Fig 1.
Sampling locations of the forkbeard in the Northeast Atlantic Ocean and the Mediterranean Sea.
A—Azores archipelago; M—Madeira archipelago; P—mainland Portugal; S—Spain; I—Italy; C—Croatia. Black dots—samples collected for both geometric morphometric and genetic analyses. Black triangles—samples collected for genetic analysis (adapted from Wikimedia Commons, https://commons.wikimedia.org).
Fig 2.
Anatomic landmarks used on forkbeard geometric morphometric analysis.
1 –snout tip; 2 –base of the first dorsal fin; 3 –between first and second dorsal fins; 4 –posterior end of the second dorsal fin; 5 –end of lateral line; 6 –posterior end on anal fin; 7 –anterior insertion of the anal fin; 8 –superior insertion of the pectoral fin; 9 –insertion on the pelvic fin; 10 –posterior limit of the operculum; 11 –mid-point of the posterior extremity of upper-jaw; 12 –insertion of the barbell; 13 –top of the head.
Table 1.
Procrustes distances between mean body shapes of the forkbeard from the three study areas from the Northeast Atlantic.
Fig 3.
Mean body shapes of the forkbeard from the three study areas from the Northeast Atlantic.
Each image represents the transformation from the overall mean shape (grey line) to the mean shape for each location (black line). Numbers represent anatomic landmarks identified in Fig 2.
Fig 4.
Two-dimensional ordination of forkbeard specimens from the three study areas from the Northeast Atlantic based on canonical variate analysis (CVA).
Azores—black squares; Madeira—open triangles; mainland Portugal—grey circles. Plus signs indicate the class centroids.
Table 2.
Jackknife classification matrix of the discriminant canonical analysis applied to the forkbeard from Northeast Atlantic Ocean.
Table 3.
Summary of haplotypes distribution, and haplotype and nucleotide diversities for forkbeard populations.
Fig 5.
Median-joining haplotype network of the forkbeard from the Northeast Atlantic Ocean and the Mediterranean Sea for cytochrome b (846 bp).
The size of each circle is proportional to the number of specimens carrying each haplotype, in which the smallest circles correspond to one individual, and the length of each line is proportional to the number of mutations.
Table 4.
Analysis of molecular variance (AMOVA) among groups of the forkbeard based on mtDNA cyt b.
Table 5.
Population pairwise FST values for cyt b sequences of the forkbeard.
Fig 6.
Frequency distributions of the number of pairwise nucleotide differences between cytochrome b haplotypes from forkbeard populations.
Parameter values for the mismatch distributions are given in Table 6.
Table 6.
Parameters for the mismatch distribution and the neutrality tests of the forkbeard cyt b haplotypes.