Latitudinal phenotypic variation in the southernmost trichomycterid, the catfish Hatcheria macraei: an amalgam of population divergence and environmental factors

CHIARELLO-SOSA, JUAN MAURO; BATTINI, MIGUEL; BARRIGA, JUAN PABLO

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2018 vol. 124 p. 718 - 731

0024-4066

Body shape and meristic characters are highlyvariable phenotypic aspects in fish, and in most cases are related to phylogeography,environmental factors and life history patterns. Our main goals were toevaluate morphological and meristic characters in five populations of thecatfish Hatcheria macraei living at different latitudes across Patagonia, and to assess the importance ofenvironmental and phylogenetic variables in determining body shape. Thepresent study reveals great morphological variation among populations distributed along thelatitudinal gradient. We found that the highest levels of variation in external morphologicalfeatures were in peduncle height, dorsal fin length and anus position. This variationin body shape, quantified by geometric morphometrics, was mostly explained by thephylogenetic relationship between populations, stream gradient and spawningtemperature. In contrast, the meristic characters, such as vertebral and finray numbers, except for dorsal fin ray number, were negatively related tolatitude and positively to spawning temperature.