Tuesday, May 15, 2012

[Ichthyology • 2006] Australoheros facetus • Character- and tree-based delimitation of species in the ‘Cichlasomafacetum group (Teleostei, Cichlidae) with the description of a new genus

Fig. 2. Australoheros facetus (Jenyns, 1842) pair in breeding coloration showing the genus specific apomorphy of interruption of the dorsal portion of the abdominal bars.

The  ‘Cichlasoma’ facetum group is part of the taxonomically complex group of Neotropical cichlid fishes of the tribe Heroini. Many species groups and unplaced species of heroines are still left without a generic name following the revision of the genus Cichlasoma. We describe here the ‘Cichlasoma’ facetum group as a new genus, Australoheros, and provide evidence for its monophyly based on phylogenetic analyses of morphological and mtDNA characters. Australoheros is morphologically characterized by the lowest values in meristic characters among heroines and by three apomorphic characters in coloration pattern. In addition to the three described species of Australoheros, our results of species delimitation based on a combination of tree- and character-based approaches identify seven putatively new species of Australoheros. Several coding schemes of morphological characters are used to recover the intrageneric relationships within the genus, resulting in very similar topologies. Discovery of additional species within the genus is expected once material from the whole distribution area is studied.

Key words:Cichlasomafacetum group – Australoheros new genus – species delimitation – phylogeny – Cichlidae – South America

Rícan, O. & S. O. Kullander. 2006. Character- and tree-based delimitation of species in the ‘Cichlasoma’ facetum group (Teleostei, Cichlidae) with the description of a new genus