Eulejeunea crenulata Schiffn., a new synonym of Lejeunea umbilicata (Lejeuneaceae, Marchantiophyta)

Stephani (1915) proposed the transfer of Eulejeunea crenulata Schiffner (1890: 33) to Lejeunea Libert (1820: 373). However, as the combination already existed and thus not available for use, Lejeunea crenulata (Schiffn.) Stephani (1915: 784) is a later homonym of Lejeunea crenulata Mitten (1871: 415). Nonetheless, Eulejeunea crenulata remains a validly published name (Soderstrom et al . 2015). According to the recent compilation of species binomials in Lejeuneaceae published between 1884 and 1893 (Soderstrom et al . 2015), Eulejeunea crenulata is listed as a heterotypic synonym of Lejeunea patersonii (Stephani 1896: 92) Stephani (1915: 784) following Hurlimann (1993). However, this is an error as Hurlimann (1993) cited Lejeunea crenulata Mitten as a synonym of Lejeunea patersonii , following Grolle (1980), and not Eulejeunea crenulata Schiffn. ( Lejeunea crenulata (Schiffn.) Steph.). This has prompted us to revisit the true identity of Eulejeunea crenulata .