Polyzygia Guerich (Ostracoda) in the Devonian of Asturias and Leon (Spain)

The Devonian ostracode genus Polyzygia Gürich has been defined anew and its systematical position has been revaluated. It is considered as a thlipsurid (bas-relief sculpture) metacope (tripartite hinge, contact groove). Eight species (one new, one with open nomenclature) and two subspecies are described, all from the Devonian of the central part of the Cantabrian Mountains, provinces of Asturias and León, Spain. The existence of pores and of a micro-scale reticulation is established. An opinion is given concerning the calcification of the valves, and the known geographical and stratigraphical distribution is discussed.