Abdominal macroparasites of commercially important flatfishes (Teleostei: Scophthalmidae, Pleuronectidae, Soleidae) in northwest Spain (ICES IXa)

This study investigated the helminth fauna of the abdominal viscera and cavity of 484 flatfishes caught in three areas off northwest Spain: the inner third of the Muros Estuary (MI), offshore from the Muros Estuary (ME) and offshore from the Arousa Estuary (AE). The following helminths were found: (a) nematodes-Cucullanus heterochrous Rudolphi, 1802, C. minutus Rudolphi, 1819, Anisakis simplex (Rudolphi, 1819), Hysterothylacium aduncum (Rudolphi, 1802), Contracaecum sp. and Capillaria gracilis Bellingham, 1840; (b) digeneans-Podocotyle atomon (Rudolphi, 1802), P. angulata (Dujardin, 1845), Macvicaria soleae (Dujardin, 1845), Derogenes varicus (Muffler, 1784), Lecithochirium rufoviride (Rudolphi, 1819), L. musculus (Looss, 1907), Synaptobothrium caudiporum (Rudolphi, 1819), Zoogonus rubellus (Olsson, 1868), Zoogonoides viviparus (Olsson, 1868), Rudolphinus crucibulum (Rudolphi, 1819), Proctoeces maculatus (Looss, 1901), Homalometron galaicus (Sanmartin, Alvarez, Quinteiro et Paniagua, 1995) and Lomasoma stephanskii Dollfus, 1960; (c) cestodes-adult Bothriocephalus barbatus Renaud, Gabrion et Pasteur, 1983, B. gregarius Renaud, Gabrion et Pasteur, 1983, Bothriocephalus sp. and Bothrimonus nylandicus (Schneider, 1902), plerocercoids of Nybelinia lingualis (Cuvier, 1817), Grillotia sp. and unidentified tetraphyllidean plerocercoids; and (d) acanthocephalans-Acanthocephaloides propinquus (Dujardin, 1845). Most of these helminths were found in more than one host species and many at more than one capture site. Of the studied hosts, Microchirus variegatus and Platichthys flesus had the richest helminth communities with 13 species. Within each capture area, the helminth faunas of the various host species were similar except P. flesus (Linnaeus), which is infected by five helminth species not present in any other host (Z. rubellus, R. crucibulum, C. minutus, Contracaecum sp. and C. gracilis). There were marked differences between the three areas (particularly between the offshore areas and MI) in the identity of the helminth species present and their abundances, so some of the parasites found may thus be useful markers of different flatfish populations in this area. (C) 2002 Elsevier Science B.V. All rights reserved.