Phylogeography of the common pandora <i>Pagellus erythrinus</i> in the central Mediterranean Sea: sympatric mitochondrial lineages and genetic homogeneity

<div><p>ABSTRACT</p><p>The distribution of the genetic diversity and the population structure of <i>Pagellus erythrinus</i> were analysed using mitochondrial control region sequences and cytochrome <i>b</i> restriction profiles in a total of 128 and 508 individuals, respectively, that were collected from 15 sampling sites in the central Mediterranean Sea and from one site in the Atlantic Ocean. No population genetic structure was detected within the central Mediterranean and thus, the commonly recognized transition zones in the area do not seem to affect population connectivity. The comparison between the Mediterranean samples and the single Atlantic sample suggests weak differentiation between the two basins. Three mitochondrial lineages were identified, each including individuals from almost every sampling site. The haplotype and nucleotide diversity values, mismatch distribution and demographic parameters indicate that the sympatry of these lineages can be ascribed to a period of isolation followed by genetic divergence, population expansion and secondary contact, all of which are likely to be associated with climatic oscillations that occurred during the middle and late Pleistocene.</p></div

Species trees estimated with concatenation and coalescent approaches.

<p>Panel A: ML and BI trees of concatenated dataset (RAG1 and cyt <i>b</i> sequences); bootstrap values (>70%) and Bayesian posterior probabilities (>0.7) are reported. Sl-Arno, Ss-Arno, Ss-Vipava, Tm-Tiber idicate specimens whose cyt <i>b</i> and RAG1 sequences were available in GenBank (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0060392#pone.0060392.s007" target="_blank">Table S4</a>). Specimen Ss22 showing a <i>S. lucumonis</i>-like nuclear sequence, and Sl14 showing both mitochondrial and nuclear <i>R. rubilio</i>-like sequences, are boxed. Panel B: Phylogeny estimated with *BEAST; posterior probabilities shown for all nodes.</p

Scatterplot representing the pattern obtained by partial least square (PLS) analysis of shape (GM) and genetic (PCOA axes) data.

<p>Splines show shapes relative to the extremes of the y-axes. Specimen Ss22 and Sl14 are indicated by arrows.</p

Classification tree obtained from the CRT analysis.

<p>NSLL: number of scales of the lateral line; NRAF : number of rays of the anal fin; NRPF : number of rays of the left pectoral fin. Rr: <i>R. rubilio</i>; Ss: <i>S. squalus</i>; Sl: <i>S. lucumonis</i>; Tm: <i>T. muticellus</i>.</p

Landmarks used for Geometric morphometrics analysis of external shape.

<p>(1) Snout tip; (2) nostril; (3) beginning of scales coverage on the dorsal outline; (4) centre of the eye; (5) posterior extremity of the premaxillar; (6) insertion of the operculum on the ventral lateral profile; (7) beginning of the lateral line; (8) posterior extremity of the operculum; (9) superior and (10) inferior insertions of the pectoral fin; (11) anterior and (12) posterior insertions of the dorsal fin; (13) superior and (17) inferior insertions of the caudal fin; (14) superior and (16) inferior insertion of the caudal peduncle: (15) posterior body extremity; (18) posterior and (19) anterior insertion of the anal fin; (20) anus; (21) anterior insertion of the pelvic fin.</p

Details on the sampling sites in Tiber River basin and on number of individuals collected. Sl stands for <i>Squalius lucumonis</i>, Ss for <i>Squalius squalus</i>, Tm for <i>Telestes muticellus</i>, Rr for <i>Rutilus rubilio</i>, respectively.

<p>Details on the sampling sites in Tiber River basin and on number of individuals collected. Sl stands for <i>Squalius lucumonis</i>, Ss for <i>Squalius squalus</i>, Tm for <i>Telestes muticellus</i>, Rr for <i>Rutilus rubilio</i>, respectively.</p