The grass tribe Andropogoneae (Poaceae—Panicoideae) includes several important crops such as maize, sugarcane, and sorghum, and dominates the tropical grasslands of the world. We present here a plastome phylogeny of the tribe with the largest sample of genera to date (about 73%), including 65 newly assembled plastomes, together with a broad biogeographic analysis of Andropogoneae. Major relationships found in previous phylogenetic studies were confirmed here, with most nodes having higher resolution and support, including those of the backbone of the tree, which had been a major problem in previous phylogenies of the tribe. Our dated tree suggests that Andropogoneae diverged from Arundinelleae in the Early Miocene, while the “core Andropogoneae” clade originated in the Late Miocene. The tribe originated in East Asia, but intercontinental dispersal has been common, with many independent dispersal events to Africa and the New World. Based on the plastome phylogeny, we propose here a new classification of Andropogoneae as most of its previously accepted subtribes are not monophyletic. Our classification comprises 14 subtribes, 92 genera, and ∼1224 species. About 90% of the Andropogoneae species could be assigned to a subtribe, which represents a major step toward clarification of the taxonomy of the tribe. The remaining taxa were placed
A global phylogeny of grammitid ferns (Polypodiaceae) and its systematic implications
Abstract Grammitidoideae are the largest subfamily in Polypodiaceae and contain about 911 species. Progress has been made in understanding the overall phylogeny and generic boundaries in the light of recent molecular works. However, the majority of species, especially Asian species, and some critical type species of genera remain unsampled . In this study, a dataset of six plastid markers of 1003 (112 new) accessions representing ca. 412 species of Grammitidoideae including the type species of Ctenopterella , Grammitis , Moranopteris , Radiogrammitis , and Themelium , was assembled to infer a phylogeny. Our major results include: (1) the type species of Grammitis is successfully sequenced using a next‐generation sequencing technique and is resolved in Grammitis s.str. as expected; (2) Ctenopterella is found to be polyphyletic and a new clade consisting of C. khaoluangensis is resolved as sister to Tomophyllum ; (3) the type species of Ctenopterella is resolved in a clade sister to the C. lasiostipes clade; (4) Oreogrammitis is found to be polyphyletic and three clades outside of the core Oreogrammitis are identified containing O. subevenosa and allies, O. orientalis , and O. beddomeana (+ O. cf. beddomeana ); (5) Prosaptia is found to be paraphyletic with P. nutans being sister to a clade containing the rest of Prosaptia and Archigrammitis ; (6) the intergeneric and major relationships within the Asia‐Pacific clade are well resolved and strongly supported except for a few branches; (7) extensive cryptic speciation is detected in the Asia‐Pacific clade; and (8) based on the polyphyly of Ctenopterella we describe three new genera, Boonkerdia , Oxygrammitis , and Rouhania , for species formerly in Ctenopterella ; because the type species of Grammitis belongs to Grammitis s.str., we describe five new genera, Aenigmatogrammitis , Grammitastrum (stat. nov.), Howeogrammitis , Nanogrammitis , and Thalassogrammitis for species formerly in Grammitis s.l. A key to the 35 Old‐World genera is given, a taxonomic treatment is presented, and the morphology of all new genera is shown with either a color plate and/or a line drawing.
more »
« less
- Award ID(s):
- 2101884
- PAR ID:
- 10444803
- Date Published:
- Journal Name:
- TAXON
- ISSN:
- 0040-0262
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
more » « less
Abstract incertae sedis pending additional molecular data. The new subtribes Chrysopogoninae and Rhytachninae are described herein. Our plastome trees also indicate that several Andropogoneae genera are para‐ or polyphyletic and require additional studies to define their circumscriptions. -
more » « less
Molecular systematic studies of the anthozoan class Octocorallia have revealed widespread incongruence between phylogenetic relationships and taxonomic classification at all levels of the Linnean hierarchy. Among the soft coral taxa in order Malacalcyonacea, the family Alcyoniidae and its type genus
Alcyonium have both been recognised to be highly polyphyletic. A recent family-level revision of Octocorallia established a number of new families for genera formerly considered to belong to Alcyoniidae, but revision ofAlcyonium is not yet complete. Previous molecular studies have supported the placement ofAlcyonium verseveldti (Benayahu, 1982) in family Cladiellidae rather than Alcyoniidae, phylogenetically distinct from the other three genera in that family. Here we describe a new genus,Ofwegenum gen. nov. to accommodateO. verseveldti comb. nov. and three new species of that genus,O. coronalucis sp. nov. ,O. kloogi sp. nov. , andO. colli sp. nov. , bringing the total number of species in this genus to four.Ofwegenum gen. nov. is a rarely encountered genus so far known from only a few locations spanning the Indian and western Pacific Oceans. We present the morphological characters of each species and use molecular data from both DNA barcoding and target-enrichment of conserved elements to explore species boundaries and phylogenetic relationships within the genus. -
