Parasites of the stout razor clam Tagelus plebeius (Psammobiidae) on the Argentinean coast, Southwest Atlantic Ocean

VÁZQUEZ, N.N.; ITUARTE, CRISTIÁN F; NAVONE, GRACIELA T.; CREMONTE , FLORENCIA

JOURNAL OF SHELLFISH RESEARCH

NATL SHELLFISHERIES ASSOC

Año: 2006 vol. 25 p. 877 - 886

0730-8000

This work describes the parasites and their respective pathologies in the stout razor clam, Tagelus plebeius (Lightfoot, 1786) (Psammobiidae) from Argentinean coasts, representing the first report on a histopathological survey for this species. Specimens of T. plebeius  were collected in the Mar Chiquita coastal lagoon (37°46?S, 57°27?W) (n = 104 dissected under stereomicroscope, n= 28 histologicaly sectioned, including most organs, and microscopically examined) and from the mouth of the Quequén Salado River (38°56?S, 60º33?W) (n =14 dissected under stereomicroscope). Tagelus plebeius was found acting as first intermediate host for two trematode species of the families Fellodistomidae and Gymnophallidae, by hosting sporocysts mainly in gonad and digestive gland that results in the replacement of host tissues and as a second intermediate host by hosting a gymnophallid metacercaria. Tagelus plebeius is also housing a larval spirurinae nematode encapsulated by haemocytes, and two ciliatre scpecies without apparent host reaction. The finding of two ciliate species, the gymnophallid cercaria and metacercaria, and the larval nematode represent the first records for the host. The only digenean previously recorded in T. plebeius was a felloditomid cercaria. The parasites previously recorded, a larval cestode and a protozoa of the genus Perkinsus, all from Norwestern Atlantic coast, were not found in the present study. The Southwestern Atlantic populations of this clam seem to be devoid of serious pathogens in the study area.