Tatia neivai (Ihering, 1930)

(figs. 5-7)

Material examined

All from Argentina: MISIONES Province: río Paraná basin. MLP 10605, 1 ex., 64.8 mm SL, arroyo Piray Guazú (26°26'34.1" S, 54°08'29.4" W), coll: Almirón, Casciotta, Říčan & Piálek, February, 2012. MLP 10606, 1 ex., 81.4 mm SL, arroyo Tabay (26º59’56.3”S - 55º10’44.9”W), coll: Almirón, Casciotta, Říčan & Piálek, October, 2009 . MLP 10607, 1 ex., 53.4 mm SL, arroyo Garupá (27º29’10.2”S - 55º44’23.1”W), coll: Almirón, Casciotta, Říčan & Piálek, October, 2009 . CI-FML 5900, 2 ex., 27.5-80.0 mm SL., camping Tropical en arroyo Garuhapé (26°48'20,24'' S - 54°56'11,82'' W), coll: Aichino & Benitez, May, 2011 . Laboratorio de Genética Evolutiva de la UNAM-Peces (LGE-P) 13; 1 ex., 29.3 mm, camping Tropical en arroyo Garuhapé (26°48'20,24'' S- 54°56'11,82'' W), coll: Aichino & Benitez, May, 2011 . CI-FML 5901, 1 ex., 35.8 mm SL., río Paraná at Puerto Nemesio Parma (27°21'14,36''S- 56°00'15,18'' W), coll: Aichino, November, 2011 . LGE-P 14; 1 ex., 37.2-40.9 mm, río Paraná at Puerto Nemesio Parma (27°21'14,36''S - 56°00'15,18'' W), coll: Aichino, November, 2011 . CORRIENTES Province: CI-FML 5902, 1 ex, 35.0 mm SL, río Paraná at Ituzaingó (27°29'26,55''S - 56°40'51,63''W), coll: Aichino & Benitez, March, 2012

Description

Tatia neivai is distinguished from the other species of the genus by its colour pattern with dark flanks bearing small white horizontally elongated dots, different in small specimens (fig. 5). The species is also distinguished by the presence of a broad third nuchal plate, with a short lateral projection and the cranial fontanel bound by mesethmoid and frontal. Morphometric data are presented in table 1.

Habitat

Most of the environments where T. neivai was found had sandy and rocky bottom with fast flowing water, excluding Nemesio Parma and Ituzaingó in which the water is quiet with submerged allochthonous vegetation and sandy and muddy bottom.

Distribution

Tatia neivai is known from the upper Paraguay and Paraná river, and upper Paraíba do Sul in Brazil (Sarmento-Soares & Martins-Pinheiro, 2008). The specimens collected herein come from several streams and the main channel of the middle río Paraná (fig. 7).