Morphological and molecular identification of the fish-borne metacercaria of Ascocotyle (Phagicola) longa Ransom, 1920 in Mugil liza from Argentina

Abstract

This is the first report of Ascocotyle (Phagicola) longa Ransom, 1920 (Digenea: Heterophyidae) in Argentina reported by morphological and molecular studies. The metacercaria was found encysted in myotomal musculature, heart and mesentery of the mullet Mugil liza (Pisces: Mugilidae) from Samborombon Bay. We provide a morphological description of the metacercaria and we identified it using species-specific primers for A. (Phagicola) longa. This worldwide parasite has been reported as one of the causative agents of heterophyiasis, an emerging fish-borne disease of humans, contracted by the consumption of raw mullets. The discovery of A. (Phagicola) longa in Argentina represents a warning about the potentially great impact of this parasite on public health.