Gwynia capsula

Gwynia capsula is a very small to minute brachiopod (maximally long), currently known from the east Atlantic (France, Belgium, British Isles), but which occurred during the Pleistocene in what is now Norway. It has a translucent, whitish, purse-shaped shell with relatively large, wide-spaced pits (or punctae). It lives attached to stones or shells (fragments) in between large grains of sand. Like in all brachiopods, it filters food particles, chiefly diatoms and dinoflagellates. "Gwynia capsula" harbors a small number of larvae inside a brood pouch, but it has separate sexes, unlike also very small and pouch brooding "Argyrotheca" and "Joania", which are hermaphrodite.