Re-establishment of species from synonymies based on DNA barcoding and phylogenetic analysis using Diplopterygium simulans (Gleicheniaceae) as an example

PLoS One. 2017 Mar 15;12(3):e0164604. doi: 10.1371/journal.pone.0164604. eCollection 2017.

Abstract

Because synonymy treatment traditionally relies on morphological judgments, it usually causes many problems in species delimitation and in the biodiversity catalogue. For example, Diplopterygium simulans, which belongs to the Gleicheniaceae family, has been considered to be synonymous with D. glaucum or D. giganteum based mainly on the morphology of its pinna rachis and blade. In the absence of molecular evidence, these revisions remain doubtful. DNA barcoding, which is considered to be a powerful method for species-level identification, was employed to assess the genetic distance among 9 members of the Diplopterygium genus. The results indicate that D. simulans is an independent species rather than a synonymy of D. glaucum or D. giganteum. Moreover, phylogenetic analysis uncovered the sisterhood of D. simulans and D. cantonense, which is supported by their geographical distributions and morphological traits. Incorrect synonymy treatment is prevalent in the characterization of biological diversity, and our study proposes a convenient and effective method for validating synonym treatments and discovering cryptic species.

MeSH terms

  • DNA Barcoding, Taxonomic*
  • DNA, Plant / genetics*
  • Ferns / genetics*
  • Phylogeny*

Substances

  • DNA, Plant

Grants and funding

Support was provided by the National Natural Science Foundation of China, 31370234, [http://www.nsfc.gov.cn/publish/portal1/] and the Shanghai Municipal Administration of Forestation & City Appearances, G142433, [http://lhsr.sh.gov.cn/]. The funders had main role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.