# Wood ferns of East Asia and Malesia
[East Asia](https://www.edgepedia.org/east-asia) and Malesia hold the global center of diversity of the wood-fern family [Dryopteridaceae](https://www.edgepedia.org/dryopteridaceae), the largest fern family with slightly more than 2,100 species, nearly 20% of extant fern diversity.[1](https://doi.org/10.1016/j.pld.2024.07.010) The family's richness peaks in temperate East Asia, where the two largest regional genera, *Dryopteris* (wood ferns) and *Polystichum* (shield ferns), reach their greatest numbers of species, and in tropical mountains.[1](https://doi.org/10.1016/j.pld.2024.07.010) Southeast Asia alone is estimated to hold about 4,500 pteridophyte species, more than one third of the world's fern diversity.[2](https://websites.rbge.org.uk/thaiferns/PDF_docs/BNMNS2012_Rare-Pterid-Asia1.pdf)
| Key fact | Value |
|---|---|
| Global family size | Slightly more than 2,100 species, ~20% of fern diversity[1](https://doi.org/10.1016/j.pld.2024.07.010) |
| Species in China | 493 (260 endemic) per Flora of China; 505 including subspecies and varieties in a 2024 statistical catalog[3](https://www.iplant.cn/foc/pdf/Dryopteridaceae.pdf) • [4](https://www.biodiversity-science.net/EN/abstract/abstract8634.shtml) |
| *Dryopteris* center of diversity | Sino-Himalaya: 204 species, about 60% of the genus[5](https://pmc.ncbi.nlm.nih.gov/articles/PMC12455213/) |
| *Polystichum* | Ca. 500 species worldwide; Old World taxa are ca. 80% of the genus[6](https://bmcecolevol.biomedcentral.com/articles/10.1186/s12862-016-0626-z) |
| Mount Kinabalu fern flora | 544 species in 138 genera and 36 families[7](https://pmc.ncbi.nlm.nih.gov/articles/PMC12064423/) |
| Current classification | Seven subfamilies and 24 genera (2024 revision)[1](https://doi.org/10.1016/j.pld.2024.07.010) |
| Southeast Asian ferns DNA-sequenced | Less than 6% before 2024[8](https://www.nature.com/articles/s41597-024-04161-8) |
## Composition and generic diversity
Four genera account for about 80% of the family's species: *[Ctenitis](https://www.edgepedia.org/ctenitis)*, *Dryopteris*, *Elaphoglossum*, and *Polystichum*.[3](https://www.iplant.cn/foc/pdf/Dryopteridaceae.pdf) Two of these, *Dryopteris* and *Polystichum*, have their diversity centers in East Asia.[3](https://www.iplant.cn/foc/pdf/Dryopteridaceae.pdf) *Polystichum* is probably the third largest fern genus in the world with ca. 500 species, occurring on all continents except [Antarctica](https://www.edgepedia.org/antarctica), with its highest diversity in Southwest China and adjacent regions.[6](https://bmcecolevol.biomedcentral.com/articles/10.1186/s12862-016-0626-z) *Dryopteris* is ranked as the third largest genus in Dryopteridaceae and the fourth largest among all ferns in a 2025 treatment,[9](https://doi.org/10.3897/phytokeys.269.163893) though its global species count is reported inconsistently across sources (see below).
Molecular phylogenetics has redrawn generic limits in the family. Six satellite genera (*Acrophorus*, *Acrorumohra*, *Diacalpe*, *Dryopsis*, *Nothoperanema*, and *Peranema*) were found embedded within a paraphyletic (a group that excludes some of its descendants) *Dryopteris* and merged into it.[10](http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=110995) A 2024 revision based on plastome phylogenomics and morphology recognized seven subfamilies and 24 genera, describing four new subfamilies (Ctenitidoideae, Lastreopsidoideae, Pleocnemioideae, Polystichopsidoideae), and a new genus, *Pseudarachniodes*.[1](https://doi.org/10.1016/j.pld.2024.07.010) Within *Polystichum*, a multilocus phylogeny of 177 accessions resolved two strongly supported subgenera, *P. subg. Polystichum* and *P. subg. Haplopolystichum*.[6](https://bmcecolevol.biomedcentral.com/articles/10.1186/s12862-016-0626-z)
## By the numbers
China is the best-documented national flora. [Flora of China](https://www.edgepedia.org/flora-of-china) records ten genera and 493 species of Dryopteridaceae in the country, of which 260 are endemic; the largest subfamily, Dryopteridoideae, has six genera and 459 species (244 endemic) in China.[3](https://www.iplant.cn/foc/pdf/Dryopteridaceae.pdf) A 2024 statistical catalog gives a slightly higher count of 505 species including subspecies and varieties, making Dryopteridaceae the largest fern family in China, ahead of [Athyriaceae](https://www.edgepedia.org/athyriaceae) (323) and [Polypodiaceae](https://www.edgepedia.org/polypodiaceae) (280).[4](https://www.biodiversity-science.net/EN/abstract/abstract8634.shtml) The same catalog lists *Polystichum* (209 species) and *Dryopteris* (176) as China's two largest fern genera, with endemics concentrated in Dryopteridaceae (257 species), *Polystichum* (140), and *Dryopteris* (61).[4](https://www.biodiversity-science.net/EN/abstract/abstract8634.shtml)
