Austrolebias paucisquama (Cyprinodontiformes: Rivulidae), a new species of annual killifish from southern Brazil

Juliano Ferrer,Luiz R Malabarba,Wilson J E M Costa

doi:10.1590/s1679-62252008000200004

Abstract

Austrolebias paucisquama is described from the rio Vacacaí drainage, a tributary to the rio Jacuí, Rio Grande do Sul, Brazil. The new species belongs to the Austrolebias alexandri species-group, by sharing the apomorphic bright blue iridescence and dark gray pectoral fins in males. It is distinguished from other species of this group by having fewer scales around caudal peduncle (12) and fewer dorsal-fin rays in males (17-21). The lack of contact organs on the inner surface of the pectoral fin in males and the color pattern of females - ground color light brownish, sides of body with a variable number of relatively large dark black spots distributed mostly on posterior portion of body - distinguish A. paucisquama from all other species of the genus.

Highlights

Austrolebias Costa is a genus of annual killifishes whose species inhabit seasonal and temporary pools and swamps formed during the rainy season in southern Brazil, Paraguay, Uruguay, and north and northeast Argentina (Costa, 2006)
In a more recent review, Costa (2006) redefined the group based on the apomorphic dark gray pigmentation of the pectoral fins and the bright blue iridescence in males, and has expanded the group including A. duraznensis (García, Scvortzoff & Hernandéz), A. juanlangi Costa, Cheffe, Salvia & Litz, A. litzi Costa, A. nigripinnis (Regan) and A. paranaensis Costa
The species A. luzardoi described by Perujo et al (2005) belongs to this group.We describe a new species of Austrolebias from the rio Vacacaí drainage, a tributary of the rio Jacuí, Rio Grande do Sul, Brazil

Summary

Introduction

Austrolebias Costa is a genus of annual killifishes whose species inhabit seasonal and temporary pools and swamps formed during the rainy season in southern Brazil, Paraguay, Uruguay, and north and northeast Argentina (Costa, 2006). The genus has been recently phylogenetically redefined by Costa (2006), including the species previously referred to Megalebias Costa. In a more recent review, Costa (2006) redefined the group based on the apomorphic dark gray pigmentation of the pectoral fins and the bright blue iridescence in males, and has expanded the group including A. duraznensis (García, Scvortzoff & Hernandéz), A. juanlangi Costa, Cheffe, Salvia & Litz, A. litzi Costa, A. nigripinnis (Regan) and A. paranaensis Costa. The species A. luzardoi described by Perujo et al (2005) belongs to this group.We describe a new species of Austrolebias from the rio Vacacaí drainage, a tributary of the rio Jacuí, Rio Grande do Sul, Brazil. The new species belongs to the Austrolebias alexandri species-group

Material and Methods

Results

Discussion

Literature Cited