Tylos Audouin, 1826

López-Orozco, Carlos Mario, Carpio-Díaz, Yesenia M., Borja-Arrieta, Ricardo, Navas-S, Gabriel R., Campos-Filho, Ivanklin Soares, Taiti, Stefano, Mateos, Mariana, Olazaran, Alexandra, Caballero, Isabel C., Jotty, Karick, Gómez-Estrada, Harold & Hurtado, Luis A., 2022, A glimpse into a remarkable unknown diversity of oniscideans along the Caribbean coasts revealed on a tiny island, European Journal of Taxonomy 793, pp. 1-50 : 38

Molecular phylogenetic analyses of Tylos Audouin, 1826

Sequences obtained for the three species of Tylos from Isla Grande and the specimen from Florida have been deposited under GenBank Accession Numbers MW532964 – MW532970 and MW533069 – MW533075 . Only the 12S rDNA sequence was obtained for the specimen from Isla Grande assigned to T. marcuzzii . Phylogenetic analyses using only 12S rDNA group this sequence with the two specimens of T. marcuzzii from Cuba reported in Hurtado et al. (2014); see Fig. 18 . The 12S rDNA p-distance between T. marcuzzii from Isla Grande and T. marcuzzii from Cuba is 2.0–2.7%, whereas the distance between the specimens from the two Cuban localities is 2.0% ( Table 2 ). Only the 16S rDNA sequence was obtained for the specimen of T. niveus from the Florida Keys, the type locality of this species. Phylogenetic analyses of 16S rDNA show that specimens identified as T. niveus from Isla Grande are most closely related to the T. niveus specimen from the Florida Keys. The 16S rDNA p-distance between T. niveus from Isla Grande and the Florida Keys is 2.7% ( Table 2 ).

The concatenated (12S rDNA and 16S rDNA) dataset was comprised of 43 taxa and 740 characters (excluding characters with ambiguous homology), 236 of which were parsimony-informative. The specimens assigned to T. marcuzzii were used as outgroup. Five main lineages were identified for the ingroup taxa in the concatenated phylogenetic analyses, which formed a basal polytomy ( Fig. 18 ): (1) T. niveus from Puerto Rico; (2) Tylos sp. from Yaguanabo, Cuba; (3) T. niveus from Florida and Isla Grande; (4) T. negroi sp. nov.; and (5) Tylos punctatus sensu lato from the Northeastern Pacific. The range of 16S rDNA and 12S rDNA p-distances between the four basal lineages excluding T. punctatus is 11.1–13.6% and 9.7–15.5%, respectively. The range of 16S rDNA and 12S rDNA p-distances between these ingroup lineages and T. marcuzzii is 19.4–22.2% and 19.5–23.8%, respectively.

Figures

Fig. 18. Phylogenetic relationships among lineages of Tylos Audouin, 1826 from Isla Grande and their closest relatives. Majority rule consensus tree of the Bayesian posterior distribution (GTR+G+I model; 2 runs; 4 million generations; sampled every 1000; 10% burn-in), based on the dataset combining the 12S rDNA and 16S rDNA genes (Supplementary file 3). Nodes with less than 70% support (posterior probability, bootstrap, and SH-aLRT) for any dataset have been collapsed. Dashed lines represent relationships redrawn based on single gene analyses (Supplementary file 1 and Supplementary file 2). The split between the outgroup (T. marcuzzii) and the ingroup received 100% support in all analyses. Specimens from Isla Grande, Colombia are marked with a star. GenBank accession numbers for newly generated sequences are provided in parentheses.