A new species of Gieysztoria (Platyhelminthes, Rhabdocoela) from Argentina and a kinship analysis of South American species of the genus

Abstract

This study describes a new species of Gieysztoria found in lentic environments in Argentina. Gieysztoria falx sp. n. appears to be closely related to G. therapaina and G. intricata, and is differentiated principally by the presence of two strongly developed pincer-shaped spines of the cuticular stylet. A preliminary analysis of the phylogeny among the South American species of this genus is undertaken, and the monophyly verified. This study constitutes the first approach to interpreting these relationships.