Mikó, István (Ed.)Abstract The millipede family Xystodesmidae includes 486 species distributed primarily in temperate deciduous forests in North America and East Asia. Species diversity of the family is greatest in the Appalachian Mountains of the eastern United States, with 188 species. Although the group includes notable taxa such as those that are bioluminescent and others that display Müllerian mimicry, producing up to 600 mg of cyanide, basic alpha-taxonomy of the group is woefully incomplete and more than 50 species remain undescribed in the Appalachian Mountains alone. In order to establish a robust phylogenetic foundation for addressing compelling evolutionary questions and describing species diversity, we assembled the largest species phylogeny (in terms of species sampling) to date in the Diplopoda. We sampled 49 genera (out of 57) and 247 of the species in the family Xystodesmidae, recollecting fresh material from historical type localities and discovering new species in unexplored regions. Here, we present a phylogeny of the family using six genes (four mitochondrial and two nuclear) and include pivotal taxa omitted from previous studies including Nannaria, Erdelyia, taxa from East Asia, and 10 new species. We show that 6 of the 11 tribes are monophyletic, and that the family is paraphyletic with respect to the Euryuridae and Eurymerodesmidae. Prior supraspecific classification is in part inconsistent with the phylogeny and convergent evolution has caused artificial genera to be proposed. Subspecific classification is likewise incongruent with phylogeny and subspecies are consistently not sister to conspecifics. The phylogeny is used as a basis to update the classification of the family, diagnose monophyletic groups, and to inform species hypotheses.more » « less
-
The infraorder Astacidea, comprising marine clawed lobsters and freshwater crayfish, include some of the most recognizable decapod crustaceans, many being harvested commercially for human consumption and aquaculture. While molecular analyses have elucidated relationships among extant lineages, the composition and placement of several fossil groups within Astacidea remain poorly resolved, with several conflicting phylogenetic hypotheses and taxonomic classifications being proposed in previous works. Among these controversial groups, Erymoidea have variably been placed in Astacidea or Glypheidea, a largely extinct infraorder of predominantly pseudochelate marine lobsters. Cladistic relationships of Stenochiroidea have also been problematic, having been regarded as ancestral to freshwater crayfish (Astacida) or extant marine lobsters (Nephropidae). Failure to reach a consensus regarding these groups can be at least partially attributed to the prevalence of morphological convergence and limited taxon sampling. To clarify evolutionary relationships among fossil and extant taxa, a Bayesian phylogenetic analysis of morphological and molecular data (mitochondrial genes: 12S, 16S and COI; nuclear genes: 18S, 28S and H3) was performed that included extensive taxon sampling of all currently recognized families of Astacidea as well as representatives of several potential sister groups. To overcome error introduced by homoplasy, relationships among extant taxa, as revealed by previous molecular analyses, were used to identify morphological characters with potentially robust phylogenetic signal. The resulting phylogeny places erymids within Glypheidea and supports a sister relationship between Astacidea and Glaessnericarididae. Stenochiroidea was found to be polyphyletic, with most genera forming a clade sister to Nephropidae; Pseudastacus is moved to Protastacidae, which resolves as the sister taxon to freshwater crayfish. The relationships among living and fossil taxa presented here provide new insight into the origins and evolutionary histories of the major lineages of marine clawed lobsters and freshwater crayfish.more » « less
-
Phylogenetic relationships within many lineages of the phylum Nematoda remain unresolved, despite numerous morphology-based and molecular analyses. We performed several phylogenomic analyses using 286 published genomes and transcriptomes and 19 new transcriptomes by focusing on Trichinellida, Spirurina, Rhabditina, and Tylenchina separately, and by analyzing a selection of species from the whole phylum Nematoda. The phylogeny of Trichinellida supported the division of Trichinella into encapsulated and non-encapsulated species and placed them as sister to Trichuris. The Spirurina subtree supported the clades formed by species from Ascaridomorpha and Spiruromorpha respectively, but did not support Dracunculoidea. The analysis of Tylenchina supported a clade that included all sampled species from Tylenchomorpha and placed it as sister to clades that included sampled species from Cephalobomorpha and Panagrolaimomorpha, supporting the hypothesis that postulates the single origin of the stomatostylet. The Rhabditina subtree placed a clade composed of all sampled species from Diplogastridae as sister to a lineage consisting of paraphyletic Rhabditidae, a single representative of Heterorhabditidae and a clade composed of sampled species belonging to Strongylida. It also strongly supported all suborders within Strongylida. In the phylum-wide analysis, a clade composed of all sampled species belonging to Enoplia were consistently placed as sister to Dorylaimia + Chromadoria. The topology of the Nematoda backbone was consistent with previous studies, including polyphyletic placement of sampled representatives of Monhysterida and Araeolaimida.more » « less
- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/tax.12992
