenmann), H. minor Durbin, H. pando Hein, H. pyrrhonotus Burgess, H. rosaceus Durbin, H. roseus (Géry), H. simulatus (Géry), H. socolofi Weitzman, H. sweglesi (Géry), and H. takasei Géry by the absence of a black dorsalfin blotch (vs. presence). The species can be diagnosed from H. bifasciatus, H. flammeus, H. griemi, H. savagei, H. sebastiani, H. tortuguerae, and H. weitzmanorum by the absence of a conspicuous second humeral blotch, having instead an inconspicuous concentration of melanophores without defined limits, that initiates immediately posterior to a clear area on the rear of the first humeral blotch and fades posteriorly (vs. second humeral blotch as conspicuous as first humeral blotch). The species can be further distinguished from some aforementioned species by presence of 3-11 maxillary teeth (vs. 1-2 in H. bifasciatus, H. balbus, H. igneus, and H. ecuadoriensis, and 2 in H. chocoensis and H. sebastiani), 5-8 pored scales on lateral line (vs. 9-13 in H. columbianus, and 10-13 in H. savagei), presence of humeral blotch (vs. absence in H. eilyos, H. gracilior, and H. scutulatus), caudal fin hyaline (vs. caudal fin with black median stripe in H. weitzmanorum), 32-36 longitudinal scales series and vertically elongated humeral blotch (vs. 29-31 longitudinal scales series and rounded humeral blotch in H. taguae), and maxillary teeth tricuspid (vs. pentacuspid teeth in H. panamensis). When alive, H. itaparicensis can be diagnosed from most congeners by usually having yellowish body and fins, allied to a dark brown or reddish midlateral stripe extending from dorsalfin base to caudal peduncle. Description. Morphometric data are summarized in Tab. 1. Body somewhat compressed and elongate. Greatest body depth at vertical through dorsal-fin origin or slightly ahead of this point. Dorsal profile of head somewhat convex from upper lip to vertical through anterior nostrils; straight to slightly convex above eye and somewhat concave from the vertical through posterior border of eye and to tip of supraoccipital spine. Dorsal profile of body somewhat convex from tip of occipital spine to dorsal-fin origin; straight to somewhat convex and posteroventrally slanted along dorsal-fin base; straight from end of dorsal-fin base to adipose fin and slightly concave along caudal peduncle. Head rounded anteriorly in lateral profile. Ventral profile of head and body convex from lower lip to pelvic-fin origin; straight from that point to anal-fin origin; straight and posterodorsally slanted along anal-fin base, and slightly concave along ventral profile of caudal peduncle. Eyes relatively large compared with head length. Lower jaw slightly longer than upper jaw, mouth terminal. Posterior terminus of maxilla usually extending beyond vertical through anterior margin of orbit. Nostrils close to each other and separated by skin flap; anterior opening small, semicircular and with dermal flap; posterior one more than twice in size, elongate and without dermal flap. Nasal bone present. Frontals separated anteriorly, with wide fontanel; parietal fontanel large, extending from epiphyseal bar to supraoccipital spine, slightly narrowed anteriorly. Infraorbital series variable; usually six elements but only five elements are present in some specimens, possibly due to fusion of infraorbitals three with four (e.g., UFBA 7553, 27.4 mm SL). Third infraorbital largest and contacting laterosensory canal of preopercle ventrolaterally. Laterosensorial canal of first infraorbital absent; canal present and close to inner margin of orbital rim from second to fourth infraorbitals. Degree of development of the parietal branch of the supraorbital canal variable, reaching parietal bone (UFBA 7558), just reaching suture between frontal and parietal bones (CIUFS 426, 38.9 mm SL; UFBA 7553, 27.4 mm SL), or poorly developed, not reaching the suture between frontal and parietal bones (CIUFS 694, 21.9 mm SL; UFBA 7515, 19.0 mm SL). Premaxillary teeth in two rows; outer row with one (2), two* (46) or three (52) teeth bearing three cusps; inner row with four (1), five* (74), six (24), or seven (1) teeth bearing three to five cusps; symphyseal tooth of inner series narrow, asymmetrical, usually without cusp on anteromedial side, one larger central cusp and one smaller on lateral side; second or third tooth the largest, with three or five cusps; last teeth smaller with three cusps or conical. Maxilla with three* (11), four (25), five (16), six (26), seven (12), eight (2), nine (4), or 11(1) teeth; anterior ones usually with three cups and posterior ones conical. Dentary with 11(1), 12(5), 14(2), 15(2), 16(1), or 19(1) teeth; four or five large anterior teeth cusps with three in most specimens examined, but specimens around 37.0 mm SL or larger with anterior teeth pentacuspid; seven to 14 smaller posterior teeth, usually conical (Fig. 2). Scales cycloid, circuli absent on exposed area of scales, with several parallel radii extending to posterior margin of scale. Lateral line incomplete; with five (3), six* (38), seven (42), or eight (10) pored scales; longitudinal scales series including pored scales 32(1), 33(10), 34(22), 35(19), or 36(3). Some scales lost in the holotype. Horizontal scale