Fig. 1
From: Adaptation and convergence in circadian‐related genes in Iberian freshwater fish
a Spatial distribution of the four Western Iberian Squalius species in Portugal, sampling sites and representation of environmental differences. b Cladogram illustrating the phylogeny of the four Western Iberian Squalius species, according to Sousa-Santos et al. (Ref. 28). Sampling sites are marked with red triangles: Mondego basin (1, Sótão river); Tagus basin (2, Ocreza river); Almargem basin (3, Almargem stream); Mira basin (4, Torgal stream); Arade basin (5, Odelouca stream). Axes on map represent latitude and longitude, respectively. The map was created with QGIS software (https://qgis.org) and edited with Inkscape (https://inkscape.org)