THE FIRST SUBTERRANEAN FRESHWATER PLANARIANS FROM NORTH AFRICA, WITH AN ANALYSIS OF ADENODACTYL STRUCTURE IN THE GENUS DENDROCOELUM (PLATYHELMINTHES,

Abstract: The paper describes the first species of freshwater planarians collected from subterranean localities in northern Africa, represented by three new species of Dendrocoelum Örsted, 1844 from Tunisian springs. Each of the new species possesses a well-developed adenodactyl, resembling similar structures in other species of Dendrocoelum, notably those from southeastern Europe. Comparative studies revealed previously unreported details and variability in the anatomy of these structures, particularly in the composition of the musculature. An account of this variability is provided, and it is argued that the anatomical structure of adenodactyls may provide useful taxonomic information