Hydrobia ulvae. Smallest specimen 2mm high, largest 6mm high. Top row; males (have penes), middle row; females or immature (lack penes), lowest row; juveniles. All from a population with deep shell sutures at the mouth of the Dee Estuary, Cheshire.
Hydrobia ulvae. Smallest specimen 2mm high, largest 6mm high. Top row; males (have penes), middle row; females or immature (lack penes), lowest row; juveniles. All from a population with deep shell sutures at the mouth of the Dee Estuary, Cheshire.
Hydrobia ulvae. Smallest specimen 2mm high, largest 6mm high. Top row; males (have penes), middle row; females or immature (lack penes), lowest row; juveniles. All from a population with deep shell sutures at the mouth of the Dee Estuary, Cheshire.
