Abstract
A new tetramerid nematode, Microtetrameres urubitinga n. sp., is described from specimens recovered from the proventriculus of the great black-hawk, Buteogallus urubitinga (Aves: Accipitridae), from Formosa Province, Argentina. The males of the new species are characterized by having spicules unequal (length ratio of spicules 1:3.8–5.9) and dissimilar in shape (right spicule with a simple tip, left spicule with a symmetrical bifurcated tip), caudal papillae arranged asymmetrically (two pairs precloacal and two pairs postcloacal) and cloacal lips highly protruded forming a tube. The gravid females are permanently coiled clockwise or counterclockwise in a spiral and having a tail tapering gradually to a sharp point, with a cuticular fold. This is the first nominal species of Microtetrameres (Travassos, 1915TRAVASSOS L. 1915. Sobre as especies brazileiras de genero Tetrameres Creplin. 1846 (Nota previa). Brazil Med 29: 297-298.) described parasitizing birds from Argentina. The relationship between the diet of B. urubitinga and the low prevalence of M. urubitinga n. sp. is discussed.
Key words
Accipitridae; Argentina; Buteogallus urubitinga; Microtetrameres urubitinga n. sp.; Tetrameridae