Table 1. Sample collection details.

Code	Locality	Coastal region	Country	Sampling date	Sample size
RB	El Tesón, Ría de Ribadeo	Rías Altas	Spain	October 2017	50
BA	Barallobre		Spain	October 2017	50
PO	Campelo, Ría de Pontevedra	Rías Baixas	Spain	November 2017	50
CA	Cangas, Ría de Vigo		Spain	February 2018	50
AV	Ria de Aveiro	North coast of Portugal	Portugal	November 2017	49
OB	Lagoa de Óbidos		Portugal	December 2017	50
AL	Ria Formosa, Algarve	Gulf of Cadiz	Portugal	October 2017	50
VE	Venice Lagoon	Adriatic Sea	Italy	December 2017	50