Anatomical characters and systematics of Anodontites trapesialis (Lamarck, 1819) from South America (Mollusca, Bivalvia, Unionoida, Muteloidea)

Here is an anatomical concept of Anodontites trapesialis (Lamarck, 1819) (Bivalvia, Unionoida, Mycetopodidae) from South America. This complementary anatomical study, with a systematic interest, refers to a group of anatomical data, exclusive for this species, that may be analized to identify this wide‐ranging South‐American species, with such a variable shell. Diagnosis of A. trapesialis: trapezoid large shell, thin wall, smooth periostracus. Mantle border without tentacles, even in incurrent and excurrent canals. Presence of a fourth mantle fold well developed. Palps smooth outward, internally with relativelly large, easily view folds, and a smooth margin. Gills with transversal wide folds. Thin walled anal papilla. Evidence in some specimens of palliai cardinal muscle. Hermaphroditic gonad.

Notes

Pós Graduando, Instituto de Biociências da USP.