New Geoplaninae (Platyhelminthes: Tricladida) with an accessory musculoglandular organ

VERÓNICA N. BULNES; GRAU, J.H.

Simposio; International symposium of flatworm biology; 2015

Oxford University

The testes are placed differently among the planarians in general. In most planarians the testes and efferent ducts are placed at the ventral side of the body. Exceptionally in land planarians of the subfamily Geoplaninae (South America, 800 spp.) and the tribe Eudoxiatopoplanini (Southern Islands, 1 sp.) testes are located dorsally; while in the tribe Anzoplanini (Subantartic Islands, 2 spp.) testes are located dorsoventrally. Herein we describe and discuss the phylogenetic position of a land planarian from Chile which bears an exceptional combination of morphological characteristics. The land planarian specimen is about 21 mm long and presents a dark brown dorsal coloration. While bearing dorsally located testes, the copulatory apparatus is supplemented with a sophisticated musculoglandular organ and a series of glandular tampon-like muscular folds. Glando-muscular organs such as adenodactyls and adenomuralia are typical morphological characteristics of land planarians of the subfamily Rhynchodeminae, namely the tribes Caenoplanini, Anzoplanini and Eudoxiatopoplanini of the Australian regions. Furthermore, the land planarian specimen was collected in the valdivian temperate rainforest in southern Chile (40° 68` S, 72° 91` W), an ecoregion of high biogeographical interest in the context of Gondwanan connections. While morphological similarities of the land planarian fauna between the Chilean and the Notogeic regions have been briefly mentioned in the past, no musculoglandular organs of this type have been previously described in other Geoplaninae species.