Hyphessobrycon uaiso, Carvalho & Langeani, 2013

Carvalho, Fernando R. & Langeani, Francisco, 2013, Hyphessobrycon uaiso: new characid fish from the rio Grande, upper rio Paraná basin, Minas Gerais State (Ostariophysi: Characidae), with a brief comment about some types of Hyphessobrycon, Neotropical Ichthyology 11 (3), pp. 525-536 : 526-530

Hyphessobrycon uaiso , new species

Figs. 1-3

Holotype. DZSJRP 16460, 50.2 mm SL, Brazil, Minas Gerais, Ponte Alta District, municipality of Uberaba, headwaters of rio Uberaba , near BR-262 road, 19º40’58.7”S 47º40’7.3”W, 1020 m a.s.l., 8 Sep 2006, F. R. Carvalho, F. Langeani, H. F. Chaves, F. O. Martins & C. P. Ferreira.

Paratypes. DZSJRP 8731, 272, 17.6-47.4 mm SL, 3 c&s, 28.5- 49.8 mm SL; LIRP 9298 , 15 , 27.4-41.5 mm SL ; MCP 47520, 20 , 26.3-52.9 mm SL ; MZUSP 112117 , 20 , 26.7-46.1 mm SL ; UFRGS 17013 , 15 , 25.7-40.9 mm SL ; MNRJ 40368 , 20 , 27.1-46.6 mm SL ; MZUEL 6593 , 15 , 27.3-41.1 mm SL ; NUP 1090 , 15 , 24.9-45.8 mm SL ; INPA 38114 , 15 , 25.7-47.7 mm SL; same data as holotype ; DZSJRP 15804 , 105 , 25.7-43.6 mm SL, 3 c&s, 32.5-33.6 mm SL, 6 (ethyl alcohol anhydrous), 25.0- 32.3 mm SL, same locality as holotype, 11 Mar 2012, F . R. Carvalho, F. Langeani & F. O. Martins .

Diagnosis. The new species, Hyphessobrycon uaiso , promptly differs from most congeners [except H. amaronensis García- Alzate, Róman-Valencia & Prada-Pedredos, H. arianae Uj & Géry , H. balbus Myers , H. boulengeri (Eigenmann) , H. brumado Zanata & Camelier , H. coelestinus Myers , H. cyanotaenia Zarske & Géry , H. diancistrus Weitzman , H. duragenys Ellis , H. eilyos Lima & Moreira, H. elachys Weitzman , H. eos Durbin , H. frankei Zarske & Géry , H. hamatus Bertaco & Malabarba , H. isiri Almirón, Casciotta & Koerber , H. langeanii Lima & Moreira, H. mavro García- Alzate, Róman-Valencia & Prada-Pedredos, H. melanostichos Carvalho & Bertaco , H. metae Eigenmann & Henn , H. minimus Durbin , H. negodagua Lima & Gerhard, H. niger García- Alzate, Róman-Valencia & Prada-Pedredos, H. notidanos Carvalho & Bertaco , H. poecilioides Eigenmann , H. reticulatus Ellis , H. rutiliflavidus Carvalho, Langeani, Miyazawa & Troy , H. santae Eigemann , H. sovichthys Schultz , H. stegemanni Géry , H. taurocephalus Ellis , H. tenuis Géry , H. togoi Miquelarena & Lopez , H. tukunai Géry , H. vinaceus Bertaco, Malabarba & Dergam , and H. weitzmanorum Lima & Moreira] by the short anal fin with 12-17 branched rays (mode 14) [vs. less than 11 in H. albolineatum Fernandez-Yépez and more than 18 on the remaining species], and dorsal fin with ii,7-8 rays [except H. arianae Uj & Géry , H. guarani Mahnert & Géry , H. otrynus Benine & Lopes , H. procerus Mahnert & Géry , H. stramineus Durbin , and H. wajat Almirón & Casciotta ] (vs. dorsal fin ii,8,i, ii,9, ii,10, iii,8, iii,9, or iv,9 rays on the remaining species). From these species with the same range of branched anal-fin and dorsal-fin rays, Hyphessobrycon uaiso differs by the presence of i,5-6 rays on the pelvic-fin (vs. i, 7 in H. amaronensis , H. arianae , H. boulengeri , H. balbus , H. diancistrus , H. duragenys , H. eos , H. hamatus , H. langeanii , H. mavro , H. melanostichos , H. minimus , H. niger , H. otrynus , H. poecilioides , H. reticulatus , H. santae , H. sovichthys , H. stegemanni , H. tenuis , H. togoi , and H. vinaceus ), a conspicuous black humeral spot (vs. humeral spot absent, faint or barely discernible in H. brumado , H. eilyos , H. elachys , H. guarani , H. procerus , H. stramineus , H. tukunai , and H. wajat ), one or rarely two maxillary teeth with up to seven cusps (vs. two or more maxillary teeth with up to six cusps in H. coelestinus , H. metae , H. notidanos - which can also have up to seven cusps, but never only one teeth in the maxillary, and H. rutiliflavidus ), and adipose fin present (vs. adipose fin absent in H. negodagua and H. taurocephalus ). Furthermore, Hyphessobrycon uaiso can be distinguished from the congeners by the color pattern of the eyes in life, slightly blue on the lower half and blackish on the upper half, on males and females.

