Cycas taitungensis

Cycas taitungensis

Cycas taitungensis is the cycad of Taiwan: in the wild it grows only on the steep slopes of two mountain areas in Taitung County, in the south-east of the island. Very close to the sago palm, this member of the genus Cycas differs from it in its longer, flatter leaves and its more massive habit. Its status divides botanists: described as a species in 1994 and accepted by The World List of Cycads, it has been placed within Cycas revoluta by POWO since a genetic study of 2022, while this site treats it as a separate species. Long sold under the wrong name Cycas taiwaniana, it is listed as Endangered in the wild. At the Jardin zoologique tropical in the south of France, it came through −6 °C (21 °F) without damage in February 2012.

Key facts about Cycas taitungensis

  • Accepted name: Cycas taitungensis C.F.Shen, K.D.Hill, C.H.Tsou & C.J.Chen (1994), accepted by The World List of Cycads (version 2026.08.15); POWO, which follows the World Checklist of Vascular Plants, places it in the synonymy of Cycas revoluta (see Taxonomy)
  • Former names: long wrongly called Cycas taiwaniana; Cycas revoluta var. taiwaniana in the sense of Schuster (1932), for cultivated plants
  • Family: Cycadaceae, order Cycadales; section Asiorientales, with Cycas revoluta alone (Hill 2008)
  • Common names: emperor sago (Hill 2008; University of Florida); prince sago (PACSOA); in Chinese tai-dong su-tie (“Taitung cycad”)
  • Natural range: Taiwan, Taitung County: two populations, on either side of the East Rift Valley, between about 300 and 900 m
  • IUCN status: Endangered (EN A3e; B1ab(v)), assessment by J. D. Bösenberg published in 2022
  • CITES and other protection: CITES Appendix II; Annex B in the European Union; both populations lie within protected areas in Taiwan
  • Documented hardiness: −6 °C (21 °F) without damage at the Jardin zoologique tropical (south of France) in February 2012, with a daytime thaw; foliage damaged from −5 to −6 °C (23 to 21.2 °F) in south-west France; survived about −16 to −13 °C (4 to 9 °F) unprotected in North Carolina, losing its leaves (see Cold hardiness)
  • Light and soil: in the wild, steep, exposed slopes on stony, free-draining soils; in cultivation, sun and a free-draining soil
  • Habit and adult size: trunk 3 to 5 m (up to 6 m) tall and 25 to 45 cm across, sometimes branched; leaves 1 to 2 m long
  • In the UK, US and Australia: Kew (BGCI) in the UK, and the hybrid with Cycas revoluta at RHS Wisley; Montgomery Botanical Center (4 accessions, 1977 to 2024), Juniper Level Botanic Garden (in the ground) and some thirty other gardens in BGCI in the US; Royal Botanic Garden Sydney (six plants), Adelaide and Townsville (BGCI) in Australia
  • Toxicity: no analysis specific to the species; treat it as poisonous, like all Cycas (see Toxicity and precautions)

How to recognise Cycas taitungensis

Cycas taitungensis looks very much like Cycas revoluta. According to Ken Hill (2008), it differs in its longer, flatter leaves, with longer, flatter leaflets whose margins are only curved down, not rolled under; its female “cones” are tighter and cabbage-shaped, and its seeds darker. De Laubenfels and Adema (1998) add longitudinal ribs on the seed shell.

Hill (2008) describes a trunk 3 m tall, sometimes 6 m, 25 to 30 cm thick and woolly at the top. The leaves, dark green and semi-glossy, are 100 to 180 cm long and carry 150 to 170 leaflets; they are moderately keeled, the two rows of leaflets forming an angle of 120 to 150°. The petiole is 15 to 20 cm long. The median leaflets measure 12 to 17 cm by 6 to 8 mm. The male cones, spindle-shaped and yellow, are 35 to 50 cm long. The megasporophylls, 21 to 26 cm long, carry 2 to 6 downy ovules and a rounded blade cut into 28 to 36 narrow lobes. The red seeds measure 40 to 45 mm by 25 to 30 mm. The Flora of China (1999) gives a trunk up to 5 m by 45 cm, sometimes branched, and leaves 1.1 to 2 m long.

