Roderosignus Michalík, 1977

Diagnosis : Straight double grooves, joining under an angle roughly 72°. The course of grooves is nearly parallel with the surface of substratum, reaching about 0,001—0,05 mm deep. The grooves are 0,05—0,1 mm wide, 1—6 mm long. The grooves occur on a relatively soft substratum (as the surface of valves of large brachiopods), overgrown with commensalic organisms, the shells of these small organisms are obviously destructed.