title: Turbellarian black spot disease in bluespine unicornfish Naso unicornis in New Caledonia, caused by the parasitic turbellarian Piscinquilinus sp.
abstract: Turbellarian black spot disease is described in a bluespine unicornfish Naso unicornis (Perciformes, Acanthuridae) collected from the wild off Nouméa, New Caledonia, South Pacific. Each cyst contained a whitish worm, 2 to 4 mm in length, which was able to swim freely in seawater. Cyst walls consisted of fibrous tissue with a scattering of melanocytes. Worms had 2 eyespots at the anterior end, a pharynx at the posterior end and a largely undeveloped reproductive system. They were identified as Piscinquilinus sp. (= Ichthyophaga sp.), a genostomatid turbellarian. The disease spread within 2 wk from a single infected fish to 3 other unicornfish in the same tank, in spite of copper sulphate and diluted seawater treatment; however, other fish from several families kept in the same tank were not infected, suggesting specificity of these parasites. Praziquantel injections into the infected fish eliminated the infection. Other cases of turbellarian infections are reported from 7 fish species off New Caledonia; prevalence is very low (0.3%).
authors.affiliation: Equipe Biogéographie Marine Tropicale, Unité Systématique, Adaptation, Evolution (CNRS, UPMC, MNHN, IRD), Institut de Recherche pour le Développement, BP A5, 98848 Nouméa Cedex, New Caledonia. justine@ird.nc
authors.forename: Jean-Lou
authors.initials: JL
authors.lastname: Justine
authors.forename: Philippe
authors.initials: P
authors.lastname: Leblanc
authors.forename: Florent
authors.initials: F
authors.lastname: Keller
authors.forename: Robert J G
authors.initials: RJ
authors.lastname: Lester
mesh_terms: D000818:Animals; D000871:Anthelmintics / Q000627:therapeutic use; D005393:Fish Diseases / Q000188:drug therapy / Q000469:parasitology* / Q000473:pathology*; D006374:Helminthiasis, Animal / Q000188:drug therapy / Q000469:parasitology* / Q000473:pathology*; D009510:New Caledonia; D011223:Praziquantel / Q000627:therapeutic use; D014419:Turbellaria / Q000502:physiology*
chemical_list: D000871:Anthelmintics; D011223:Praziquantel