Table 1.
Genetic diversity values, mismatch distribution parameters, neutrality, and demographic expansion test for the Megabalanus azoricus populations sampled and haplogroups detected.
Fig 1.
Sampling locations and haplogroup frequencies.
Image (NASA) of the north-eastern Atlantic area indicating the sampling locations for each of the Macaronesian archipelagos. Arrows indicate the main surface currents and their directions. Haplogroup (α, β, and γ) frequencies estimated for each sampling site are presented in pie charts.
Fig 2.
Exterior (A) and interior (B) views of scuta and exterior (D) and interior (C) view of terga from a Megabalanus azoricus individual sampled in the Azorean archipelago (Terceira Island).
Fig 3.
Phylogenetic tree within the Megabalanus genus.
Phylogenetic tree based on the Bayesian criterion and elaborated with MrBayes from 16SrRNA sequences with distance calculated by the GTR model. Megabalanus sequences available from Genbank were included in the analysis, which incorporated 16S rRNA sequences obtained from M. tulipiformis and M. azoricus specimens (in blue color). Branch support is indicated by the numbers on branches, reflecting the Bayesian analysis posteriori probabilities in percentages. The Elminius modestus sequence was used as an outgroup.
Fig 4.
Regression plot of the haplotype diversity and nucleotide diversity.
Regression analysis of haplotype diversity (h) (blue line) and nucleotide diversity (π) (green line) from mitochondrial control region sequences of the Azorean barnacle (Megabalanus azoricus), with respect to sampling site latitudes (Azorean, Madeira, Canary, and Cabo Verde archipelagos).
Fig 5.
Haplotype network for Megabalanus azoricus.
A. Haplotype network using a median joining algorithm from the Megabalanus azoricus mitochondrial control region DNA sequence alignment. Each code-colored circle represents a single haplotype, whose area is proportional to the haplotype frequency. The length of the connecting lines is proportional to the number of mutational steps. B. Neighbor-joining optimal mid-point rooted tree with the distance measured by the selected Tamura-Nei model, including a rate variation among sites with shape α = 0.21 for the gamma distribution. Branch support was estimated by bootstrapping (2,000 replicates).
Table 2.
FST estimations from pairwise comparisons among the populations of Macaronesian Megabalanus azoricus sampled using the mitochondrial control region data.
Table 3.
Analysis of molecular variance (AMOVA) based on the mitochondrial control region sequences of the Azorean barnacle, Megabalanus azoricus.
Fig 6.
Mismatch distributions for Megabalanus azoricus.
Mismatch distributions estimated for (A) each of the sample sites in the four Macaronesian archipelagos (Azores, Madeira, Canary, and Cabo Verde Islands) and (B) for the three identified haplogroups distributed along the Macaronesian sampling sites.
Fig 7.
Bayesian skyline plot for Megabalanus azoricus haplogroups.
Bayesian skyline plot based on mitochondrial control region coalescent analysis for the Megabalanus azoricus haplogroups.