rows between dorsal-fin origin and pelvic-fin insertion 12*(14) or 13(78), commonly six above and six below lateral line, and more rarely seven above and six below. Scales along middorsal line between tip of supraoccipital process and origin of dorsal fin 10*(36), 11(35), or 12(9). Horizontal scale rows around caudal peduncle 13*(5) or 14(53). Base of anteriormost anal-fin rays covered by a series of three to five scales. Caudal fin with scales restricted to the base of rays. Muscular reduction at vertical through anterior portion of the swimbladder; swimbladder not completely exposed but covered by a thin layer of musculature; muscular reduction between first and second pleural ribs, visible or not by transparency through the body wall as a deep dark area under the humeral blotch. Dorsal-fin rays ii,8(3), ii,8,i(6), ii,9*(82), iii,9(4), ii,10(7). Distal margin of dorsal fin straight or slightly rounded. Dorsal-fin origin situated at vertical through approximately middle of standard length. Base of last dorsal-fin ray anterior to vertical through anal-fin origin. First dorsal-fin pterygiophore inserting behind neural spine of 10 th (8) vertebra. Adipose fin present. Anal-fin rays unbranched rays iii*(24), iv(70) or v(1); branched rays 20(2), 21(19), 22(24), 23*(28), 24(17), 25(7), or 26(1). Distal margin of anal fin slightly concave. First anal-fin pterygiophore inserting behind haemal spine of 15 th (4) or 16 th (4) vertebra. Pectoral-fin rays i,9(11), i,9,ii(3), i,10(46), i,10,i(1), i,11*(36), or i,12(5). Tip of pectoral fin usually reaching or slightly surpassing vertical through pelvic-fin insertion. Pelvic-fin rays i,5(1), i,6*(102), or i,7(2); tip of pelvic fin of mature males usually extends beyond insertion of first anal-fin ray. Caudal fin forked, lobes pointed, similar in size. Principal caudal-fin rays i,9+8,i(11). Eight (4), nine (4), 10(1), or 11(1) dorsal procurrent caudal-fin rays, and eight (7) or nine (3) ventral procurrent caudal-fin rays. First gill arch with five (4), six (3), or seven (1) gill rakers on epibranchial, eight (2) or nine (6) on hypobranchial and ceratobranchial, and one (8) on cartilage between ceratobranchial and epibranchial. Precaudal vertebrae 13(2), 14(7), or 15(2) and caudal vertebrae 19(1), 20(6), 21(3), or 22(1); total vertebrae 33(1), 34(8), 35(1), or 37(1). Supraneurals four (2), five (6), or six (2). Branchiostegal rays four (11). Coloration in alcohol. Overall ground color yellow to light brown (Fig. 1). Guanine restricted to part of infraorbitals, preopercle, and opercle in somewhat recently fixed specimens. Dorsal part of head with melanophores sparsely and evenly distributed, usually darker posterior to eyes. Melanophores sparsely distributed over maxilla and lateral portion of head, larger posterior to eyes. Opercle with sparse melanophores, usually more concentrated on its dorsal half. Ventral portion of head with a few scattered small melanophores, more concentrated on anteriormost portion. Dorsum and scales along lateral of body with sparse melanophores; middorsal series usually homogeneously darkened; two or three dorsalmost series of scales with clearer posterior border. Scales below it with melanophores homogeneously distributed. Abdominal region clear or with sparse tiny melanophores. Humeral region with a vertically-elongated faint humeral blotch, wider dorsally and tapering ventrally; widest portion located on second horizontal series above lateral line, reaching three or four scales horizontally. Humeral blotch preceded and followed by clear areas, although clear areas not completely devoid of melanophores; blotch formed by superficial melanophores. Some specimens, usually about 33.0 mm SL or larger, with concentration of melanophores posterior to the clear area on the rear of the humeral blotch, but not characterizing a well-defined second blotch (see item Discussion). Midlateral black narrow stripe along horizontal septum from vertical through dorsal-fin origin to caudal peduncle, more evident in the stretch posterior to the dorsal-fin origin, but falling short of the end of caudal peduncle; dark line or stripe formed by melanophores over skin and also embedded dark pigmentation; largest specimens (about 37.0 mm SL or larger) with longitudinal stripe slightly wider and less conspicuous. No distinct caudal-peduncle blotch or/and stripe. All fins slightly darkened; dorsal, caudal, and pectoral usually with tiny melanophores forming dark lines along borders of rays and sparse melanophores on interradial membranes. Anal fin similarly colored, but lacking dark lines on borders of rays; distal border of fin somewhat darker, more evident on anteriormost rays. Pelvic fin somewhat less colored, with melanophores usually restricted to distal portion of rays; some specimens with distal half of rays distinctly dark. Adipose fin mostly hyaline; some specimens with few scattered small melanophores at base of fin. Specimens sampled in black water streams usually with overall darker coloration of body and fins, rendering some patterns and blotches described above somewhat merged with ground coloration and inconspicuous. Coloration in life. Life color pattern is somewhat variable along distribution