Some Digeneans from Olrog's Gull Larus atlanticus Olrog, 1958 (Aves: Laridae) from the Bahia Blanca Estuary, Argentina

Five species of digeneans (4 Microphallidae, I Ecllinostomatidae) were recovered from a total of 85 Olrog's gulls, Larus atlanticus (dead chicks). Birds were collected from a breeding colony in the Bahia Blanca estuary, Argentina, during breeding seasons 2003 (n = 6), 2005 (n = 66), and 2006 (n = 13). Digeneans were identified as Maritrema bonaerensis, Maritrema orensensis, Odlmeria odhneri, Levinseniella cruzi, and Hintasthla escamosa. Except for M, bonaerensis, all other helminth species represent new host records, and all the digeneans reported constitute new locality records. Likely intermediate hosts for digeneans, such as Neohelice granulata (Crustacea: Decapoda), Cyrtograpsus angulatus (Crustacea: Decapoda), and Heleobia australis (Mollusca: Gastropoda), were also studied. The metacereariae of M. bonaerensis were found in the crabs N. granulata and C. angulatus, and cercariae closely resembling those of A bonaerensis, L cruzi and H. escamosa were found in the Mollusc H. australis.