A New Diminutive Species of Loricaria (Siluriformes: Loricariidae) from the Rio Paraguay System, Mato Grosso do Sul, Brazil

Author(s)

Rodriguez, Monica S. ; Cavallaro, Marcel R. ; Thomas, Matthew R.

• Document type: Journal article
• Source: Copeia; v. N/A, n. 1, p. 8-pg., 2012-03-30.

Abstract

Loricaria coximensis. new species, is described from the Rio Paraguay basin, in Mato Grosso do Sul State, Brazil. It is distinguished from all other species of Loricaria, except L. holmbergi, L. lundbergi, L. parnahybae, and L. pumila by having abdominal plates confined to the pre-anal shield and posterior median abdominal area, usually loosely joined or separated by naked areas, pectoral girdle mostly naked, with isolated plates near base of pectoral fins and posterior to gill opening vs. abdominal plates well developed and tightly arranged across the entire median abdominal area, including the pectoral girdle. It is distinguished from these other four species by meristic counts and several morphometric proportions, particularly a broader head (19.4-21.3% SL vs. 14.1-19.1% SL). Loricaria coximensis becomes the third described paedomorphic species of Loricaria, along with L. nickeriensis and L. pumila, based on its small adult size (<100 mm SL), reduced number of lateral dermal plates, and incomplete abdominal plate development. The new species is presently known only from a limited section of the Rio Coxim, which has been severely impacted by a hydroelectric dam and widespread conversion of land for agriculture. (AU)

• FAPESP's process: 09/54931-0 - Improvement and management of biological specimen collections at the Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo
• Grantee: Carlos Alberto Garofalo
• Support Opportunities: Research Infrastructure Program - Biological specimen collections
• FAPESP's process: 07/04701-2 - Phylogenetic relationships and biogeography of fishes of the subfamily Loricariinae based on morphological data (Siluriformes: Loricariidae)
• Grantee: Mónica Sonia Rodriguez
• Support Opportunities: Scholarships in Brazil - Post-Doctoral