What is "gwynia"

Gwynia capsula is a very small to minute brachiopod (maximally long), currently known from the east Atlantic (France, Belgium, Netherlands, 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 stone or shell(fragment)s 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.