Land snails of the family Achatinidae, subfamilies Subulininae and Opeatinae, are commonly reported as alien species in European greenhouses, where they often reach high densities. These introduced species usually have tropical cosmopolitan distributions. Four of them (Opeas hannense, Allopeas clavulinum, Subulina octona, and S. striatella) are commonly reported and illustrated from greenhouses across Europe. A fifth species, Allopeas gracile, has also been reported from Europe, though from a few records only. In this paper, we report on a European colony of a sixth species, Paropeas achatinaceum, that was discovered in Austria in 2016. We provide photographic documentation for these six species with critical characters to distinguish them. In the past, at least five other alien nominal subulinine species have been reported from greenhouses in Europe. These are briefly discussed along with nomenclatural notes.