Resurrection of Acanthocanthopsis Heegaard, 1945 (Copepoda, Poecilostomatoida, Chondracanthidae), Parasitic on Tetraodontiform Fishes

The genus Acanthocanthopsis Heegaard, 1945 is considered valid based on examination of newly collected specimens of the type-species, A. quadrata Heegaard, 1945, from 2 tetraodontiform hosts (Pisces) captured in Australian waters. Pseudochondracanthus chilomycteri (Thomson, 1889) is transferred to Acanthocanthopsis. This latter genus can be differentiated from other chondracanthid genera by a combination of characters that include processes on the cephalosome, one pair of modified legs, a trunk bearing processes, a caudal ramus tipped with a small spine, a mandible armed with over 100 teeth on both margins, and a maxilliped claw with an accessory tooth in the female, as well as a vestigial first leg in the male. An amended diagnosis of Acanthocanthopsis is also provided.