Land Flatworms (Platyhelminthes: Tricladida) in Remnants of Deciduous Forest in the Northeast Region Of Southern Brazil

Abstract

Land flatworms show high endemism due to their restricted mobility. In southern Brazil, land flatworm communities have been found mainly in areas of ombrophilous forests. Thus, this study documents land planarian species composition in remnants of deciduous seasonal forest in the northeast region of southern Brazil. Direct, diurnal samplings reveal the occurrence of 26 species of land flatworms, of which one belongs to the subfamily Rhynchodeminae and the others to the subfamily Geoplaninae. The Rhynchodeminae genus Rhynchodemus Leidy 1851 and the following Geoplaninae genera occurred: CephaloflexaCarbayo & Leal-Zanchet, 2003, Choeradoplana Graff, 1896, Imbira Carbayo et al., 2013, IssocaFroehlich, 1955, LuteostriataCarbayo, 2010, Obama Carbayo et al., 2013, Paraba Carbayo et al., 2013, Pasipha Ogren & Kawakatsu, 1990 and XerapoaFroehlich, 1955, besides the collective group Pseudogeoplana Ogren & Kawakatsu, 1990. The genus Obama had the highest species richness (S=6), followed by Paraba (S=4) and Pasipha (S=3). Eighteen species were recorded exclusively in one of the two study areas, and eight species occurred in both sites. The known distribution of Luteostriata abundans (Graff, 1899), Choeradoplana iheringiGraff, 1899, Obama ficki (Amaral & Leal-Zanchet, 2012), Imbira guaiana (Leal-Zanchet & Carbayo, 2001) and Pasipha hauseri (Froehlich, 1959) is increased. Results emphasize the relevance of expanding taxonomic studies on land flatworms and including more study areas in southern Brazil.