Table 1. Sample locations, dates, sample sizes and summary statistics by population.

Basin, A = Adriatic Sea; T = Tyrrhenian Sea; N = Number of individuals sampled; Mean N_A = mean number of alleles; R_S = allelic richness; H_E = Expected heterozygosity by population; H_O = Observed heterozygosity.

Basin	Locality	Sample label	N	Coordinates	Sampling depth (m)	Bottom depth (m)	Sampling date (month/year)	Mean NA	RS	HE	HO
A	Slovenja-Piran	SLO	35	45°33.57’N; 13°35.64’E	12	22.5	Sep-12	14.2	9.8	0.826	0.791
A	Croatia- Rijeka	RIJ	35	45°16,53'N; 14°25,07'E	40	64	Sep-12	11.5	9.6	0.763	0.728
A	Northern Adriatic Sea	NAD	35	44°49.97'N; 13°13.26'E	30	41	Sep-12	12.2	8.6	0.722	0.751
A	Croatia- Jablanac	JAB	35	44°41,47'N; 14°53,32'E	83	104	Sep-12	11.4	8.2	0.749	0.742
A	Croatia- Dugi Otok	DUG	35	43°53,07'N; 14°55,66'E	61	75	Sep-12	12.2	8.1	0.763	0.776
A	Ancona	ANC	35	43°42.20’N; 13°37.76’E	34	38.4	Sep-12	13.5	8.4	0.818	0.752
A	Pescara	PEB	35	42°54.19’N; 14°10.31’E	58	70.8	Sep-12	13.9	9.3	0.818	0.78
A	Pescara	PEA	35	42°30.19’N; 14°18.14’E	8	24.1	Sep-12	13.9	9.8	0.811	0.781
A	Boka Kotorska	KOT	50	42°25.55’N; 18°39.48’E	20	40	Jul-12	15.8	9.8	0.808	0.799
A	Montenegro	MNB	37	41°53.98’N; 19°00.96’E	75	86.7	Aug-12	13.9	9.7	0.821	0.756
A	Montenegro	MNA	35	41°49.69’N; 19°16.06’E	16	52.4	Aug-12	14	9.8	0.815	0.753
A	Bari	BAA	35	41°15.32’N; 16°34.13’E	23	31.6	Jul-12	12.8	9.2	0.809	0.758
T	Sperlonga	SPE	30	41°12.17’N; 13°23.85’E	40	80	Jun-13	12.5	10.7	0.792	0.75
A	Bari	BAB	35	41°10.60’N; 17°07.80’E	115	125.3	Jul-12	13.2	9.4	0.811	0.734
T	Castellammare del Golfo	CDG	29	38°04.81’N; 12°59.29’E	20	40	May-13	13.2	11.2	0.792	0.753