Thyrsopteris
genus of plants
Thyrsopteris is a genus of tree fern. It contains a single living species, Thyrsopteris elegans, endemic to the Juan Fernandez Archipelago off the coast of Chile.
The oldest records of the genus are the species Thyrsopteris cretacea and Thyrsopteris cyathindusia which were described from the Burmese amber of Myanmar, dating to the Cenomanian of the Cretaceous period, around 99 million years ago. Other fossil species include Thyrsopteris antiqua from the Upper Cretaceous of Chile and Thyrsopteris shenii from the Paleogene of King George Island, Antarctica A thyrsopterid rachis is also known from the Upper Cretaceous of Japan.
Description
T. elegans is perhaps unique in having fronds which are quadripinnate or even pentapinnate (leaflets are the fifth order of branching).
Taxonomy
Thyrsopteris is the only genus in the family Thyrsopteridaceae in the Pteridophyte Phylogeny Group classification of 2016 (PPG I). Alternatively, the genus may be placed in the subfamily Thyrsopteridoideae of a more broadly defined family Cyatheaceae, the family placement used in Plants of the World Online as of November 2019.
Begin with the source’s own compact description: “Thyrsopteris” is genus of plants. The dossier treats that line as a proposition to test through Thyrsopteris, genus and plants, not as a finished interpretation.
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The date and method of observation matter as much as the stated conclusion, especially where classification or consensus has changed. The source revision retrieved here is dated Nov 1, 2025. The linked authority identifier is Q15814215. None of the 0 selected statements returned an explicit reference. The first chronological checks are 2016 and 2019.
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This entry incorporates text from “Thyrsopteris” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.