Girardia
Diagnostic description:
High triangular shaped head, sometimes truncated. Absence of seminal vesicle or presence of the bifid nonmuscular type. Absence of diaphragm. The musculature of the inner circular muscules of the bursal canal is surrounded by longitudinal or intermingled fibres. Numerous testes that can be ventral, dorsal or occupying all the space between the dorsal and the ventral surface. The pharynx is usually pigmented.
Distribution:
Tasmania, Australia (doubtful) and America. Introduced species of Girardia are present in Europe and East Asia.
Ecology:
Freshwater.