We present an updated worldwide phylogenetic classification of Poaceae with 11 783 species in 12 subfamilies, 7 supertribes, 54 tribes, 5 super subtribes, 109 subtribes, and 789 accepted genera. The subfamilies (in descending order based on the number of species) are Pooideae with 4126 species in 219 genera, 15 tribes, and 34 subtribes; Panicoideae with 3325 species in 242 genera, 14 tribes, and 24 subtribes; Bambusoideae with 1698 species in 136 genera, 3 tribes, and 19 subtribes; Chloridoideae with 1603 species in 121 genera, 5 tribes, and 30 subtribes; Aristidoideae with 367 species in three genera and one tribe; Danthonioideae with 292 species in 19 genera and 1 tribe; Micrairoideae with 192 species in nine genera and three tribes; Oryzoideae with 117 species in 19 genera, 4 tribes, and 2 subtribes; Arundinoideae with 36 species in 14 genera and 3 tribes; Pharoideae with 12 species in three genera and one tribe; Puelioideae with 11 species in two genera and two tribes; and the Anomochlooideae with four species in two genera and two tribes. Two new tribes and 22 new or resurrected subtribes are recognized. Forty‐five new (28) and resurrected (17) genera are accepted, and 24 previously accepted genera are placed in synonymy. We also provide an updated list of all accepted genera including common synonyms, genus authors, number of species in each accepted genus, and subfamily affiliation. We propose Locajonoa, a new name and rank with a new combination, L. coerulescens. The following seven new combinations are made in Lorenzochloa: L. bomanii, L. henrardiana, L. mucronata, L. obtusa, L. orurensis, L. rigidiseta, and L. venusta.

A worldwide phylogenetic classification of the Poaceae (Gramineae) III: An update

Grasses are widespread on every continent and are found in all terrestrial biomes. The dominance and spread of grasses and grassland ecosystems have led to significant changes in Earth′s climate, geochemistry, and biodiversity. The abundance of DNA sequence data, particularly chloroplast sequences, and advances in placing grass fossils within the family allows for a reappraisal of the family′s origins, timing, and geographic spread and the factors that have promoted diversification. We reconstructed a time‐calibrated grass phylogeny and inferred ancestral areas using chloroplast DNA sequences from nearly 90% of extant grass genera. With a few notable exceptions, the phylogeny is well resolved to the subtribal level. The family began to diversify in the Early–Late Cretaceous (crown age of 98.54 Ma) on West Gondwana before the complete split between Africa and South America. Vicariance from the splitting of Gondwana may be responsible for the initial divergence in the family. However, Africa clearly served as the center of origin for much of the early diversification of the family. With this phylogenetic, temporal, and spatial framework, we review the evolution and biogeography of the family with the aim to facilitate the testing of biogeographical hypotheses about its origins, evolutionary tempo, and diversification. The current classification of the family is discussed with an extensive review of the extant diversity and distribution of species, molecular and morphological evidence supporting the current classification scheme, and the evidence informing our understanding of the biogeographical history of the family.

Grasses through space and time: An overview of the biogeographical and macroevolutionary history of Poaceae

Premise Resolving relationships within order Commelinales has posed quite a challenge, as reflected in its unstable infra-familial classification. Thus, we investigated (1) relationships across families and genera of Commelinales; (2) phylogenetic placement of never-before sequenced genera; (3) how well off-target plastid data integrate with other plastid-based data sets; and (4) how the novel inferences coincide with the infra-familial classification. Methods We generated two large data sets (nuclear and plastome) by means of target sequence capture using the Angiosperms353 probe set, with additional sequences mined from publicly available transcriptomes and full plastomes. A third extended-plastid data set was considered, including all species with sequences in public repositories. Species trees were inferred under a multispecies coalescent framework from individual gene trees and also using maximum likelihood analyses from concatenated and partitioned data. Results The nuclear, plastome, and extended-plastid data sets include 52, 53, and 58 genera, respectively, and up to 290 species of Commelinales, representing the most comprehensive molecular sampling for the order to date, which includes seven never-before sequenced genera. Conclusions We inferred robust phylogenies supporting the monophyly of Commelinales and its five constituent families, and we recovered the clades Pontederiaceae-Haemodoraceae and Hanguanaceae-Commelinaceae, as previously reported. The placement of Philydraceae remains contentious. Relationships within the two largest families, Commelinaceae and Haemodoraceae, are resolved. Based on the latter results, we confirm the subfamilial classification of Haemodoraceae and propose a new classification for Commelinaceae, which includes the synonymization of Tapheocarpa in Commelina.

https://bsapubs.onlinelibrary.wiley.com/doi/pdf/10.1002/ajb2.1698

A comprehensive phylogenomic study of the monocot order Commelinales, with a new classification of Commelinaceae.

