Abstract
Fifteen species of Lejeunea and three species of Taxilejeunea (Lejeuneaceae, subfam. Lejeuneoideae) occurring in Misiones, Argentina are described and illustrated: Lejeunea cancellata Nees & Mont., L. filipes Spruce, L. flava (Sw.) Nees, L. geophila Spruce, L. grossitexta (Steph.) E.Reiner & Goda, L. laetevirens Nees & Mont., L. lepida Lindenb. & Gottsche, L. monimiae (Steph.) Steph., L. phyllobola Nees & Mont., L. ptosimophylla C.Massal., L. puiggariana Steph., L. quinqueumbonata Spruce, L. setiloba Spruce, L. tapajosensis Spruce, L. trinitensis Lindenb., Taxilejeunea obtusangula (Spruce) A.Evans, T. pterigonia (Lehm. & Lindenb.) Schiffn. and T. terricola (Spruce) Steph. Five new synonyms (Lejeunea flava (Sw.) Nees [syn. nov.: L. symphoreta Spruce], L. lepida Lindenb. & Gottsche [syn. nov.: L. cladobola Spruce] and L. phyllobola Nees & Mont. [syn. nov.: L. cephalandra Spruce, L. polycephala Spruce and L. brittoniae (A.Evans) Grolle]) and four lectotypifications (L. lepida Lindenb. & Gottsche, L. monimiae (Steph.) Steph., L. phyllobola Nees & Mont. and L. quinqueumbonata Spruce) are proposed. Keys for identification of the species are also provided.