Embracing the pteridophyte classification of Ren‐Chang Ching using a generic phylogeny of Chinese ferns and lycophytes

Abstract

The phylogenetic relationships of pteridophytes occurring in China were reconstructed using DNA sequences of the three plastid genes, atpA, atpB, and rbcL. The sampling comprised all genera of Chinese pteridophytes-including ferns and lycophytes-with the exception of four small genera. The effort to sample all recorded families and genera in a phylogenetic framework enabled the phylogenetic relationships of all Chinese pteridophytes to be addressed for the first time in a single phylogenetic hypothesis. The results provided strong evidence to support the continuing impact of Ren-Chang Ching's integrative classification of pteridophytes. Ten out of 11 orders accepted by Ching were consistent with the phylogeny, whereas four new orders were introduced to avoid paraphyletic taxa in the leptosporangiate ferns. Of the 63 families considered by Ching, 36 families were supported by molecular data, 22 of those had the same or nearly the same circumscription, and the remaining 14 families were supported but substantially revised. Twenty-eight small families were now accepted as synonyms. A consistent pattern was observed at the generic level. Among the 223 genera considered by Ching, 133 genera were recognized by the phylogeny, although some of them were substantially changed in the context of circumscription, and 90 were now accepted as synonyms. Three endemic genera were incorporated here for the first time in DNA-based phylogenetic analyses, namely Blechnidium, Saxiglossum, and Sinephropteris, which were shown to be nested in Blechnum, Pyrrosia, and Asplenium respectively. This paper tentatively accepts 40 families and 151 genera of ferns and lycophytes occurring in China; the importance of phylodiversity of Chinese pteridophytes is also briefly discussed.

Phylogeny, historical biogeography and characters evolution of the drought resistant fern Pyrrosia Mirbel (Polypodiaceae) inferred from plastid and nuclear markers

“…In addition, infrageneric classification of Pyrrosia was always closely linked to the recognition of the segregate genera Drymoglossum and Saxiglossum 5 , 8 , 29 – 32 . Drymoglossum and Saxiglossum are currently accepted as members of Pyrrosia , which has been confirmed by phylogenetic work 33 – 35 .…”

“…Several molecular phylogenetic studies involved Pyrrosia , some of which revealed that Pyrrosia was monophyletic and Platycerium was a sister group 33 , 36 – 45 . In the most recently study, Vasques et al .…”

Tree of life for the genera of Chinese vascular plants

“…Although this relationship conflicts with the current understanding of tracheophyte relationships (e.g., Pryer et al, ), Ruhfel et al () showed recently that it was an artifact resulting from high guanine‐cytosine (GC) content. Among ferns, the backbone relationships of the early‐diverging lineages are still not fully resolved, even with much denser sampling (Liu, ). For example, the position of Equisetaceae in this study was consistent to some extent with previous studies that used similar genes (Pryer et al, ; Liu, ), but recent studies based on whole plastid genomes recovered this family as sister to a clade comprising Ophioglossaceae and Psilotaceae (e.g., Gao et al, ; Lu et al, ).…”

Large-scale phylogenomic analysis resolves a backbone phylogeny in ferns

“…However, previous research on fern phylogeny has mostly relied on plastid genes [ 10 , 12 , 13 ], some combined with a few nuclear genes [ 4 , 5 , 14 ] or morphological traits [ 5 , 11 ]. Due to incomplete lineage sorting (ILS), genes from different resources often show conflicting evolutionary patterns, especially when based on a limited number of samples, and some deep relationships in fern phylogeny remain controversial (Fig.…”