2026/01/01 by Thiago Silva Loboda · 1 voice
Environmental Science · Agricultural and Biological Sciences · #Fish biology, ecology, and behavior #Ichthyology and Marine Biology #Fish Biology and Ecology Studies
paper · doi:10.1590/1982-0224-2025-0087
openalex publication_date 2026/01/01 · openalex created_date 2026/04/21 · openalex updated_date 2026/05/21
Abstract The second most diverse genus of the Potamotrygonidae, Paratrygon, with three previously recognized species, P. aiereba, P. orinocensis and P. parvaspina, is here expanded, with the description of four new species, each endemic to one of the four largest clear water rivers in the Amazon basin: Tapajós, Xingu, Araguaia and Tocantins. The new taxa occur in the middle and upper portions of their respective rivers, which originate and flow from the Brazilian Crystalline Shield. They are recognized by morphological characters such as coloration, dentition, morphometrics, morphology and distribution of dermal denticles and caudal spines, distribution of ventral canals of the lateral line system, and morphology and structure of major skeletal elements. Previously published molecular studies also confirm the validity of these species, and their data have been considered in the discussion. The description of these four new species and the reconfiguration of the distribution of P. aiereba in the Amazon basin led to a discussion of the possible influence of the water types of the Amazonian rivers on the diversity found in the genus. The hypothesis regarding this type of influence in potamotryginins was recently proposed by other authors. A key to identification of the species of Paratrygon is provided.