11. Legends
Fig. 1. Haplotype network of COI mitochondrial gene. Areas of the circles are proportional to the number of individuals. Each circle represents a haplotype, dots between haplotypes symbolize mutational steps.
Fig. 2. Phylogenetic trees obtained with Maximum Likelihood and Bayesian Inference approaches. Left, phylogeny constructed with the mitochondrial marker COI. Right, phylogeny constructed with the nuclear marker 18S. Only nodes supported by bootstrap value ≥ 51 and posterior probability ≥ 0,86 are reported. Mirrored pattern of branching clades is observed, dotted lines indicate the only two samples that do not show this congruent pattern. In red group A, in blue group B defined by ABGD species delimitation analysis and the haplotype network of COI.
Fig. 3. Species distribution along the Antarctic Peninsula. Each circle represents a sampling station, in red the proportion ofC. verrucosa sp. A , in blue the proportion of C. verrucosa sp. B , in grey no A/no B (basal branch). Numbers represent sample size.
Fig. 4. Photos. a) specimen with basal disc, b) specimen without basal disc. To the right (c and d) underwater photos taken by Cristian Lagger, in the benthos assemblage of Potter Cove where high diversity of morphological features is observed in C. verrucosa sensu lato.