Over the past centuries and especially the last decades, herbarium collections world-wide have amassed an estimated 350 million specimens of plants and fungi, deposited in 3,400 herbaria world-wide (Soltis, 2017). Many of these specimens comprise yet-undescribed species, estimated to be around 70,000 (Bebber et al., 2010), and therefore represent a potentially highly significant contribution to taxonomy and systematics. These collections are a huge repository of botanical metadata, not only at the level of the specimen itself—with its associated collection locality, population, and associated pathogen data (Yoshida et al., 2015; James et al., 2018)—but also at the level of characters and traits such as leaf morphology (Queenborough, 2017), gene (Bieker and Martin, 2018), and genome (GGBN; Seberg et al., 2016). Analyzing this metadata permits us to look back—and perhaps even forward—in time, testing historical biological hypotheses, identifying extinct genotypes, as well as modeling past ecological processes or extrapolating future trends. Especially for plants with long generation times, it is often not feasible to observe genetic changes overmany generations in greenhouse experiments. As time series for many plant species can be amassed from global herbaria, these collections facilitate studying plants in more detail, for example to estimate mutation rates after introduction to a novel range (Exposito-Alonso et al., 2018). In fact, collectively, herbarium collections can be seen as being part of a Global Museum in which new questions can be addressed using novel combinations of disciplines that so far may not typically interact (Bakker et al., 2020), and in which digitisation of herbarium collections plays an important role (Soltis, 2017).

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Editorial: Herbarium Collection-Based Plant Evolutionary Genetics and Genomics

Cleistogenes (Orininae, Cynodonteae, Chloridoideae, Poaceae) is an ecologically important genus The phylogenetic placement of Cleistogenes and phylogenetic relationships among Cleistogenes taxa remain controversial for a long time To resolve the intra- and inter-generic relationships of Cleistogenes, the plastomes of 12 Cleistogenes taxa (including 8 species and 4 varieties), one Orinus species, 15 Triodia species, two Tripogon species, and two Aeluropus species were included in the present study All the taxa showed a similar pattern in plastome structure, gene order, gene content, and IR boundaries The number of simple sequence repeats ranged from 145 (O kokonorica) to 161 (T plurinervata and T schinzii) Moreover, 1,687 repeats were identified in these taxa, including 1,012 forward, 650 palindromic, 24 reverse, and one complement Codon usage analysis revealed that these plastomes contained 16,633 (T stipoides) to 16,678 (T tomentosa) codons Sequence divergence analysis among Cleistogenes and closely related genera identified five non-coding regions (trnS-UGA-psbZ, rpl32-trnL-UAG, trnQ-UUG-psbK, trnD-GUC-psbM, trnT-GGU-trnE-UUC) Phylogenetic analysis of complete plastomes indicated that Cleistogenes is sister to a clade composed of Orinus and Triodia, whereas it did not support the sister relationship between the recently proposed subtribe Orininae (Cleistogenes and Orinus) and Triodia The subtribe Orininae was not supported by our complete plastome data The split between Cleistogenes and Orinus-Triodia clade go back to 1401 Ma Besides, our findings suggested that C squarrosa and C songorica are the successive early diverging groups in the phylogenetic analysis The other 10 taxa are divided into two groups: a monophyletic group composed of Cleistogenes sp nov and C caespitosa var ramosa is sister to other eight Cleistogenes taxa Cleistogenes was estimated to have experienced rapid divergence within a short period, which could be a major obstacle in resolving phylogenetic relationships within Cleistogenes Collectively, our results provided valuable insights into the phylogenetic study of grass species

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Marion Martinez Martin

Papers

Plastome sequencing of a 167-year-old herbarium specimen and classical morphology resolve the systematics of two potentially extinct grass species