Taxonomic revision and phylogeny of Loricariichthys Bleeker, 1862 (Ostariophysi: Siluriformes: Loricariidae)

Author(s)

Andrea de Carvalho Paixão

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB)
• Defense date: 2012-12-11

Examining board members

Mônica de Toledo Piza Ragazzo; Heraldo Antonio Britski; Marcelo Rodrigues de Carvalho; Roberto Esser dos Reis; Mónica Sonia Rodriguez

• Advisor: Mônica de Toledo Piza Ragazzo

Abstract

This main goals of this study were to taxonomically review the species of the genus Loricariichthys Bleeker, 1862 (Siluriformes, Loricariidae); to update the information on the geographical distribution of all species of the genus; to propose a hypothesis of phylogenetic relationships among these species and to test the hypotheses of the monophyly of Loricariichthys and its relationships with other Loricariinae. Seventeen species are recognized, of which three are new: Loricariichthys sp. n. 1 occurs in the rio Orinoco basin; Loricariichthys sp. n. 2 in the basin of the rio Tocantins-Araguaia, and Loricariichthys sp. n. 3 in the rio Madeira basin. The nominal species L. chanjoo (Fowler, 1940) and L. ucayalensis Regan, 1913 are considered junior synonyms of L. stuebelii (Steindachner, 1882), both described from the rio Ucayali basin, in Peru. From the same basin, L. cashibo (Eigenmann & Allen, 1942) is tentatively considered a junior synonym of L. hauxwelli Fowler, 1915. Loricariichthys brunneus (Hancock, 1828) described from the Orinoco River basin, is considered \"species inquirenda.\" A phylogenetic analysis based on 84 morphological characters and 54 taxa resulted in 36 most parsimonious cladograms (IC = 43, IR = 87), that were summarized in a strict consensus cladogram. Loricariichthys was corroborated as monophyletic based on five exclusive synapomorphies, and the genus is hypothesized as the sister group of Hemiodontichthys. Eight monophyletic taxa at different levels of universality were proposed within the genus. Phylogenetic relationships among members of the Loricariinae are also discussed (AU)