Bryconops Munduruku (Characiformes: Characidae), a New Species of Fish from the Lower Tapajós River Basin, Brazil
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Zootaxa 3994 (1): 133–141 ISSN 1175-5326 (print edition) www.mapress.com/zootaxa/ Article ZOOTAXA Copyright © 2015 Magnolia Press ISSN 1175-5334 (online edition) http://dx.doi.org/10.11646/zootaxa.3994.1.7 http://zoobank.org/urn:lsid:zoobank.org:pub:D9D78466-2E20-4BAA-8520-E0F2FBBDDB1D Bryconops munduruku (Characiformes: Characidae), a new species of fish from the lower Tapajós River basin, Brazil CÁRLISON SILVA-OLIVEIRA1, ANDRÉ LUIZ C. CANTO2 & FRANK RAYNNER V. RIBEIRO1,2 1Programa de Pós-Graduação em Recursos Aquáticos Continentais Amazônicos, Instituto de Ciências e Tecnologia das Águas, Uni- versidade Federal do Oeste do Pará. Rua Vera Paz, s/n – Sal, CEP 68035-110, Santarém, Pará, Brazil. E-mail: [email protected]; [email protected] 2Coleção Ictiológica da Universidade Federal do Oeste do Pará. Campus Amazônia. Avenida Mendonça Furtado, 2.946 - Fátima, CEP 68040-470, Santarém, Pará, Brazil. E-mail: [email protected] Abstract A new species of Bryconops is described from a right tributary of the lower Tapajós River, State of Pará, Brazil. Bryconops munduruku, sp. nov., differs from its congeners, except B. inpai and B. piracolina, by having a black adipose fin (vs. ad- ipose fin hyaline in alcohol) and, except B. inpai, by possessing two humeral blotches (vs. lack of humeral blotch or only one humeral blotch). Bryconops munduruku differs from B. inpai by having a uniform color pattern on the posterior por- tion of the side of the body (vs. a dark stripe extending posteriorly from the half of the anal-fin base onto the base of the middle caudal-fin rays). It differs further from B. inpai and B. piracolina by the presence of a black adipose fin that is hyaline along its base (vs. entirely black adipose fin in B. inpai and B. piracolina). The new species is allocated in the subgenus Creatochanes by having a maxillary bone with one to three teeth on both sides, and its posterior extension reach- ing the junction of second and third infraorbital bones. Key words: subgenus Creatochanes, taxonomy, Tapajós National Forest, Amazon basin Resumo Uma espécie nova de Bryconops descrita de um afluente da margem direita do baixo rio Tapajós, Pará, Brasil. Bryconops munduruku difere de seus congêneres, exceto B. inpai e B. piracolina, pela nadadeira adiposa preta (vs. nadadeira adiposa hialina em álcool) e, exceto B. inpai, por apresentar duas manchas umerais. Bryconops munduruku difere de B. inpai pelo padrão uniforme de coloração na porção posterior do corpo (vs. uma faixa lateral escura que se estende posteriormente da metade da base da nadadeira anal at a base dos raios medianos da nadadeira caudal). Difere ainda de B. inpai e B. piraco- lina pela nadadeira adiposa escura distalmente, mas hialina ao longo de sua base (vs. nadadeira adiposa completamente escura em B. piracolina e B. inpai). A espécie nova alocada no subgênero Creatochanes por apresentar de um a três dentes em cada osso maxilar e a margem posterior da maxila alcançando a margem posterior do segundo infraorbital. Introduction Bryconops was proposed by Kner (1858) to allocate two new species, Bryconops alburnoides Kner and Bryconops lucidus Kner (= Bryconops alburnoides Kner), described based on specimens from the Guaporé and Branco rivers, Brazil, respectively. Currently 19 valid species are recognized in the genus (Lima et al. 2003; Chernoff & Machado-Allison 2005; Wingert & Malabarba 2011; Eschmeyer 2015). The genus is restricted to freshwater drainages of South America, occurring in the Amazon, Orinoco, Tocantins, São Francisco, and Paraguay river basins, and in coastal rivers of northern Brazil and the Guianas (Lima et al. 2003; Lima & Caires 2011; Polaz et al. 2014; Ramos et al. 2014; Eschmeyer 2015). Chernoff & Machado-Allison (1999, 2005) divided the species of Bryconops into two subgenera, Bryconops and Creatochanes Günther 1864, based on the number of maxillary teeth and position of the posterior margin of the maxillary bone in relation to the contact between the second and third infraorbital bones. Accepted by M.R. de Carvalho: 18 May 2015; published: 30 Jul. 2015 133 Among the valid species, eight exhibit characters proposed for the subgenus Bryconops: B. alburnoides, B. caudomaculatus (Günther 1864), B. collettei Chernoff & Machado-Allison 2005, B. disruptus Machado-Allison & Chernoff 1997, B. durbini (Eigenmann 1908), B. gracilis (Eigenmann 1908), B. magoi Chernoff & Machado- Allison 2005, and B. piracolina Wingert & Malabarba 2011. Eleven species exhibit characters proposed for the subgenus Creatochanes: B. affinis (Günther 1864), B. colanegra Chernoff & Machado-Allison 1999, B. colaroja Chernoff & Machado-Allison 1999, B. cyrtogaster (Norman 1926), B. giacopinii (Fernández-Yépez 1950), B. humeralis Machado-Allison, Chernoff & Buckup 1996, B. imitator Chernoff & Machado-Allison 2002, B. inpai Knöppel, Junk & Géry 1968, B. melanurus (Bloch 1794), B. transitoria Steindachner 1915, and B. vibex Machado- Allison, Chernoff & Buckup 1996. In this paper, a new species of Bryconops is described from the igarapé Açu, a tributary of the lower Tapajós River basin in Brazil. Material and methods Methods for taking morphometric and meristic data followed Fink & Weitzman (1974) and Machado-Allison et al. (1993, 1996), except for counts of horizontal scale rows below the lateral line that were taken following Malabarba & Bertaco (1999). All measurements were taken point to point, on the left side of the body, with digital caliper to the nearest 0.1 mm, and are summarized in the species accounts and table as percentages of Standard Length (SL) or Head Length (HL). Drawings and counts of vertebrae, supraneurals, pterygiophores, procurrent caudal-fin rays, gill rakers on the first branchial arch, and branchiostegal rays were taken from cleared and stained (c&s) paratypes, prepared following the clearing and staining methods of Taylor & van Dyke (1985). Institutional abbreviations follow Ferraris Jr. (2007), with the addition of the Fish Collection of Universidade Federal do Oeste do Pará (UFOPA-I). Comparisons to species not listed in comparative material were based on the literature. In the description, counts are followed by number of frequencies, corresponding to the number of specimens analyzed; asterisk within parentheses (*) indicates the holotype count. In the list of comparative material examined, museum abbreviations and catalog numbers are followed by the total number of specimens in that lot, range of standard length, and collecting data. Bryconops munduruku, new species (Figures 1–3; Table 1) Holotype. INPA 46510, male, 76.6 mm SL, Brazil, Pará State, Aveiro, igarapé Açu, tributary of the right margin of the Tapajós River, about 10 km of the city of Aveiro, 0336’0.99’’S 5514’59.14’’W, 23 May 2013, C. Silva-Oliveira & S. R. Oliveira. Paratypes. All collected with holotype, Brazil, Pará State, Tapajós River basin: MCP 48315 (5, 34.0–79.6 mm SL); INPA 46511 (11, 33.5–91.7 mm SL; 2 c&s, 31.8–74.1 mm SL); UFOPA-I-00655 (7, 33.4–96.4 mm SL; 5 c&s, 47.6–63.3 mm SL). Diagnosis. Bryconops munduruku differs from its congeners, except B. inpai and B. piracolina, by possessing a black adipose fin (vs. adipose fin hyaline in alcohol). It differs from B. inpai and B. piracolina by possessing a hyaline band on the black adipose-fin base (vs. entirely black adipose fin in B. piracolina and B. inpai). Bryconops munduruku differs further from B. piracolina by having a hyaline dorsal fin (vs. presence of a large black blotch on the dorsal-fin base). Bryconops munduruku differs from other species of the subgenus Creatochanes, except B. inpai, by possessing two humeral blotches (vs. lack of humeral blotch or humeral region with a single humeral blotch in B. humeralis and B. vibex). It differs further from B. inpai due to the uniform color pattern on the posterior portion of the side of the body (vs. presence of a dark stripe extending posteriorly from the half of the anal-fin base onto the base of the middle caudal-fin rays). Description. Morphometric data presented in Table 1. Body shape compressed, greatest body depth located just anterior to dorsal-fin origin. Dorsal profile of body slightly convex from snout tip to dorsal-fin origin; straight to slightly concave from dorsal insertion to adipose-fin origin, gently sloping to beginning of caudal peduncle. 134 · Zootaxa 3994 (1) © 2015 Magnolia Press SILVA-OLIVEIRA ET AL. Caudal peduncle concave along dorsal and ventral margins. Ventral profile of head and body convex from lower lip to pelvic-fin origin, and straight from this point to anal-fin origin. Ventral profile straight and posterodorsally inclined along anal-fin base. TABLE 1. Morphometric data of holotype and 30 paratypes of Bryconops munduruku. Holotype is included in the ranges and means. SD = standard deviation. Holotype Range Mean SD Standard Length (mm) 76.6 31.8–96.4 61.4 - Percents of Standard Length Predorsal length 41.4 41.4–50.6 48.8 1.6 Preanal length 66.7 60.4–67.3 65.3 1.4 Prepelvic length 49.0 47.4–52.6 49.8 1.3 Prepectoral length 26.4 25.5–29.1 27.1 0.8 Dorsal-fin base length 13.1 9.8–17.9 14.5 1.4 Dorsal origin to pectoral origin 37.3 31.5–38.5 35.8 1.7 Dorsal origin to pelvic origin 33.7 27.1–35.3 31.9 2.0 Dorsal terminus to anal origin 35.1 27.6–37.8 34.1 2.5 Dorsal terminus to anal origin 28.1 21.5–30.8 27.4 2.2 Dorsal terminus to pelvic origin 33.4 27.7–35.4 32.1 1.9 Dorsal terminus to anal terminus 31.9 26.3–35.3 31.0 1.7 Dorsal terminus to adipose origin 22.1 21.3–26.6 22.9 1.1 Adipose terminus to hypural plate 14.6 11.7–16.0 14.4 1.1