Family: Tetrabothriidae Fuhrmann, 1908

Tetrabothrius Rudolphi, 1819

Tetrabothrius sp.

Location: small intestine.

Locality: Bariloche, Rio Negro Province (Argentina).

Reference: Kreiter & Semenas (1997).

Tetrabothrius argentinum Szidat, 1964

Other host: L. maculipennis, L. cirrocephalus .

Location: small intestine.

Localities: Puerto Quequén, Tandil, Buenos Aires Province, Mar del Plata (Argentina).

Reference: Szidat (1964), Labriola & Suriano (2001). Tetrabothrius cylindraceus (Rudolphi, 1819)

Other hosts: Larus scoresbii Traill, Larus audouinii Payraudeau

Location: small intestine.

Localities: Buenos Aires and Santa Fe Province (Argentina). Lakes: Huillincho, Yelcho, Tagua Tagua, Llanquihue, Rupanco, Caburga Lake, Yaldad, Chiloé Island (Chile).

References: Szidat (1964), Torres et al. (1991(a), 1992, 1993), Roca et al. (1999).