Contracaecum microcephalum (Rudolphi, 1809)

Host: Ardea alba egretta (cited as Casmerodius albus egretta). SI: esophagus, stomach and small intestine. Lo: Leales, Tucumán Province 1; La Plata Zoological Garden, Buenos Aires Province 2. Material deposited: CH–N–FML 18171. References: Schuurmans Stekhoven (1951) 1; Boero et al. (1972a) 2.

Host: Ardea cocoi . SI: esophagus, stomach and small intestine. Lo: La Plata Zoological Garden, Buenos Aires Province. Reference: Boero et al. (1972a).

Host: Nycticorax nycticorax . SI: esophagus, stomach and small intestine. Lo: Uribelarrea 1 and La Plata Zoological Garden, La Plata 2, Buenos Aires Province. References: Boero & Led (1971) 1; Boero et al. (1972a) 2.