Provincial richness falls along a southwest-to-north gradient: the five richest provinces for lycophytes and ferns are Yunnan (1,365 species), Sichuan (875), Guizhou (838), Guangxi (785), and Taiwan (779).[4](https://www.biodiversity-science.net/EN/abstract/abstract8634.shtml) Within *Dryopteris*, the Sino-Himalaya region (western China, eastern Himalaya, northern Burma) harbors 204 species, about 60% of the genus, while only 30 species are listed for Vietnam and 34 for nearly the whole of Indochina.[5](https://pmc.ncbi.nlm.nih.gov/articles/PMC12455213/) Regional *Polystichum* counts include ca. 50 species in the Himalaya, 32 in [Japan](https://www.edgepedia.org/japan-epzdpsev89), and ca. 40 in Vietnam.[6](https://bmcecolevol.biomedcentral.com/articles/10.1186/s12862-016-0626-z)
## Endemism and island and mountain hotspots
Endemism concentrates at mountain scale. Globally, 58% of fern species richness occurs in eight principally montane hotspots that together cover just 7% of Earth's land area, based on more than 800,000 georeferenced records of nearly 8,000 species.[11](https://doi.org/10.1111/jbi.14076) Hotspots of fern richness and endemism show disproportionately high ecological variation, and the persistence of ancient lineages in areas of long-term climatic stability helps explain exceptional endemism in Malesia.[11](https://doi.org/10.1111/jbi.14076)
In China, 260 of 493 Dryopteridaceae species (about 53%) are endemic,[3](https://www.iplant.cn/foc/pdf/Dryopteridaceae.pdf) and the southwest of the country, where the richest provinces lie, holds the concentration of endemic *Polystichum* and *Dryopteris*.[4](https://www.biodiversity-science.net/EN/abstract/abstract8634.shtml) Narrow-range taxa follow the same pattern: of narrowly distributed Asian pteridophyte taxa enumerated toward a red-list assessment, 577 occur in Southeast Asia, 215 in East Asia, and 101 in [South Asia](https://www.edgepedia.org/south-asia).[2](https://websites.rbge.org.uk/thaiferns/PDF_docs/BNMNS2012_Rare-Pterid-Asia1.pdf) Single mountains can hold range-restricted species: *Dryopteris pycnolepis* was described in 2025 from a small population on Mt. Hoàng Liên, northern Vietnam, at 2,860 m in montane broadleaved evergreen forest.[5](https://pmc.ncbi.nlm.nih.gov/articles/PMC12455213/)
[Mount Kinabalu](https://www.edgepedia.org/mount-kinabalu) in Sabah, Borneo, illustrates the island-mountain effect. The Kinabalu region, including Mt Tomboyukon and the Crocker Range, harbors 544 fern species in 138 genera and 36 families, with fern diversity peaking between 1,500 and 2,000 m elevation.[7](https://pmc.ncbi.nlm.nih.gov/articles/PMC12064423/) The mountain reaches about 4,100 m and was uplifted within the last 6 million years, making recent geological uplift one of the mechanisms behind its diversity.[7](https://pmc.ncbi.nlm.nih.gov/articles/PMC12064423/)
## Biogeographic history and pathways
Ancestral-range reconstruction for the family identifies the Americas as the most probable ancestral area, with long-distance dispersal throughout the family's history.[1](https://doi.org/10.1016/j.pld.2024.07.010) For the polystichoid clade (*Cyrtomium*, *Phanerophlebia*, *Polystichum*), a well-sampled phylogenetic analysis suggests the group may have originated in East Asia during the Eocene, with three [Paleogene](https://www.edgepedia.org/paleogene) transoceanic dispersals between the Old and [New Worlds](https://www.edgepedia.org/new-worlds) compatible with a boreotropical migration scenario: one for *Phanerophlebia* in the late Eocene (34 Ma) and two for *Polystichum* near the Eocene–[Oligocene](https://www.edgepedia.org/oligocene) boundary (30 Ma and 28 Ma).[12](https://www.kiphub.com/paper/61e504a389a8141a63f6261a) Earlier chloroplast DNA work showed that *Phanerophlebia* did not arise from *Cyrtomium*; both are convergent descendants of different progenitor groups within *Polystichum*, and the Asiatic *Cyrtomium* is more closely related to temperate New World *Polystichum* than to neotropical *Phanerophlebia*.[13](https://doi.org/10.1073/pnas.85.8.2589)
## How it compares with other regions
The Americas hold the largest share of the family's genera, 17 of 24, followed by Eurasia with 12, Africa with 9, and [Australasia](https://www.edgepedia.org/australasia) with 9.[1](https://doi.org/10.1016/j.pld.2024.07.010) The New World center is *Elaphoglossum*, while East Asia centers on *Dryopteris* and *Polystichum*.[1](https://doi.org/10.1016/j.pld.2024.07.010) Southeast Asia alone, with an estimated 4,500 pteridophyte species, exceeds one third of global fern diversity.[2](https://websites.rbge.org.uk/thaiferns/PDF_docs/BNMNS2012_Rare-Pterid-Asia1.pdf)
