Table 1. Diversity indices within C. aestuarii and C. maenas.

Species	Region	Location	Code	N	H	h	π
C. aestuarii	Adriatic-Ionian	Marano, Italy	MA	32	18(11)	0.897	0.005
		Venice, Italy	VE	32	16(5)	0.909	0.004
		Goro, Italy	GO	32	27(18)	0.988	0.007
		Ravenna, Italy	RA	31	23(12)	0.938	0.005
		Lesina, Italy	FG	32	19(12)	0.911	0.005
		Aquatina, Italy	LE	32	15(6)	0.869	0.004
		Taranto, Italy	TA	32	14(7)	0.825	0.004
	Tyrrhenian	Naples, Italy	NAP	29	13(8)	0.892	0.021
	West Mediterranean	Cagliari, Italy	CAG	32	11(6)	0.643	0.006
		Banyuls-sur-Mer, France	BAN	17	5(1)	0.507	0.002
C. maenas	Off-shelf Europe	Seltjarnarnes, Iceland	ICE	18	1(0)	0.000	0.000
		Torshavn, Faeroe Islands	TOR	19	2(1)	0.515	0.003
	Northern Europe	Trondheim, Norway	TRO	3	3(0)	1.000	0.007
		Mongstadt, Norway	MON	22	12(5)	0.853	0.004
		Oslo, Norway	OSL	9	5(1)	0.806	0.007
		Goteborg, Sweden	GOT	15	10(3)	0.933	0.007
		Helgoland, Germany	HEL	5	2(0)	0.400	0.001
		Bremerhaven, Germany	BRE	15	7(2)	0.827	0.005
		Hoek van Holland, The Netherlands	HOE	19	7(3)	0.813	0.004
		Den Helder, The Netherlands	NET	45	17(8)	0.784	0.004
	Western Europe	Fowey, England	FOW	14	8(3)	0.890	0.005
		Isle of Wight, England	WIG	3	3(3)	1.000	0.011
		Bilbao, Spain	BIL	15	6(3)	0.648	0.003
		Betanzos, Spain	BET	14	7(4)	0.758	0.003
		Aveiro, Portugal	AVE	23	9(5)	0.795	0.004
		Cadiz, Spain	CAD	47	21(14)	0.864	0.004
		Palmones, Spain	PAL	9	8(2)	0.972	0.005

Reported are: sampling locations, number of individuals (N), number of haplotypes (H, in brackets are exclusive haplotypes), haplotype (h) and nucleotide (π) diversity.