Molecular phylogenetic analyses reveal multiple long-distance dispersal events and extensive cryptic speciation in Nervilia (Orchidaceae), an isolated basal Epidendroid genus

Frontiers in Plant Science, Journal Year: 2025, Volume and Issue: 15

Published: Feb. 20, 2025

Introduction The terrestrial orchid genus Nervilia is diagnosed by its hysteranthous pattern of emergence but nested among leafless myco-heterotrophic lineages in the lower Epidendroideae. Comprising ca. 80 species distributed across Africa, Asia and Oceania, remains poorly known plagued vague overlapping circumscriptions, especially within each a series taxonomically intractable complexes. Prior small-scale, exploratory molecular phylogenetic analyses have revealed existence cryptic species, little otherwise understood origin, scale timing biogeographic spread, or palaeoclimatic factors that shaped ecology given rise to contemporary patterns occurrence. Methods Here, we sample widely throughout generic range, including 45 named taxa multiple accessions referable several widespread ‘macrospecies’, as well material equivocal identity probable undescribed status, for first time enabling an evaluation taxonomic boundaries at both sectional level. Using nuclear ( ITS ) plastid matK , trnL-F sequence data, conduct (maximum parsimony Bayesian inference) ancestral area analysis infer relationships resolve origin colonisation routes. Results strongly supported monophyletic, are three sections. However, number flowers inflorescence other floral characters poor indicators affinity. Dated supports Africa Early Oligocene, with spread eastwards occurring Late Miocene, plausibly via Gomphotherium land bridge when it woodland savanna ecosystems. Discussion Taxonomic radiation last 8 million years ties dramatic Himalayan-Tibetan Plateau uplift associated intensification monsoon. Multiple long-range migrations appear occurred thereafter, colonised Malesia Oceania from Pliocene onwards. bulk diversity relatively recent, potentially explaining ubiquity speciation, which leaves numerous overlooked unnamed. Widespread disjunct pairs hint high mobility continents, extinction history climate-induced vicariance. Persistent challenges highlighted.

Language: Английский

Complete chloroplast genome of eight Phaius (Orchidaceae) species from China: comparative analysis and phylogenetic relationship

BMC Plant Biology, Journal Year: 2025, Volume and Issue: 25(1)

Published: Jan. 10, 2025

Phaius Lour. (Collabieae, Orchidaceae) is a small genus consisting of about 45 species, with highly ornamental and medicinal values. However, the phylogenetic relationship among Calanthe s. l. has been debated based on morphological molecular data. The complete chloroplast (cp) genome widely used as useful marker for resolving problems, while few genomic data was available. Therefore, cp genomes eight species were sequenced characterized in detail to provide better understanding its phylogenetics investigated exhibited conserved quadripartite structures varied lengths ranging between 157,997 bp 158,735 bp. overall GC content these ranged 36.82 36.97%. Gene annotation revealed 136 genes all genomes, which 21 duplicated inverted regions 15 introns. Comparative analysis stable sequence identity greater variation single-copy regions, alongside notable differences at LSC/IRb IRb/SSC junctions, well number SSRs. CDS from 49 Collabieae indicated that together other two P. philippinensis hainanensis, clustered into monophyletic clade divided subclades strong supports. Additionally, it also supported should be five genera supports, including s., Cephalantheropsis, Styloglossum, Phaius, Preptanthe. It first report six (P. columnaris, mishmensis, takeoi, tonkinensis, wallichii wenshanensis) comparatively analyzed flavus tancarvilleae. provided comprehensive investigation various features implications, structure, codon usage, repeat sequences, IR boundaries, DNA polymorphisms, reconstruction. suggested treated independent genera. concept new Paraphaius not confirmed by here. intergeneric alliance group could understood more

Language: Английский

Whole chloroplast genome sequence and phylogenetic analysis of Calanthe discolor (Orchidaceae)

Mitochondrial DNA Part B, Journal Year: 2024, Volume and Issue: 9(10), P. 1345 - 1349

Published: Oct. 2, 2024

The orchid

Language: Английский