Pimelodella taenioptera Miranda Ribeiro, 1914

Díaz, Federico Ruíz, Soneira, Paula, Almirón, Adriana, Casciotta, Jorge, Gonzalez, Alfredo, Pimelodella, Sebastián Sánchez Abstract & The, Paraguay., 2008, First record of Pimelodella taenioptera Miranda Ribeiro, 1914 (Siluriformes, Heptapteridae) from the río Paraná above río Paraguay confluence, Argentina., Ichthyological Contributions of PecesCriollos 10, pp. 1-4 : 1-3

Pimelodella taenioptera Miranda Ribeiro, 1914

Material examined

Pimelodella taenioptera : AI 243 1 ex., 130.0 mm SL, Argentina, Corrientes province, río Paraná at Yahapé 27°22’12.1''S - 57°39’14.6''W. coll: A. Gonzalez et al., November, 2006. AI 244 1 ex., 152.8 mm SL, Argentina, Corrientes province, río Paraná at Itá-Ibaté (27°25’49.7''S - 57°21’59.9''W). coll: A. Gonzalez et al., November, 2007. AI 245 1 ex., 177.5 mm SL, Argentina, Corrientes province, río Paraná at Itá-Ibaté (27°25’49.7''S - 57°21’59.9''W). coll: A. Gonzalez et al., February, 2007 .

Description

This species can reach 180 mm. Morphometry of Pimelodella taenioptera are provided in table 2 . Body elongate and slender (five or six times in SL). Head short and large eyes. Maxillary barbels surpassing the anal fin origin, mental ones reaching the pectoral fin and the post mental ones reaching the dorsal fin origin. Dorsal fin origin nearer snout tip than caudal fin base. Adipose fin long, 2.0-2.3 times in standard length. Pectoral spine shorter than head length, serrated on anterior and posterior border. Caudal fin deeply forked, upper lobe much longer than lower one.

Colour in life

Ground colour silvery grey ( Fig. 1 ). Head and flanks and caudal fin with a dark stripe. Middorsal body with a black stripe from the rear part of head to the end of adipose fin. Dorsal and pectoral fin smoky.

Habitat

The specimens of Pimelodella taenioptera were collected in February and November of 2006 and 2007 in coastal areas of a narrowed reach of the Río Paraná main channel, downstream a prominent sandstone outcrop ( Fig. 2 ). The main environmental variables of the habitat are presented in table 1 . Depth varied between 1.5-2.5 m and the bottom was composed mostly by large boulders of sandstone with patches of sand and pebbles.

The species was found in well oxygenated waters having moderate to high current speed.

Distribution:

Pimelodella taenioptera was captured in the río Paraná close to Yahapé (27°22’12.1''S - 57°39’14.6''W) and Itá-Ibaté (27°25’49.7''S - 57°21’59.9''W) towns ( Fig. 3 ).

Figures

Fig.1. Lateral view of Pimelodella taenioptera upon capture.

Fig. 2. Río Paraná at Yahapé, where Pimelodella taenioptera was collected.

Fig. 3. Map showing the collecting sites of Pimelodella taenioptera in the río Paraná: 1. Yahapé. 2. Itá-Ibaté