Different hotspots can be rich in species yet share little evolutionary history. The fern floras of Mount Kinabalu and the Bolivian Andes share only 10–20% common ancestors despite showing surprisingly consistent elevational patterns of species richness, family representation, and life forms.[7](https://pmc.ncbi.nlm.nih.gov/articles/PMC12064423/)
## Recent developments
The 2024 plastome-phylogenomic classification is the largest recent change, replacing earlier subfamilial schemes with seven subfamilies and 24 genera and adding the genus *Pseudarachniodes*.[1](https://doi.org/10.1016/j.pld.2024.07.010) Species discovery continues at a steady pace in the region: *D. pycnolepis* from northern Vietnam (2025),[5](https://pmc.ncbi.nlm.nih.gov/articles/PMC12455213/) *D. ningqiangensis* from Ningqiang County, Shaanxi (type collected August 2024 at 1,280 m, a hybrid with a probable tetraploid *D. bissetiana* mother and *D. gymnophylla* as father),[9](https://doi.org/10.3897/phytokeys.269.163893) two further Chinese hybrid taxa, the triploid *D. parabissetiana* and the diploid *D. ×tiantangzhaiensis*,[14](https://doi.org/10.1002/tax.13116) and *D. gaoligongensis* from southwest China, a new species in the roughly 12-species *D. sect. Diclisodon*.[15](https://www.integrativebiology.ac.cn/pd/EN/Y2022/V44/I02/181)
Reference data has also improved. A 2024 DNA barcode dataset sequenced 1,496 expert-identified Asian fern samples covering 956 species across 152 genera and 34 families, from Malaysia, the Philippines, [Taiwan](https://www.edgepedia.org/taiwan-landform), and Vietnam, adding 292 species sequenced for the first time.[8](https://www.nature.com/articles/s41597-024-04161-8) Before this, less than 6% of Southeast Asian ferns had been DNA-sequenced despite the region harboring around one third of the world's fern species.[8](https://www.nature.com/articles/s41597-024-04161-8)
## References
1. [A revised classification of Dryopteridaceae based on plastome phylogenomics and morphological evidence, with the description of a new genus, Pseudarachniodes](https://doi.org/10.1016/j.pld.2024.07.010)
2. [Rare and Threatened Pteridophytes of Asia 1. An Enumeration of Narrowly Distributed Taxa](https://websites.rbge.org.uk/thaiferns/PDF_docs/BNMNS2012_Rare-Pterid-Asia1.pdf)
3. [Dryopteridaceae, Flora of China](https://www.iplant.cn/foc/pdf/Dryopteridaceae.pdf)
4. [Diversity and distribution of lycophytes and ferns in China](https://www.biodiversity-science.net/EN/abstract/abstract8634.shtml)
5. [Dryopteris pycnolepis, a new fern species from northern Vietnam, with miscellaneous notes on Dryopteris sect. Splendentes (Dryopteridaceae)](https://pmc.ncbi.nlm.nih.gov/articles/PMC12455213/)
6. [Using a multilocus phylogeny to test morphology-based classifications of Polystichum (Dryopteridaceae)](https://bmcecolevol.biomedcentral.com/articles/10.1186/s12862-016-0626-z)
7. [Phylogenetic diversity sheds light on the evolution of the unique fern flora of Mount Kinabalu, Borneo](https://pmc.ncbi.nlm.nih.gov/articles/PMC12064423/)
8. [A DNA barcode reference of Asian ferns with expert-identified voucher specimens and DNA samples](https://www.nature.com/articles/s41597-024-04161-8)
9. [Dryopteris ningqiangensis, a new species of Dryopteridaceae from Shaanxi, China](https://doi.org/10.3897/phytokeys.269.163893)
10. [Dryopteris in Flora of China @ efloras.org](http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=110995)
11. [Mountains, climate and niche heterogeneity explain global patterns of fern diversity](https://doi.org/10.1111/jbi.14076)
12. [A well-sampled phylogenetic analysis of the polystichoid ferns (Dryopteridaceae)](https://www.kiphub.com/paper/61e504a389a8141a63f6261a)
13. [Chloroplast DNA evolution and systematics of Phanerophlebia (Dryopteridaceae) and related fern genera](https://doi.org/10.1073/pnas.85.8.2589)
14. [Two new Dryopteris taxa originated from distantly related congeners in China](https://doi.org/10.1002/tax.13116)
15. [A revision of Dryopteris sect. Diclisodon (Dryopteridaceae) based on morphological and molecular evidence with description of a new species](https://www.integrativebiology.ac.cn/pd/EN/Y2022/V44/I02/181)
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*Topic: Encyclopedia › Life and health › Plants and algae › Ferns and lycophytes › Other leptosporangiate fern families › Wood and shield ferns (Dryopteridaceae) › Regional occurrence of wood and shield ferns*
*Initially written Sep 17, 2026 · Edited: Oct 11, 2026; Oct 15, 2026; Oct 21, 2026*
*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*
License: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license