Description of two new species and phylogenetic placement of recent taxonomic novelties in the Chilean endemic genus Miersia (Gilliesieae, Allioideae, Amaryllidaceae)

Abstract: Two new species in the Chilean endemic genus <em>Miersia</em> (Gilliesieae, Allioideae, Amaryllidaceae) are introduced: <em>M. stellata</em> and <em>M. raucoana</em>. A morphological description, distribution map, illustration, and the assessment of their conservation status are provided for each new taxon, along with an updated key to all species in <em>Miersia</em>. Additionally, analyses of DNA sequences were performed to inquire the evolutionary affinities of both new species and the recently described, <em>M. putaendensis</em>, within Gilliesieae phylogenetic framework. Data from multiple single-copy nuclear genes, as well as the inclusion of <em>Trichlora</em> and <em>Schickendantziella</em>, are necessary to corroborate the tribe’s phylogeny and reassess its generic classification. Dataset description: Two phylip alignment files were uploaded: 1) Miersia_nov_ITS_3.0.phy, includes sequences of nrDNA ITS (nrITS) region, and 2) Miersia_nov_cpDNA_3.0.phy, includes concatenated sequences of two chloroplast (cpDNA) markers, <em>trnL-F</em> and <em>rbcL</em>. Sequences were aligned using MAFFT v.1.4.0. Three *.bestTree.tre files for 1) nrITS, 2) cpDNA, and 3) concatenated dataset of all loci (nrITS, <em>trnL-F</em>, <em>rbcL</em>). All were inferred using RAxML-NG v.1.1.0 (Kozlov et al. 2019), GTR+Γ as the model of molecular evolution (--model GTR+G), and partitioned by locus. nrITS and cpDNA analyses were performed conducting 50 tree searches using 25 random and 25 parsimony-based starting trees to pick the best-scoring topology (--tree pars{25},rand{25}), and the concatenated analysis included 100 tree searches using 50 random and 50 parsimony-based starting trees (--tree pars{50},rand{50}). Also, the respective boostrap trees (*.bootstraps.tre) were uploaded for each analysis. Likelihood bootstrap analyses were conducted in RAxML-NG v.1.1.0 with 1,000 pseudoreplicates (--bs-trees 1000). We also uploaded two Nexus files which correspond to sequence data from Escobar et al. (2020, Bot. J. Linn. Soc. 194: 84–99), considering that these are currently not available in TreeBase.