Taxonomic novelties and phylogenetic insights on Gilliesieae (Allioideae, Amaryllidaceae) from Chile

Tribe Gilliesieae (Allioideae, Amaryllidaceae) comprises bulbous plants characterized by their zygomorphic flowers and a distribution restricted to Chile, Argentina, Peru, and Bolivia. The main objective of this article is to introduce four new species of Gilliesieae recently discovered in central Chile, two belonging to Gilliesia (G. reflexa, G. taguataguensis) and two to Miersia (M. nahuelbutensis, M. subandina). Three of the new species are exclusively distributed in the O’Higgins Region, while the fourth has been recorded in the Biobío and La Araucanía regions.

In addition, the new species were placed within the phylogenetic context of the tribe to explore their evolutionary relationships. For this purpose, plastid DNA regions (rbcL and trnL-F) and the nuclear ribosomal DNA spacer (ITS) were amplified and sequenced, and the resulting sequences were analyzed together with molecular data from previous studies. The phylogenetic results support the inclusion of the new species within Gilliesia and Miersia, respectively, and support a previously suggested broad circumscription of Gilliesia, encompassing Ancrumia, Gethyum, and Solaria.

We provide morphological descriptions, a distribution map, field images, illustrations, and conservation assessments for the new species, as well as an updated key to all species of Gilliesieae.