Genetic divergence and isolation by distance in the West Atlantic sea anemone Actinia bermudensis (McMurrich, 1889)

Molecular and morphological evidence thatPhymactis papillosafrom Argentina is, in fact, a new species of the genusBunodosoma(Cnidaria: Actiniidae)

“…papillosa from Argentina (Figure 3). However, the genetic distance values between those two species (D ranging from 0.345 to 0.399) were within the range usually found between different species of the same genus (Thorpe & Solé-Cava, 1994; Vianna et al , 2003). Furthermore, those two species showed a high degree of gene frequency differentiation across loci (Fisher's exact test; P < 0.0001), confirming their genetic distinctiveness.…”

“…Genetic distance found between Phymactis papillosa from Chile and the putative P. papillosa from Argentina was very large, at a level typically found between different genera (Thorpe & Solé-Cava, 1994; Vianna et al , 2003). The smallest gene divergence was found between the two Bunodosoma cangicum populations (D = 0.009; Table 2).…”

“…Heterozygosity levels (H) were high in most populations (Table 1) but were well within the range of Thorpe, 1989;Russo et al, 1994). Genetic distance found between Phymactis papillosa from Chile and the putative P. papillosa from Argentina was very large, at a level typically found between different genera Vianna et al, 2003). The smallest gene divergence was found between the two Bunodosoma cangicum populations (D ¼ 0.009; Table 2).…”

“…In fact, large estuaries such as the Amazon River delta are an important source of phylogeographical breaks for costal marine species (Rocha et al , 2002; Lima et al , 2005; Currie & Small, 2006). Although the Amazon River estuary did not seem to be an important barrier to gene flow (Vianna et al , 2003) for the sea anemone species Actinia bermudensis , that species is known to withstand large salinity variations, inhabiting estuaries (Stephenson, 1935; Corrêa, 1964; Douek et al , 2002) where Bunodosoma species are never found (Gomes, 2002). So far few papers have analysed the role of the La Plata River as a gene flow barrier for marine animals but Zamponi et al (1998a) have already called attention to this estuary as a potential barrier to cnidarian dispersal, since the Brazilian and Argentinean coasts only share three species of sea anemones out of more than 50 presently recognized species in the two areas.…”

Genetic structuring and species boundaries in the Atlantic stony coral Favia (Scleractinia, Faviidae)

“…Strong genetic differentiation between species that span the Brazilian and Caribbean biogeographic provinces has been widely recorded for marine organisms based on different genetic markers, for instance, allozymes in sea anemones (Vianna et al., 2003), mtDNA of the intertidal fiddler crab Uca rapax (Laurenzano et al., 2013), wrasses (Rocha et al., 2005) and bridled gobies (Volk et al., 2021, which also analysed SNPs), and microsatellites of reef sharks (Bernard et al., 2017). The same pattern was also recovered in reef‐building corals (Nunes et al., 2009), including Favia spp.…”