The interrelation between the Palaeozoic ostracodes Roundyella and Scrobicula

Abstract

The adductor-muscle scar patterns of Roundyella and Scrobicula differ greatly and do not allow us to retain these genera among the Scrobiculidae. A new family (Roundyellidae) is proposed. Both families should be assigned to independent superfamilies (Scrobiculacea and Roundyellacea). These are tentatively referred to Podocopa, due to the presence of calcified inner lamella of primitive type and (in Scrobicula) marginal pore canals. It is suggested that the marginal structures in these groups have occurred independently.