Description. Morphometric data are presented in Table 1. Body compressed, moderately short, greatest body depth at vertical through dorsal-fin origin or straightway after. Dorsal profile of head convex from tip of upper jaw to vertical through anterior nostril; slightly straight or concave from that point to tip of supraoccipital spine. Dorsal profile of body slightly convex from posterior tip of supraoccipital spine to base of last dorsal-fin ray, and straight to adipose-fin origin. Ventral profile of body convex from tip of lower jaw to pelvic-fin origin, straight or slightly convex from that point to anal-fin origin, and straight and/or subtly rounded along anal-fin base. Dorsal and ventral profile of caudal peduncle slightly straight.

Eyes moderate, without distinct adipose eyelid. Jaws equal in size, mouth terminal. Maxilla extending posteriorly surpassing anterior margin of orbit until vertical through crystalline lens anterior margin, slightly curved, aligned approximately at 45 degrees angle relative to longitudinal axis of body. Nostrils close to each other, anterior opening small and circular, posterior one twice in size and slightly reniform or elongate. Nostrils separated by skin flap. Frontals united anteriorly or not, with a triangle-shaped fontanel; parietal fontanel large, extending from epiphyseal bar to supraoccipital spine. Infraorbital series with five or six elements, fourth infraorbital reduced dorsally (triangle-shaped), rectangular, or fusioned with fifth infraorbital. Laterosensorial canal from first to sixth infraorbital close to inner margin of orbital rim. Third infraorbital largest, double size of others (in length and depth), contacting laterosensory canal of preopercle ventrolaterally.

Premaxillary teeth in two rows: outer row with 3(4) or 4*(48), tri- to pentacuspid teeth; inner row with 5*(53) penta- to heptacuspid teeth. Dentary with 5*(53) large, penta- to heptacuspid teeth, followed by a series of 4-6 (6) small teeth, conical or tricuspid, abruptly smaller than the anterior largest teeth. Dorsal border of maxilla relatively straight. Maxilla with 1*(48) or 2 (5) penta- to heptacuspid teeth along anteroventral margin ( Fig. 2 ). Central median cusp of all teeth longer than remaining lateral cusps; cusp tips slightly curved inwardly on dentary teeth, and outwardly on premaxillary teeth.

Scales cycloid, with few radii (3-6), relatively small; circuli marked anteriorly and marginally (dorsal and ventral). Lateral line incomplete, extending to vertical through pelvic fin; perforated scales of lateral line 9(15), 10(8), 11*(4), 12(9), 13(6), 14(4), 15(3), 16(1), or 17(3); longitudinal scales series including pored scales 33(8), 34(13), 35*(19), or 36(13); 6*(48) or 6.5(5) scales rows between dorsal-fin origin and lateral line; 5*(53) scale rows between lateral line and pelvic-fin origin. Predorsal scales 10(6), 11*(24), 12(18), or 13 (5). Scale sheath along anal-fin base 5(12), 6*(21), 7(11), 8(6), 9 (4), or 10(1) in a single row. Circumpeduncular scales 14(47) or 15(6). Axillary scale small or absent.

