Friday, June 1, 2012

[Ichthyology • 2009] Lamontichthys avacanoeiro & L. parakana • Systematics of Lamontichthys Miranda-Ribeiro (Siluriformes: Loricariidae), with the description of two new species


Lamontichthys avacanoeiro
de Carvalho Paixão & Toledo-Piza, 2009

ABSTRACT
The taxonomic revision of the genus Lamontichthys Miranda-Ribeiro, based on the examination of 164 specimens of different river drainages throughout the Amazon basin, revealed the presence of six species of which two are new. Lamontichthys filamentosus occurs in the upper and middle portions of the rio Amazonas basin; L. llanero in the río Orinoco basin; L. maracaibero in the lago Maracaibo basin; and L. stibaros in the upper río Amazonas basin. Lamontichthys avacanoeiro, new species, occurs in the upper rio Tocantins basin; and L. parakana, new species, in the lower rio Tocantins basin. The new species represent a considerable extension in the so far known distribution of the genus. A parsimony analysis, including 87 osteological and external morphological characters from Lamontichthys and related taxa (total of 16), resulted in three most parsimonious trees with 194 steps (CI = 0.73 and RI = 0.78). The hypothesis of monophyly of Lamontichthys is corroborated and supported by six derived characters. Within Lamontichthys two monophyletic assemblages are recognized, one includes L. avacanoeiro and L. stibaros, the other includes L. maracaibero and the clade formed by L. filamentosus and L. llanero. The relationships of Lamontichthys parakana, a species that was not included in the phylogenetic analysis is discussed. The monophyly and relationships of the monotypic genus Pterosturisoma microps are also discussed.
Key words: Loricariinae, Armored catfish, Taxonomy, Neotropical freshwater, Phylogeny.



Lamontichthys avacanoeiro
de Carvalho Paixão & Toledo-Piza, 2009


Lamontichthys parakana 
de Carvalho Paixão & Toledo-Piza, 2009     

Etymology: The species name, parakana, is in reference to the Parakanã, inhabitants of the margins of the lower rio Tocantins, in the State of Pará. Parakanã, an American group that historically inhabited the area of the lower rio Tocantins, drainage from which the examined specimens of the species in this study originated.


Lamontichthys filamentosus (LaMonte, 1935)


Andrea de Carvalho Paixão; Mônica Toledo-Piza. 2009. Systematics of Lamontichthys Miranda-Ribeiro (Siluriformes: Loricariidae), with the description of two new species. Neotropical Ichthyology (Neotrop. Ichthyol.). 7 (4): http://dx.doi.org/10.1590/S1679-62252009000400002

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