and apparently influenced by the physical characteristics of water body inhabited by each population (Fig. 3). Specimens from clear water rivers usually possess yellowish overall body coloration, including distinct yellow coloration of fins, maxillae, and dorsal half of head (Figs. 3a, c-e). Additionally, a brown-reddish longitudinal stripe, from the rear of the humeral blotch or body midlength to the caudal peduncle is observed in some of those specimens (Fig. 3d). On the other hand, specimens from dark waters are more pigmented, with no humeral blotch or clear surrounding areas visible (Fig. 3b). These specimens are usually shiny silver, with large amount of guanine over scales on flank and dark longitudinal stripe, when visible. They possess yellow or orange chromatophores over scales on anterior half of body and strong yellow to orange fins. Sexual dimorphism. Lima, Costa (2001: 235) mentioned “no hooks on fins” of H. itaparicensis. However, Brito et al. (2014) and Vieira et al. (2016) recently reported the presence of bony processes on anal and pelvic fins in H. itaparicensis specimens from rivers draining Sergipe State. Examination of paratypes of H. itaparicensis (MZUSP 57540, UFRJ 4843) and various recently sampled specimens also revealed well-developed bony processes on first to fourth branched anal-fin rays and on the anteriormost two or three branched pelvic-fin rays (Fig. 4). Anal-fin bifurcated bony processes are distributed from the last unbranched up to the eighth branched anal-fin rays, usually on distal half of rays, on the segment just before the bifurcation of rays and continuing on dorsal hemitrichium of each ray. Bony processes are concave, anterodorsally directed bilaterally, symmetric, larger around midlength of branched portion of rays (Fig. 4a), and usually more numerous in the third and fourth branched anal-fin rays, with up to 12 paired processes (UFBA 7558, 40.5 mm SL). Pelvic-fin rays have similar concave and anterodorsally directed bony processes on the first and second, rarely on third, branched rays of mature males (Fig. 4b; see also Brito et al. (2014: 1159, Fig. 5d). However, pelvic-fin bony processes are not bifurcate and are distributed on the border of three or four segments anterior to branching point or restricted to the dorsal hemitrichium. Bony processes decrease in size on distal portion of rays. Up to 15 bony processes were observed in the first and 13 processes on the second branched ray (UFBA 7558, 40.5 mm SL). In one paratype (MZUSP 57540, 25.4 mm SL), six processes were observed in each of the two first branched rays and in another paratype (UFRJ 4843, 32.0 mm SL), processes occur on three first branched rays. Other sexually dimorphic traits observed in H. itaparicensis include interradial membrane on areas with bony processes on both fins tumescent, shape of the analfin profile distinct in males and females, and pelvic-fin length distinct in males and females. According to Brito et al. (2014: 1159, Figs. 5 a-b) the anal-fin distal profile is almost straight in males vs. concave from fifth to tenth branched ray in females. Examination of mature males performed herein corroborates this information, although with some variation among populations examined. Brito et al. (2014) described the distal end of the pelvic fin surpassing the anal-fin origin in males but not reaching the anal fin in females. However, examination of paratypes (UFRJ 4843, 32.0) revealed pelvic fin of females reaching the anal-fin origin and non-type mature males with pelvic fin barely reaching anal-fin base (UFBA 7558, 40.5 mm SL). Males usually have tips of pelvic-fin rays reaching beyond the anal-fin origin and overlapping the base of the first branched fin rays, while in females the pelvic fin may reach the anal fin but does not reach the basal portion of the branched fin rays. The holotype is apparently a female, relatively large-sized, without bony processes on fin rays, with concave anal-fin profile, and pectoral-fin barely reaching pelvic-fin insertion. Distinct elongation of fins in males and sexually dimorphic coloration typical of various species of Hyphessobrycon were not observed in H. itaparicensis. Gill glands (Burns, Weitzman, 1996) were not found on first gill arch of neither sex. Geographic distribution. Hyphessobrycon itaparicensis occurs in small coastal Brazilian rivers in the Northeastern Mata Atlântica freshwater ecoregion (NMAF), from streams around Camamu municipality, Bahia State in its southernmost distribution, to tributaries of rio Sergipe in Areia Branca municipality, Sergipe State, up north (Fig. 5). The known distribution of this species is restricted to a group of basins proposed by Camelier, Zanata (2014), the ‘Group North’, which includes drainages situated in the northernmost portion of the NMAF ecoregion. Ecological notes. Hyphessobrycon itaparicensis was first sampled in a small clear water stream (about 4 m wide and 1 m deep) below a small waterfall in Ilha de Itaparica, located about 200 m from the sea, although without tidal influence (Lima, Costa, 2001), in Barra do Gil, municipality of Vera Cruz (C. Sampaio, person. comun.), on the eastern portion of the island. According to |
