Morphologic and genetic variation within a relict Andean catfish, Hatcheria macraei, and its relationship with Trichomycterus areolatus and Bullockia maldonadoi (Siluriformes: Trichomycteridae)

BECKER, LEANDRO; BATTINI, MIGUEL; BARRIGA, JUAN; AZPELICUETA, MERCEDES; JOHNSON, JERALD; CUSSAC, VÍCTOR

ANAIS DA ACADEMIA BRASILEIRA DE CIENCIAS.

ACAD BRASILEIRA DE CIENCIAS

Lugar: Rio de Janeiro; Año: 2023

0001-3765

The South American siluriform fishes are found primarily inthe Neotropical region, north and east of the Colorado River of Argentina, witha few relict species distributed southward and westward on both sides of theAndes Mountains. Three of these, the closely related trichomycterids Hatcheriamacraei, Trichomycterus areolatus and Bullockia maldonadoi, have been subjectto historical taxonomic and nomenclatural arrangements. Here, we amplify a652-bp fragment of COI mtDNA from 55 H. macraei individuals and use publiclyavailable Cytb mtDNA sequences of the three taxa to assess their relationship,genetic variation and haplotype distribution in relation to hydrographicbasins. In addition, we extend a recent morphometric study on H. macraei byanalyzing body shape in 447 individuals collected from 24 populations acrosstheir entire cis-Andean distribution. We identified some lineages previouslyassigned to T. areolatus that show a closer relationship to either B.maldonadoi or H. macraei, revealing new boundaries to their currently knowntrans-Andean distribution. We found a great morphologic variation among H.macraei populations and a high genetic variation in H. macraei, T. areolatusand B. maldonadoi associated with river basins. We highlight further integrativestudies are needed to enhance our knowledge of the southern Andeantrichomycterid diversity.