Dorsal-fin rays ii,7(3) or 8*(50); first unbranched ray approximately one-half of second one or shorter. Dorsal-fin origin at midbody or posterior to that point, at vertical through anterior third of pelvic fin base. Base of last dorsal-fin ray at vertical through distal tip of pelvic fin, anterior to origin of anal fin. Tip of longest ray of adpressed dorsal fin at vertical through base of first two branched anal-fin rays. First dorsalfin pterygiophore inserting between neural spine of 7 th and 8 th (6) precaudal vertebra. In some specimens, tips of fin rays deformed (e.g., slightly bent). Adipose fin present, sometimes reduced (just one paratype specimen with adipose fin absent). Pectoral fin with i,9(14), 10*(35), or 11(3) rays, not extending to pelvic fin origin. Pelvic fin with i,5(1) or 6*(52) rays. Pelvicfin origin located anterior or just anterior to vertical through dorsal-fin origin. Tip of longest ray never reaching anal-fin origin.Anal-fin rays iii, 12(2), 13(5), 14(18), 15*(17), 16(9), or 17(2). Anal fin of males and females without bony hooks. Caudal fin forked, lobes slightly rounded, similar in size, with i,8/8,i(3), i,9/7,i (1), i,9/8,i*(46), or i,10/8,i (1) rays. Caudal fin naked, scales restricted to its base. Dorsal procurrent caudalfin rays 10(2), 11(3), or 12(1), and ventral procurrent caudalfin rays 9(3), 10(1), 11(1), or 12(1).

Branchiostegal rays 4. First gill arch with 6 gill rakers on epibranchial, 1 between epibranchial and ceratobranchial, 7(2) or 8(4) on ceratobranchial, and 2(5) or 3(1) on hypobranchial. Precaudal vertebrae 16(1) or 17(5) and caudal vertebrae 17(3), 18(2), or 19(1). Supraneurals 5(2) or 6(4), filiform, some with dorsal portion expanded.

Color in alcohol. Overall body color yellowish to brownish. Body scales slightly reticulated, especially on anterior

portion of scales. Head dusky to dark brown dorsally. Region of infraorbitals and opercle with small chromatophores, scattered uniformly, except on upper and posterior region with more concentration of spots. Top of head, from lips to supraoccipital process blackish, with high concentration of chromatophores. Humeral spot conspicuous, origin just after opercular opening and extending through five or six transversal scale series, vertically elongated on young specimens (up to 34 mm SL) and approximately vertically rounded on adults (larger than 34 mm SL). When vertically rounded, spot extending through five or six horizontal scale series, above lateral line; on young specimens (up to 32.4 mm), humeral spot slender ventral to lateral line. Lateral side of body with scattered melanophores except at abdominal region. Longitudinal stripe dark, one or one-half scale wide, extending from vertical through middle of pectoral fin, passing through end of caudal peduncle end, extending onto proximal one-third of middle caudal-fin rays. Longitudinal stripe more conspicuous posterior to vertical through middle of dorsal-fin base. Caudal peduncle spot merged to longitudinal stripe. Fins darkish, with scattered melanophores on rays and interradial membrane.

Color in life. Overall body and head color pattern yellowish, slightly brown ( Fig. 3 ). Pattern of melanophores distribution on head, body and fins similar to that described for specimens in alcohol. Dorsal, caudal, pelvic, and pectoral fins with anterior portion yellowish and posterior reddish. Adipose fin yellowish. Longitudinal stripe more conspicuous along caudal peduncle. Color pattern of eyes composed by slightly blue coloration on lower half and blackish on upper half of iris, on males and females ( Fig. 3b ).

Sexual dimorphism. The mature males and females of Hyphessobrycon uaiso , confirmed by visual and histological analyses, do not present bony hooks on fins. No difference (morphological or color pattern) was found between males and females. Also, gill glands (Burns & Weitzman, 1996) were not found macroscopically on first gill arch on both sexes.

