01209nas a2200145   4500008004100000245013800041210006900179300001200248490000800260520067500268100001900943700002500962700002400987856005201011       2012                        eng d00aA new limnic species of Macrostomum (Platyhelminthes: Macrostomida) from Argentina and its muscle arrangement labeled with phalloidin0 anew limnic species of Macrostomum Platyhelminthes Macrostomida f  a197-2050 v2513 aA new species of Macrostomum from limnic environments in Argentina is described. Macrostomum platensis n. sp. differs from its congeners by the shape and length of its stylet. Moreover, the arrangement of the muscle system is described using rhodamine-labeled phalloidin. This method provides detailed information on the complex arrangement of muscles of the body wall, pharynx, head and reproductive organs. The resulting description is compared with previously published ones using the same methodological approach. The muscle arrangement may be considered for future taxonomic studies within the genus Macrostomum and might provide phylogenetically useful characters.1 aAdami, Mariana1 aDamborenea, Cristina1 aRonderos, Jorge, R.  uhttps://macrostomorpha.myspecies.info/node/4557