Redescription of Naobranchia variabilis Brian, 1924 (Siphonostomatoida: Lernaeopodidae), parasitic on the grey triggerfish Balistes capriscus Gmelin in Algerian coastal waters.

Adults of both sexes of Naobranchia variabilis Brian, 1924 (Lernaeopodidae) are described based on material collected from the gill filaments of Balistes capriscus Gmelin, caught off the coast of Algeria. This is the second species of Naobranchia Hesse, 1863 to be found in the Mediterranean and the host record is new. Morphological comparisons are made with existing descriptions of N. variabilis and it is inferred, from small variations between material from different hosts and different localities, that N. variabilis may represent a species complex. The corrugated lobes on the head of Naobranchia females are interpreted as novel structures involved with temporary attachment during feeding.