Aspidosiphon (Paraspidosiphon) planoscutatus Murina, 1968  

Murina (1968) described this species based on two specimens collected in the Red Sea in a marine habitat with unusual abiotic conditions (e.g., high salinity and temperature and low oxygen). Similar to A. steenstrupii, it differs in the lack compressed bidentate hooks Cutler & Cutler (1989) questioned whether this is a real difference and pointed to the need for verification of the species based on a larger sample. Nevertheless, they retained the species A. planoscutatus as valid because of its exclusive distribution in an unusual habitat.