Triquetrorhabdulus striatus Muller, 1974
Description: species of Triquetrorhabdulus similar to T. rugosus but with subsidiary ridges on one lateral blade.
Remarks: Some specimens are dramatically different from typical T. rugosus but they vary considerably, and weak ridges occur on some typical T. rugosus specimens (e. g. Gartner 1967 pl. 9/1).
Original description: