Deconstructing an assemblage of "turtle" barnacles: species assignments and fickle fidelity in Chelonibia

摘要: Barnacles in the genus Chelonibia are commensal with a variety of motile marine animals including sea turtles, crustaceans, and sirenians. We conducted worldwide molecular phylogenetic survey collected from nearly all known hosts to assess species relationships, host-fidelity, phylogeographic structure. Using DNA sequences protein-coding mitochondrial gene (COI), rRNA (12S), one nuclear (28S), we found that four species, three (C. testudinaria, C. patula, manati) genetically indistinguishable. In addition, show each utilizes rare androdioecious mode reproduction involving complemental males. contrast, fourth caretta), which is hermaphroditic specializes on distinct—leading conclusion former taxa morphotypes same should be synonymized under testudinaria. Phylogenetic analysis resulted geographic clades (Atlantic, Indian Ocean/western Pacific, eastern Pacific) haplotype parsimony networks revealing no shared haplotypes among regions. Analysis variance detected significant differences by region (p < 0.005); conversely, there were when grouped host or taxonomic designation. Average pairwise genetic distances lower between Pacific Atlantic (0.053 ± 0.006) than (0.073 ± 0.008), suggesting populations connected more recently, perhaps until rise Isthmus Panama. Host use discussed along speculation possible ancestral support for “turtle-first” hypothesis.