Remarks on Acalypha rhomboidea in Europe, with a fifth record at the continental level

Acalypha is a genus native to tropical and subtropical regions of the world and eastern North America and Asia, with some species considered as aliens in Eurasia. The European flora is reported to include four species, all occurring in Italy according to Plant of the World Online database. As part of the ongoing studies of the flora of Treviso Province (Veneto region, north-eastern Italy), we came across to a population of A. rhomboidea Raf. which represents not only the first record for Veneto and the second one for the Italian flora, but also the fifth discovery of the species out of its native range; a description of the species (the first one for Italy), ecological remarks, and a map of the European occurrences are provided.