Proterocara Argentina, a new fossil cichlid from the Lumbrera Formation, Eocene of Argentina

C, M.; O, Z.; CECILIA EUGENIA DEL PAPA

Journal of Vertebrate Paleontology

Society of Vertebrate Paleontology

Año: 2006 vol. 26 p. 267 - 275

0272-4634

The Lumbrera Formation is the uppermost unit of the Santa Bárbara Subgroup of the Salta Group, exposed in northwestern Argentina. It consists of fine clastic sediments of characteristic brick red color with an intercalation of green mudstone levels, which are called as Faja Verde. The specimens described here were collected from the middle part of the Faja Verde II at the Alemania locality in sediments dated as Eocene. The material comprises a specimen, preserved as mould and conter mould, which is assigned to a new genus and species: Proterocara argentina gen. et sp. nov. The phylogenetic analysis to establish its position within Cichlidae was based on a matrix with 53 taxa and 91 characters. The most parsimonious tree shows P. argentina as sister group of Cichlasomatinae subfamily with basis on only two characters: articulating process of premaxilla moderately distinct and fewer than 15 anal-fin rays. Three autapomorphies are recognized for P. argentina: the ascending arm of premaxilla as long as dentigerous arm, dorsal lateral line on caudal fin between D2 and D3; and more than 3 procurrent caudal-fin rays. Extant members of the family Cichlidae live mostly in lentic freshwater bodies, corroborating the lacustrine paleoenvironment assigned to this formation.