A new species of Megalophallus (Digenea: Microphallidae) from the clapper rail, other birds, and the littoral isopod Ligia baudiniana

Megalophallus reamesi n.sp. infected the clapper rail, ruddy turnstone, black-bellied plover, and the isopod Ligia baudiniana. This precociously developed digenean occurred in the mid-Florida Keys, Florida, and in Pine Cay, Turks and Caicos, British West Indies, but not in numerous other examined localities from New York to Texas. It is most similar in body size (1.0–1.6 vs 1.0–1.1 mm) and structure of its copulatory organ to M. diodontis Siddiqi and Cable, 1960, but its copulatory organ has 23–39 micropapillae rather than 12–19, the species has rudimentary intestinal ceca rather than short fully developed ones, and an isopod rather than a portunid crab serves as the second intermediate host. The encysted metacercaria, occurring in the hemocoel of the isopod, was typically encapsulated with host connective tissue incorporating several host chromatophores.