Bryconops tocantinensis

conservation

Conservation status. Considering that, although its known geographic distribution is restricted, current relevant threats to the species were not detected in its distribution area, Bryconops tocantinensis could be classified as Least Concern (LC), according to the International Union for Conservation of Nature (IUCN) categories and criteria (IUCN Standards and Petitions Subcommittee, 2016). Further studies on biology, ecology and distribution of the species could detect plausible threats to the population of Bryconops tocantinensis, perhaps leading to a revaluation of the conservation status of the species.

A new species of Bryconops (Ostariophysi: Characiformes: Characidae) from the upper rio Tocantins drainage, Brazil

description

Description. Morphometric data presented in Table 1. Moderate to small-sized species of Bryconops, largest specimen examined 65.0 mm SL. Elongate body, laterally compressed. Greatest body depth at dorsal-fin origin. Dorsal body profile convex from snout to vertical through anterior nostrils; straight or slightly convex from posterior nostrils to tip of supraoccipital bone; convex from this point to dorsal-fin origin. Straight and posteroventrallyaligned along dorsal-fin base; postdorsal profile straight from base of last dorsal-fin ray to adipose-fin origin and concave from latter point to end of caudal peduncle. Ventral profile convex from snout to pelvic-fin insertion; straight or slightly convex from this point to anal-fin origin; straight and posterodorsally-aligned along anal-fin base; postventral profile concave from base of last anal-fin ray to end of caudal peduncle. Head large. Posterior margin of opercle slightly sinusoidal. Mouth terminal. Premaxilla and dentary positioned at same level, or premaxilla slightly longer than dentary. Snout shorter than eye diameter. Eyes large. Adipose ocular membrane well-developed. Maxilla moderately enlarged, its distal portion not reach

A new species of Bryconops (Ostariophysi: Characiformes: Characidae) from the upper rio Tocantins drainage, Brazil

description

u r n: lsid: zooba n k. org: a ct: DA 0 E 050 F-E 8 A A- 414 A- 9 BCE - 1 A 08 BA 312 B 55 Figs. 1 - 4

A new species of Bryconops (Ostariophysi: Characiformes: Characidae) from the upper rio Tocantins drainage, Brazil

diagnosis

Diagnosis. Bryconops tocantinensis is distinguished from all species of genus Bryconops, except B. humeralis Machado-Allison, Chernoff & Buckup and B. vibex Machado-Allison, Chernoff & Buckup by the color pattern in vivo (dorsal, adipose, and caudal fins entirely orange). Bryconops tocantinensis is easily distinguished from B. humeralis and B. vibex by the absence of humeral spot and by the lack of maxillary teeth (vs. presence of a single humeral spot and presence of 1 - 3 maxillary teeth on both sides). Furthermore, B. tocantinensis is distinguished from B. inpai Knöppel, Junk & Géry, and B. munduruku Silva-Oliveira, Canto & Ribeiro by the absence of humeral spot (vs. two spots). Bryconops tocantinensis is distinguished from B. disruptus Machado-Allison & Chernoff, B. durbini (Eigenmann), B. piracolina Wingert & Malabarba, B. giacopinii (Fernández-Yépez), B. magoi Chernoff & Machado-Allison, B. collettei Chernoff & Machado-Allison, B. vibex, B. transitoria (Steindachner), B. gracilis (Eigenmann), and B. alburnoides Kner by the number of perforated lateral line scales (38 - 41 vs. 9 - 23, 30, 31 - 36, 43 - 46, 43 - 47, 43 - 48, 44 - 46, 45 - 46, 54, and 57 - 61 perforated lateral

A new species of Bryconops (Ostariophysi: Characiformes: Characidae) from the upper rio Tocantins drainage, Brazil