Taiwan; endemic, surviving only in Menghuan Pond, Yangmingshan National Park, Taipei
Water
freshwater
Maximum size
25 cm
Temperature
15–25°C
pH
5.5–7
Hardness
1–8 dGH
Care level
expert
Lighting
Medium light; CO2 helpful
Care
Taiwan quillwort is the only quillwort native to Taiwan and is now known from a single mountain pond. It is listed as critically endangered, threatened by the pond drying out and land plants moving in. Its genome was the first quillwort genome to be sequenced in detail. In the wild it grows rooted in the muddy bottom of shallow water, fully submerged in the wet winter and emerging as the pond shrinks in the dry summer. Leaves are slender and about 5–25 cm long, rising from a three- to four-lobed corm. There is almost nothing recorded about growing it in aquariums. Treat it like other quillworts: a fine, rich substrate, moderate light and soft water, with the corm planted at the surface. Water figures are our estimate, not from the sources. Wild plants must never be collected. Only cultivated plants of known origin should be traded. Sources: Wikipedia (en.wikipedia.org/wiki/Isoetestaiwanensis); Wikipedia (en.wikipedia.org/wiki/Isoetes); Wikipedia, List of freshwater aquarium plant species. Checked October 2026.
Breeding
Reproduces by spores formed in the leaf bases (large and small spores on separate leaves). Propagation in captivity is specialist work and not documented for aquariums.
Compatibility and tank mates
Slow and delicate: keep with small, peaceful fish and shrimp in a cool to subtropical tank. Diggers will uproot it.
Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.
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