Redescription of Astyanax multidensEigenmann, 1908 (Characiformes: Characidae), a small characid of the Brazilian Amazon

Manoela M F Marinho,José L O Birindelli

doi:10.1590/s1679-62252013000100005

Manoela M F Marinho, José L O Birindelli

Open Access

https://doi.org/10.1590/s1679-62252013000100005

Copy DOI

Abstract

Astyanax multidensis redescribed based on syntypes and additional specimens from the rio Amazonas at Silves, Amazonas State and Óbidos, Pará State, and the rios Trombetas, Tapajós, Xingú, and Araguaia.Astyanax multidensis distinguished from congeners by the unique combination of five to seven maxillary teeth, 31 to 34 pored lateral-line scales, 20 to 23 branched anal-fin rays, and a dark triangular blotch restricted to the middle caudal-fin rays. Astyanax multidens was collected syntopically with Jupiaba paranatinga in the rio Tapajós basin and with Jupiabacf. essequibensis in the rio Xingu basin, which have paired anteriorly oriented pelvic-fin spines, a antipredatory mechanism. Based on the external morphological similarity betweenAstyanax multidens and the two species ofJupiaba, their sympatric occurrence, and their distinct phylogenetic position, we interpret this a case of Batesian mimicry.

Highlights

The family Characidae is the fourth largest family of fishes in the World, with over 1.100 valid species, being smaller only than the freshwater families Cyprinidae, Cichlidae, and the mainly marine Gobiidae (Nelson, 2006; Eschmeyer & Fricke, 2012)
Astyanax multidens is distinguished from all congeners except A. angustifrons (Regan), A. aurocaudatus Eigenmann, A. gisleni Dahl, A. goyanensis (Miranda Ribeiro), A. guaporensis Eigenmann, A. guianensis Eigenmann, A. henseli Melo & Buckup, A. leopoldi Géry, Planquette & Le Bail, A. nasutus Meek, A. nicaraguensis Eigenmann, A. superbus Myers, and A. totae Haluch & Abilhoa by having five to seven maxillary teeth
Astyanax multidens is distinguished from the aforementioned species, except A. angustifrons, A. guaporensis, A. guianensis, A. leopoldi, A. nicaraguensis, and A. totae by having 31 to 34 pored lateral-line scales

Summary

Introduction

The family Characidae is the fourth largest family of fishes in the World, with over 1.100 valid species, being smaller only than the freshwater families Cyprinidae, Cichlidae, and the mainly marine Gobiidae (Nelson, 2006; Eschmeyer & Fricke, 2012). Contrary to these three families, the Characidae is much more geographically limited, being restricted to South America, from Texas (U.S.A.) to Argentina. Increasing are the contributions through redescriptions of poorly known species (e.g., Garutti, 2003; Mirande et al, 2006; Garutti & Langeani, 2009; Pavanelli & Oliveira, 2009; Azpelicueta & Loureiro, 2009; Almirón et al, 2010; Bertaco et al, 2010; Bertaco & Lucena, 2010; Soneira et al, 2010)

Methods

Results

Conclusion