Parasites of the stout razor clam Tagelus plebeius (Psammobiidae) from the Southwestern Atlantic Ocean

VAZQUEZ, N.; ITUARTE, C.; NAVONE, G. T.; CREMONTE, F.

JOURNAL OF SHELLFISH RESEARCH

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 about a histopathological survey for these species at the Southwestern Atlantic. Specimens of T. plebeius were collected at 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 housing two ciliate species without apparent host reaction and was found acting as first intermediate host for two digenetictrematode 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 housing a gymnophallid metacercaria. Likewise, Tagelus plebeius was found housing a larval spirurinae nematode encapsulated by haemocytes. Finding of two ciliate species, the gymnophallid cercaria and metacercaria, and the larval nematode represents the first record for the host. The only digenean previously recorded in T. plebeius was a felloditomid cercaria. The parasites previously recorded, a protozoa of the genus Perkinsus, and a larval cestode 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.