New synonyms, morphological characterizations and national records for three neotropical Lejeunea species, including comments on distribution and ecology, are presented. Lejeunea cristulata (Steph.) M.E.Reiner & Goda (= L. resupinata [Steph.] Steph., syn. nov.) is newly recorded for Venezuela, Peru and Bolivia. Lejeunea diversicuspis Spruce (= L. megalantha Spruce, syn. nov.; = L. erostrata M.E.Reiner & Goda, syn. nov.) is until now only known from type materials collected by Richard Spruce at the Rio Negro and is new to Venezuela. Lejeunea laeta (Lehm. & Lindenb.) Lehm. & Lindenb. (= Lejeunea diversistipa Lindenb. & Gottsche, syn. nov.) is newly recorded for Venezuela, Peru and Bolivia, and is newly lectotypified. A list of new names in Lejeunea published since the appearance of the World Checklist of Hornworts and Liverworts is presented.