Phylogenetic systematics of Juncaceae

Area of Science:

• Plant Taxonomy
• Phylogenetics
• Molecular Systematics

Background:

• The genus Juncus s.l. (rushes) is paraphyletic, necessitating taxonomic revision.
• A 2022 classification proposed new genera but faced criticism regarding monophyly and reliance on older morphological data.

Purpose of the Study:

• To assess the monophyly of newly proposed genera in Juncaceae using extensive molecular data.
• To provide a more robust phylogenetic framework for Juncaceae classification.

Main Methods:

• Utilized the Angiosperms 353 probe set for target capture.
• Sequenced hundreds of nuclear and plastid loci.
• Performed phylogenetic analyses to evaluate generic monophyly.

Main Results:

• Most proposed genera were found to be monophyletic.
• Juncinella was nested within Boreojuncus, indicating a need for revision.
• Juncinella capitata may represent a distinct monotypic genus.
• Australojuncus cyperoides and Verojuncus chlorocephalus were misplaced based on morphology.

Conclusions:

• Proposed taxonomic revisions to address identified non-monophyletic groups.
• Highlighted the need for further research, especially for South African annual Juncus s.l. taxa.