Corydoras gryphus

materials_examined

Paratypes: 2 lots, 24 specimens — NUP 1572, 21, 21.9 – 35.0 mm SL; NUP 14676, 3 c & s, 27.7 – 32.4 mm SL: Brazil, Paraná, Foz do Iguaçu, rio Paraná (near Ponte da Amizade), approximately 25 ° 31 ’ S, 54 ° 38 ’ W, Biological team of the Universidade Estadual de Maringá, 15 Oct 1982.

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 in Table 1. Head compressed with slightly convex dorsal profile; triangular in dorsal view. Snout slightly pointed. Head profile convex from snout to tip of posterior process of parieto-supraoccipital. Profile slightly convex along dorsal-fin base. Body profile between dorsal fin and adipose-fin spine slightly concave; concave from that point to caudal-fin base. Ventral profile of body nearly straight from isthmus to pectoral girdle; slightly convex from that point to pelvic girdle. Profile nearly straight from pelvic girdle to base of first anal-fin ray; concave from that point to caudal-fin base. Body roughly elliptical in cross section at pectoral girdle, gradually becoming more compressed toward caudal fin. Eye rounded, located dorso-laterally on head; orbit delimited dorsally by frontal and sphenotic, ventrally by infraorbitals. Anterior and posterior nares close to each other, only separated by flap of skin. Anterior naris tubular. Posterior naris close to anterodorsal margin of orbit, separated from it by distance equal to diameter of naris. Mouth small, subterminal, width nearly equal to bony orbit diameter. Maxillary barbel moderate in size,

A new long-finned Corydoras Lacépède, 1803 (Siluriformes: Callichthyidae) from the lower rio Paraná basin, Brazil

diagnosis

Diagnosis. Corydoras gryphus is distinguished from its congeners by a conspicuously reduction on posterior laminar expansion of infraorbital 2, almost absent in some specimens (vs. infraorbital 2 with moderate- or well-developed posterior laminar expansion). The new species differs from its congeners, except C. longipinnis and C. tukano, by the presence of an uncommon sexual dimorphic condition, with the conspicuous elongation of the first and second branched dorsal-fin rays in males surpassing dorsal-fin spine distal tip, with size similar to the total length of the spine (vs. dorsal fin not sexually dimorphic with respect to its length; or elongation of dorsal-fin elements (when present) not associated with sexual dimorphism; or dorsal fin, if sexually dimorphic, with first and second dorsal-fin branched rays slightly surpassing dorsal-spine distal tip). The new species is also distinguished from C. longipinnis and C. tukano by the presence of four to six irregular black or brownish blotches on the midline of the flank (vs. midline of the flank with three large black rounded blotches in C. longipinnis; two very large black rounded blotches in C. tukano). Corydoras gryphus is furt

A new long-finned Corydoras Lacépède, 1803 (Siluriformes: Callichthyidae) from the lower rio Paraná basin, Brazil

discussion

Remarks. Fuller & Evers (2011: 64 - 65) mentioned the presence of an undescribed species from the Misiones Province, Argentina (Fig. 5). The presence of irregular and slightly vertically elongated small black blotches along midline of the flank is shared between the new species and Corydoras sp. ‘ Misiones’ (see Figs. 1, 5). On the other hand, Corydoras sp. ‘ Misiones’ present irregular and striated black spots on the snout and dorsal portion of the head, which are absent in C. gryphus. However, Corydoras sp. ‘ Misiones’ present the same unusual sexual dimorphism of C. gryphus, C. longipinnis and C. tukano. Additionally, through the analysis of high-definition photographs, it was possible to observe that Corydoras sp. ‘ Misiones’ also presents a reduced laminar expansion of infraorbital 2 and relatively slender infraorbital 1, similar to C. gryphus condition. Furthermore, the type locality of C. gryphus is relatively near to the territory of Misiones Province. Despite the similarity between the new species and Corydoras sp. ‘ Misiones’, the precise confirmation that they are the same species can only be made through the analysis of preserved specimens of Corydoras sp. ‘ Misiones’.

A new long-finned Corydoras Lacépède, 1803 (Siluriformes: Callichthyidae) from the lower rio Paraná basin, Brazil