The identity of Drimia purpurascens, with a new nomenclatural and taxonomic approach to the “Drimia undata” group (Hyacinthaceae = Asparagaceae subfam. Scilloideae)

The identity of Drimia purpurascens, a name usually synonymised to the African D. elata, is clarified. Morphological data in the protologue allow identification of the former with the Mediterranean D. undata (Urginea undulata), which is usually treated as belonging to Charybdis, a genus morphologically and molecularly separated from both Drimia s.str. and Urginea. However, Charybdis is considered to be illegitimate and hence unavailable for use, and when treated as different from Drimia and Urginea, the name Squilla might be applied. A binding decision was requested from the Nomenclature Committee for Vascular Plants on whether Scilla and Squilla are sufficiently alike to be confused. In the meantime, Drimia is here accepted to include, among others, two morphologically distinct aggregates: the “D. undata group” and the “D. maritima group”. The present contribution focusses on the former, in which three species are recognised that show clear morphological and biogeographical differences. Two specific names are revived: D. purpurascens (for D. undata) and D. serotina (for D. tazensis), the latter established as a new combination. Furthermore, a new species (D. palaestina sp. nov.) is described for the easternmost Mediterranean populations referred to D. undata. Similarly, one additional combination, D. secundiflora, is effected in the “Drimia maritima group”. Nomenclatural types (including 3 new lectotypes, 2 new neotypes and 1 new epitype) are indicated, and synonyms are shown for each accepted taxon. The taxonomic treatment for the “D. undata group” including chromosome numbers, phenology, habitats, distribution, and conservation status is presented. An identification key is also reported.This work was partly supported by H2020 Research and Innovation Staff Exchange Programme of the European Commission, project 645636: “Insect-plant relationships: insights into biodiversity and new applications” (FlyHigh), the research project AICO-2019-003 from Generalitat Valenciana, and the grants ACIE18–03, UAUSTI18–02 and UAUSTI19-08 from University of Alicante