Astyanax puka

Astyanax puka Mirande, Aguilera & Azpelicueta 2007

A. puka Mirande, Aguilera & Azpelicueta, 2007 NEW New species> details

List of Freshwater Fishes from Argentina - Update 9.

description

Description: Morphometrics of the holotype, and 19 paratypes are presented in Table 1. Body rather slen- der (33.5 – 39.8 % SL), with maximum depth at dorsal-fin origin. Dorsal profile slightly convex over snout and straight from interorbital area to tip of supraoccipital process; slightly convex to dorsal-fin origin; straight from this point to caudal peduncle; gently concave along caudal peduncle to base of caudal-fin rays. Ventral profile of body convex from lower-jaw tip to anal-fin origin; straight to anal-fin origin; slanted dorsally to end of anal fin, and almost straight under caudal peduncle. Ventral portion of body between bases of pectoral and pelvic fins transversally rounded; ventral portion of body between origins of pelvic and anal fins more compressed laterally. Dorsal-fin origin equidistant from snout tip and caudal-fin origin. Pelvic-fin origin located slightly anterior to vertical through dorsal-fin origin. Anal-fin origin located just behind vertical line through base of posteriormost dorsal-fin rays. Tip of pectoral fin reaching pelvic-fin origin, and tip of pelvic fin reaching anal-fin origin in males and some females. Mouth terminal, placed at level of inferi

A new species of Astyanax (Characiformes: Characidae) from the endorheic R o Sal basin, Tucumán, northwestern Argentina

diagnosis

Diagnosis: Astyanax puka is distinguished from the remaining species of the genus by the following combination of characters: shallow body (33.5 – 39.8 % SL), 36 – 38 perforated scales in lateral line, 6 / 5 transverse scales, 9 – 10 gradually decreasing dentary teeth, distally expanded premaxillary teeth, one distally expanded maxillary tooth with 7 – 9 cusps, short upper-jaw length (34.5 – 37.8 % HL), short maxilla (20.7 – 23.3 % HL) expanded abruptly under maxillary tooth position, short postorbital distance (36.6 – 46.9 % HL), short pelvic to anal-fin origin distance (17.1 – 20.6 % SL), 22 – 27 branched anal-fin rays, long caudal peduncle (13.3 – 16.5 % SL), bony hooks restricted to pelvic-fin rays 2 to 6 and anterior 6 – 13 branched anal-fin rays on mature males, and the presence of broad denticles on anterior, lateral, and posterior edges of first ceratobranchial gill rakers. A detailed comparison of Astyanax puka with the other species of Astyanax appears in the “ Discussion ” section below in this paper.

A new species of Astyanax (Characiformes: Characidae) from the endorheic R o Sal basin, Tucumán, northwestern Argentina

distribution

Distribution: Astyanax puka is known only from the Mandolo and Salί rivers, Rίo Salί endorheic basin, Tucumán, northwestern Argentina (Fig. 4). Habitat notes: The type locality is approximately one-meter deep and has a gravel bottom, with slow current.

A new species of Astyanax (Characiformes: Characidae) from the endorheic R o Sal basin, Tucumán, northwestern Argentina