Length 26mm. Llŷn, North Wales. March 2016.
Foot elongate ellipse, sole whitish centrally, becoming yellowish towards periphery, no medial dividing line. Large foot and flat hyponotum (1) grip surface firmly and shell articulates to conform closely to uneven rock surface;
Mantle fold (2) is unobtrusive but, with aid of expanded sole, can enclose pallial cavity containing ctenidia.
Water current in enclosed pallial cavity passes through ctenidia and then as exhalent current carries sperm or ova from lateral gonopores or excreta from lateral nephridiopores, to posterior, where faecal pellets from anus (3) join the flow; to be expelled at posterior through channel formed by deflection out of hyponotum (4).

KEY ID FEATURES and similar species at: 01 Acanthochitona crinita