Table 1.

Genetic diversity indices of the 15 sampled sites using nine microsatellite markers.

Label	Sea	GPS coordinates		N	Nall	Ar	HS	FIS	g2
1	Ionian	40.256415	17.891478	33	5.6	3.2	0.546	0.018	0.017
2	Ionian	40.254492	17.905648	29	4.8	2.8	0.459	0.054	− 0.020
3	Adriatic	43.5575	13.612778	26	5.1	3.5	0.610	0.200***	0.015
4	Adriatic	43.7752778	15.63083333	15	3.8	2.9	0.524	0.269**	0.151**
5	Adriatic	42.453333	18.616111	35	3.9	2.4	0.429	0.228***	− 0.055
6	Adriatic	42.504733	18.753153	31	2.9	2.0	0.300	0.101	0.024
Mediterranean subsamples				169	9.6	8.2	0.632	0.348***	0.056
7	Black Sea	43.84458889	28.60035833	33	3.7	2.2	0.339	0.076***	0.080
8	Black Sea	43.412043	28.350023	31	5.0	2.7	0.419	0.048	− 0.031
9	Black Sea	42.375633	27.717717	19	4.2	2.9	0.506	0.049	− 0.028
10	Black Sea	42.331039	27.75545	11	2.9	2.4	0.424	0.048	0.093
11	Black Sea	42.186983	27.845117	2	2.1	–	0.611	0.364	–
12	Black Sea	41.18025	29.61113333	14	4.1	3.0	0.487	0.094	0.052
13	Black Sea	42.06083611	35.04415833	35	4.0	2.4	0.449	0.103***	− 0.092
14	Black Sea	44.5775	35.20333333	31	3.2	1.9	0.272	− 0.044	0.007
15	Black Sea	45.44527778	32.53277778	30	3.2	2.1	0.347	0.028	− 0.155
Black Sea subsamples				206	9.1	6.2	0.460	0.193***	− 0.010
All subsamples				375	12.9	3.9	0.441	0.109***	0.026

Results for all Mediterranean subsamples on the one hand, and Black Seas subsamples on the other hand, are in italics. Results for all subsamples are in bold.

N: number of biallelic individuals successfully genotyped, N_all: mean number of alleles per locus, A_r: allelic richness based on minimum sample size of 5 diploid individuals, removing sample 11, H_S: gene diversity, F_IS: fixation index, g₂: estimate of the identity disequilibrium.

*P-values from U test for heterozygote deficiency and for g₂ = 0 < 0.05, **p-values < 0.01 and ***p-values < 0.001.