Enteric Helminths of the Shortfin Squid Illex argentinus in San Matías Gulf (Argentina) as stock discriminants.

GONZÁLEZ, R.; KROECK, M

ACTA PARASITOLOGICA

VERSITA

Lugar: Varsovia; Año: 2000 vol. 45 p. 89 - 93

1230-2821

The parasitic fauna composition of the spring-spawning (SPR) and the summer-spawning (SSS) stocks of the shortfin squid Illex argentinus was studied in San Matías Gulf, Southwest Atlantic. Seven parasite taxa were identified: 3 cestodes (Scolex polymorphus, Scolex pleuronectis and Nybelinia lingualis), and 4 nematodes (Anisakis sp., Hysterothylacium sp., Ascarophis? sp. and Pseudoterranova? sp.). Based on the prevalence (P) and mean intensity (MI) S. polymorphus [cf. Prosobothriumsp.], S. pleuronectis (Onchobothriidae) and Anisakis were the main parasites of both stocks. P and MI of these parasites were higher in SPR than in SSS. Composition, P and MI of the enteric parasitic fauna found in the subpopulations of I. argentinus in the San Matias Gulf were different from those previously reported for the other stocks of the species that occur on the Argentine continental shelf. These results provide substantial evidence for stating that the SPR and SSS stocks of I. argentinus from San Matias Gulf are biotopically isolated from the stocks that inhabit neighbouring areas of the Argentine continental shelf.