Delving deeper into the phylogenetics of the herbaceous bamboos (Poaceae, Bambusoideae, Olyreae): evaluation of generic boundaries within the Parodiolyra/Raddiella clade uncovers a new genus

Abstract

The present study aims to expand the knowledge of phylogenetic relationships in Olyrinae, a subtribe of herbaceous bamboos (Poaceae: Bambusoideae: Olyreae). Our focus is on Parodiolyra and Raddiella, two historically related genera that, with their sister Diandrolyra, form one of the four main lineages in the subtribe. Previous phylogenetic analyses suggested that Parodiolyra is not monophyletic, but its taxonomic boundaries and its relationship with Raddiella remain uncertain due to low sampling. We increased the taxon sampling and sequenced five regions of the nuclear and plastid genomes for this lineage and other representatives of Olyreae. We used maximum parsimony, maximum likelihood, Bayesian inference and coalescence analysis. Our results corroborate the paraphyly of Parodiolyra, with P. micrantha sister to a clade including the remaining Parodiolyra and Raddiella. All remaining Parodiolyra form a well-supported clade, but Raddiella had conflicting resolutions, being either monophyletic or not. Thus, based on phylogenetic and morphological evidence, we here recircumscribe Parodiolyra, transferring P. micrantha and P. colombiensis to the new genus Taquara (described here). Regarding Raddiella, sampling is still not comprehensive and does not allow a decision on to its taxonomic status to be made at this time. Inclusion of other phreatophytic species may be crucial to resolve the problem of conflicting topologies.

Phylogenetics of Piresia (Poaceae: Bambusoideae) reveals unexpected generic relationships within Olyreae with taxonomic and biogeographic implications

“…Oliveira & al. (2020) and Wang & al. (2020) with Buergersiochloinae as sister to the Parianinae‐Olyrinae clade.…”

“…Olyreae is distinguished by the presence of weakly lignified culms, simple vegetative branching, absence of differentiated culm leaves and outer ligules, unisexual spikelets (at least functionally) and an annual or seasonal flowering pattern (Judziewicz & al., 1999; R.P. Oliveira & al., 2014, 2020; Soreng & al., 2017; Ferreira & al., 2019; I.L.C. Oliveira & al., 2020).…”

“…Olyrinae is the most diverse subtribe of the three and currently includes 20 genera, of 24 total in the Olyreae, and approximately 89 species (of 124 in the tribe) that occur from Mexico and the West Indies to Argentina and Brazil, with one also reaching Africa (R.P. Oliveira & al., 2014, 2020; Clark & Oliveira, 2018; Ruiz‐Sanchez & al., 2019; Carvalho & al., 2020; I.L.C. Oliveira & al., 2020).…”

“…Oliveira & al., 2014, 2020; Clark & Oliveira, 2018; Ruiz‐Sanchez & al., 2019; Carvalho & al., 2020; I.L.C. Oliveira & al., 2020). The Olyrinae have been distinguished from the Buergersiochloinae and Parianinae mainly by the absence of fimbriae on the apex of the leaf sheaths (Judziewicz & Clark, 2007; R.P.…”

“…The subtribe has been recovered as a well‐supported monophyletic group in different molecular phylogenetic studies (Kelchner & Bamboo Phylogeny Group, 2013; R.P. Oliveira & al., 2014, 2020; Wysocki & al., 2015; Soreng & al., 2017; Wang & al., 2018; Ruiz‐Sanchez & al., 2019; I.L.C. Oliveira & al., 2020; Wang & al., 2020), using different taxon sampling and different markers including plastomes.…”