The Ordovician conodont genus Pygodus

Two evolutionary branches of Pygodus are recognized and discussed. The new species Pygodus lunnensis and P. protoans erinus are proposed and described in detail. It is suggested that P. anserinus did not evolve directly from P. serra but from P. protoanserinus sp. n. Two new subzones within the Eoplacognthus suecicus Zone are proposed: the Pygodus lunnensis and P. anitae Subzone.