HYSTEROTHYLACIUM FABRI (NEMATODA, RAPHIDASCARIDIDAE) IN MULLUS SURMULETUS (PERCIFORMES, MULLIDAE) AND URANOSCOPUS SCABER (PERCIFORMES, URANOSCOPIDAE) FROM THE MEDITERRANEAN

Raphidascarididae are among the most abundant and widespread parasitic nematodes in the marine environment. Knowledge about the life-cycle of most raphidascaridid species is still poorly known and information about their distribution and host range is lacking in many geographical areas, as well as the taxonomy of several species. A study of larval and adult stages of Hysterothylacium fabri (Rudolphi, 1819) Deardorff & Overstreet, 1980 (Nematoda: Raphidascarididae) infecting the striped goatfish Mullus surmuletus Linnaeus, 1758 (Mullidae) and the Mediterranean stargazer Uranoscopus scaber Linnaeus, 1759 (Uranoscopidae) from Ionian Sea (central Mediterranean) has been carried out by combining light and scanning electron microscopy observations and molecular analyses through PCR-RFLP and sequencing of the ITS rDNA gene. Results indicate that U. scaber and M. surmuletus represent suitable definitive and intermediate/paratenic hosts of H. fabri respectively in the Mediterranean and highlight the importance of combining genetic and morphological data to study the taxonomy and epidemiology of parasites widely distributed in different fish species and aquatic ecosystems.