title: First record of the microsporidian parasite Steinhausia mytilovum in Mytilus sp. (Bivalvia: Mytilidae) from France.
abstract: Steinhausia mytilovum is a globally distributed microsporidian parasite which infects the oocytes of the blue mussels Mytilus edulis and M. galloprovincialis. Despite the intensive monitoring effort made on mussel populations, the parasite has not previously been reported in France. We report herein on the occurrence of S. mytilovum in Mytilus sp. from 1 cultured and 2 natural populations on the northern coast of France, thus extending the parasite's known distribution northwards. We also report on the observation in 1989 of S. mytilovum in M. galloprovincialis from the Golfe de Fos area in the Mediterranean Sea (South of France). S. mytilovum was observed in the European hybrid zone between M. edulis and M. galloprovincialis, which therefore renders the exact taxonomic status of the infected hosts unknown. The prevalence of the parasite was low, which suggests that its effect on mussel populations was probably limited.
authors.affiliation: Laboratoire Conchylicole de Bretagne, IFREMER, Station de la Trinité-sur-Mer, 12 rue des résistants, BP 26, 56470 La Trinité-sur-Mer, France. comtet@sb-roscoff.fr
authors.forename: Thierry
authors.initials: T
authors.lastname: Comtet
authors.forename: Céline
authors.initials: C
authors.lastname: Garcia
authors.forename: Yvette
authors.initials: Y
authors.lastname: Le Coguic
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Joly
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000469:parasitology*; D005260:Female; D005602:France; D005843:Geography; D006652:Histological Techniques; D016815:Microsporea / Q000166:cytology*; D009865:Oocytes / Q000473:pathology*; D015995:Prevalence