Thorichthys Meek 1904

Phylogenetics of Thorichthys and T. panchovillai Sequence length in our final alignment (n = 55) ranged from 784 to 1065 base pairs (bp), and only two sequences were shorter than 1000 base pairs, T. panchovillai FMNH 152716.2 (784 bp) and T. panchovillai FMNH 151316.2 (833 bp). Both Bayesian and maximum likelihood phylogenetic analyses recovered two major clades within the genus Thorichthys (Fig. 2), supported by Bayesian posterior probabilities (BPP = 1) and bootstrap support values (BS =100). One clade was composed of three species (T. affinis, T. meeki, and T. pasionis; Fig. 2) and a deeply divergent sister lineage of samples identified as T. helleri from the Grijalva-Usumacinta Area of Endemism (AoE sensu Elías et al. 2020), hereafter referred to as T. cf. helleri (Fig. 2). It is worth noting that samples of T. affinis and T. meeki were not recovered as reciprocally monophyletic (Fig. 2). The second major clade was composed of six species (viz. T. aureus, T. callolepis, T. helleri, T. maculipinnis, T. panchovillai, and T. socolofi; Fig. 2). Within this clade we inferred two strongly supported sub-clades (BPP = 1, BS = 84; Fig. 2), one which includes two species, T. callolepis and T. maculipinnis (BPP = 1, BS = 100), and the other clade comprised of T. aureus, T. helleri, T. panchovillai, and T. socolofi. Phylogenetic relationships of this clade recovered T. aureus as the sister of a clade comprised of T. helleri, T. panchovillai, and T. socolofi with strong support (BPP = 1, BS = 84), in which T. helleri was recovered as the sister of T. panchovillai + T. socolofi with strong support (BPP = 1, BS = 92; Fig. 1); (T. aureus, (T. helleri, (T. panchovillai, T. socolofi ))) (Figs. 2 and 3).