Suborder Ophiurina Müller & Troschel, 1840 sensu O’Hara et al. 2017

Diagnosis

Genital papillae on adradial genital plate form an arm comb (secondarily lost in Astrophiuridae) at the distal end of the plate. Cluster of teeth on ventral part of dental plate. Lateral arm plates generally much more fragile than in Ophiomusina . Many strongly paedomorphic taxa in which arm combs and oral tooth clusters may be reduced or absent. Second tentacle pore outside of mouth slit or opening into it but never concealed.