Distribution. Hyphessobrycon uaiso is known from rio Uberaba, rio Grande drainage, upper rio Paraná basin ( Fig. 4 ). The upper rio Paraná basin is a well sampled Neotropical basin ( Langeani et al., 2007), and even though the upper rio Paraná basin can be considered a well sampled hydrographic system, we are unable to locate any additional samples of the species in the fish collections that hold most material from this river system.

Etymology. The specific name, uaiso , of Portuguese “uai sô”, is a common colloquial interjection used by most people living in Minas Gerais State, Brazil, to express surprise, confirmation, awe, amazement, in special those from the “Triângulo Mineiro”, region where the new species was found.A name in apposition.

Ecological notes. The headwaters of rio Uberaba are a marshland mainly dominated by Cyperaceae , with some Poaceae , Nymphaeaceae , Melastomataceae , Asteraceae ,

and Pteridophyta. When the bottom is not disturbed, the water is clear ( Fig. 5 ). Hyphessobrycon uaiso was found living in schools, occasionally solitary, at average depth of one meter. Schools were mainly found in open areas, devoid of vegetation ( Cyperaceae , mainly). Stomach contents of three c&s specimens contained mostly aquatic insect (apparently Diptera larvae), followed by algae, vegetal matter, Acari, and Thecamoebina. More details about the site of collection of H. uaiso are given by Langeani et al. (2007: 120).

Conservation remarks. Recently, Villa-Verde et al. (2012) described Listrura costai and classified this species as vulnerable according to the IUCN categories and criteria for evaluation of threatened species (IUCN, 2001, 2011). Nowadays, it seems important, whenever possible, to evaluate the conservation status of newly described species right at their descriptions. For Hyphessobrycon uaiso , as L. costai , the extremely restricted distribution (until now the headwater of rio Uberaba), together with a specificity of habitat, relative proximity of human settlements, the use of surrounding land for agriculture, and human water consumption, defining potential threats to the species, allow to apply the criterion D2 (area of occupation less than 20 km ²) for the category Vulnerable (VU). Nevertheless, deficiency about population studies or geographical range reductions are not available for the species. Accordingly, it is preferable to consider H. uaiso as data deficient (DD) until more information about its biology and occurrence on the basin is available.

The establishment of conservation measures for the rio Uberaba headwaters is important to conserve its surprisingly diverse restricted ichthyofauna, which include, besides Hyphessobrycon uaiso , another three putative endemic, and so far undescribed taxa: a new Characidae related to Hasemania crenuchoides (of Langeani et al., 2007), a new Crenuchidae , and a possibly undescribed species of Rivulus (Rivulidae) .

Figures

Fig. 1. Hyphessobrycon uaiso, holotype, DZSJRP 16460, 50.2 mm SL, headwaters of rio Uberaba, near BR-262 road, PonteAlta District, municipality of Uberaba, Minas Gerais State, Brazil.

Fig. 2. Hyphessobrycon uaiso, paratype, DZSJRP 8731, 36.4 mm SL. Scanning electronic micrograph of lower and upper jaws in mesial view, left side: a. maxillary; b. maxillary tooth in detail; c. premaxillary, and d. dentary. Scale bars: (a-d) = 200 µm; b = 30 µm, and c = 100 µm.

Fig. 3. Hyphessobrycon uaiso: (a) paratype, DZSJRP 15804, specimen just after fixation, 39.3 mm SL, and (b) specimen in aquarium, ca. de 40.0 mm SL, showing life coloration, not preserved. Photo (b) by Angelo Manzotti.

Fig. 4. Distribution map of Hyphessobrycon uaiso (square) in rio Uberaba (detail), rio Grande drainage, upper rio Paraná basin, Brazil. Base map of South America prepared by Marilyn Weitzman.

Fig. 5. Type locality of Hyphessobrycon uaiso, Brazil, Minas Gerais State, headwaters of rio Uberaba, near BR-262 road.