Corydoras hephaestus

materials_examined

Paratype: 1 lot, 1 specimen — NUP 18142, 1, 27.8 mm SL: Brazil, Rondônia, Vilhena, tributary of Igarapé Piracolina, upper Rio Machado, Rio Madeira basin, near the road BR- 364, 12 ° 48 ’ 56 ” S, 60 ° 06 ’ 37 ” W, W. M. Ohara & P. L. Cunha, 3 Sep 2014.

Catalog of type specimens of the fish collection of the Núcleo de Pesquisas em Limnologia, Ictiologia e Aquicultura (NUP), Universidade Estadual de Maringá Paraná, Brazil

description

Description. Morphometric data presented in Table 1. Head compressed with convex dorsal profile; triangular in dorsal view. Snout moderately developed and pointed. Head profile slightly convex from tip of snout to anterior nares; ascending slightly convex or nearly straight from this point to posterior tip of parieto-supraoccipital process; slightly convex from that point to dorsal-fin origin; region between eye and posterior tip of parieto-supraoccipital slightly concave in specimens with more than 27.0 mm SL. Profile slightly convex along dorsal-fin base. Dorsal body profile posterior to dorsal fin slightly concave to adipose-fin spine; concave from that point to caudal-fin base. Ventral profile of body slightly convex from isthmus to pelvic-fin origin; nearly straight from that point to anal-fin origin; concave to caudal-fin base. Body roughly elliptical in cross section at pectoral girdle, gradually becoming more compressed toward caudal fin. Eye rounded, located dorsolaterally on head; orbit delimited dorsally by lateral ethmoid, frontal and sphenotic, ventrally by infraorbitals. Anterior and posterior nares close to each other, only separated by skin flap. Anterior naris tubu

Wrapped in flames: Corydoras hephaestus, a new remarkably colored species from the Rio Madeira basin (Teleostei: Callichthyidae)

diagnosis

Diagnosis. Corydoras hephaestus can be distinguished from all its congeners, with exception of C. difluviatilis Britto & Castro, 2002, C. flaveolus Ihering, 1911, C. gladysae, C. gracilis, C. hastatus Eigenmann & Eigenmann, 1888, C. latus, C. micracanthus, C. nanus, C. petracinii, C. pygmaeus Knaack, 1966, and C. undulatus Regan, 1912, by the absence of contact between the posterior process of the parieto-supraoccipital and the nuchal plate (vs. bones in contact). The new species can be distinguished from C. gladysae, C. gracilis, C. hastatus, C. latus, C. micracanthus, C. nanus, C. petracinii, C. pygmaeus and C. undulatus by having a ventral laminar expansion of infraorbital 1 conspicuously well-developed (vs. poorly to moderately developed); from C. difluviatilis and C. flaveolus by having a posterior margin of the pectoral-fin spine with serrations along almost its entire length, only absent on distal portion (vs. serrations, when present, restricted to the proximal portion of the spine).

Wrapped in flames: Corydoras hephaestus, a new remarkably colored species from the Rio Madeira basin (Teleostei: Callichthyidae)

distribution

Distribution. The new species is only known from its type locality, Igarapé Piracolina, a tributary of the upper Rio Machado, Rio Madeira basin, about 9 km south of Vilhena, near the border of Rondônia and Mato Grosso States, Brazil (Fig. 7). Ecological notes. The type locality of Corydoras hephaestus is located 585 m above sea level on the Chapada dos Parecis. It is a small terra-firme igarapé (= highland creek) with little preserved riparian vegetation and surrounded by large plantation fields (mostly soy and corn), near Vilhena, Mato Grosso. It is a clear water stream 1.5 ‒ 2.5 m wide and 0.3 ‒ 0.8 m deep, with swift currents, and a bottom composed of sand and dead leaves (Fig. 8). The new species are not abundant, and specimens were collected one by one. Shoalling behavior was not observed. Syntopic species included Ancistrus verecundus Fisch-Muller, Cardoso, da Silva & Bertaco, 2005, Bryconops piracolina Wingert & Malabarba, 2011, Cetopsorhamdia sp. 3 (cf. Bockmann & Slobodian, 2013: 25), Hyphessobrycon lucenorum Ohara & Lima, 2015, Hyphessobrycon aff. melonostichos Carvalho & Bertaco, 2006, Moenkhausia parecis Ohara & Marinho, 2016 and Pyrrhulina sp. The analysis of stomach c

Wrapped in flames: Corydoras hephaestus, a new remarkably colored species from the Rio Madeira basin (Teleostei: Callichthyidae)