These differences are not always clear-cut. Measuring 21 characters on plants of both species, Chang and colleagues (2022) found in Cycas taitungensis leaflets that are on average wider, longer and more widely spaced, shorter megasporophylls and larger seeds, but with overlapping values; seed colour and the ribs of the shell did not separate the two species.

Cycas taitungensis
Male plant of Cycas taitungensis
Cycas taitungensis
Female plant of Cycas taitungensis

Hybrids

Cycas taitungensis hybridises readily with Cycas revoluta. In eastern Taiwan, where the two species are planted side by side, Chiang and colleagues (2013) detected stronger genetic mixing in cultivated plants than in wild populations, with exchanges in both directions. In cultivation, the hybrid Cycas revoluta × Cycas taitungensis is recorded at RHS Garden Wisley, in the UK (BGCI PlantSearch), and a French grower recommends it, like Cycas taitungensis itself, because it can make two flushes of leaves in a season, while having the same frost sensitivity of the foliage (Fous de palmiers forum, 2020).

In the United States, the Juniper Level Botanic Garden (North Carolina) lists among the cycads that survived without protection in winter 2013–2014 the hybrids Cycas taitungensis × Cycas guizhouensis, Cycas taitungensis × Cycas panzhihuaensis and Cycas panzhihuaensis × (Cycas revoluta × Cycas taitungensis). BGCI also lists a Cycas taitungensis × Cycas szechuanensis at Mercer Arboretum and Botanic Gardens, in Texas.

Possible confusion

The former “Cycas taiwaniana”

Before it was described in 1994, the species was known under the name Cycas taiwaniana, wrongly applied (Hill 2008). That name in fact belongs to a cycad of south-eastern mainland China, with hairless ovules and yellow seeds, in another section. According to de Laubenfels and Adema (1998), Schuster (1932) even made taiwaniana a variety of Cycas revoluta on the basis of cultivated plants that were in fact Cycas taitungensis. Plants sold under the name Cycas taiwaniana may therefore belong to either species.

How to tell it from its relatives

  • Cycas revoluta, from southern Japan: shorter leaves (50 to 150 cm), narrower leaflets with margins clearly rolled under, a short petiole (Hill 2008). At the Jardin zoologique tropical, Cycas taitungensis stands out by its longer leaves and a slightly more massive habit.
  • Cycas taiwaniana: broad (9 to 16 mm), flat leaflets, hairless ovules and yellow seeds (Hill 2008).
  • Cycas panzhihuaensis, from Sichuan: bluish, flat leaves that are not keeled, hairless ovules and orange seeds (Hill 2008).

Taxonomy

Cycas taitungensis was described in 1994 by C. F. Shen, K. D. Hill, C. H. Tsou and C. J. Chen in the Botanical Bulletin of Academia Sinica 35. The type was collected on 28 June 1993 by C. H. Tsou (no. 825) in the Yenping cycad reserve, Taitung County, at about 500 m; the holotype is kept in the herbarium of Academia Sinica (HAST) (The World List of Cycads; Hill 2008). The original description could not be consulted.

With Cycas revoluta, the species forms the small section Asiorientales, defined by downy ovules, firm, waxy male cones and red seeds (Hill 2008). Its rank now divides the references:

  • accepting it as a species: Hill (2008), de Laubenfels and Adema (1998), the Flora of China (1999), Species+ and The World List of Cycads (version 2026.08.15), which this site follows;
  • placing it within Cycas revoluta: Chang and colleagues (2022), in a study combining morphological measurements and genomic sequencing (RAD-seq) of 26 populations of Cycas revoluta and the two populations of Cycas taitungensis, followed by Kew’s World Checklist of Vascular Plants, on which POWO is based (status checked through GBIF on 21 October 2026).

Genetic studies agree on a recent split. Chang, Huang and Liao (2019) conclude that Cycas taitungensis arose from ancestral populations of Cycas revoluta that colonised south-eastern Taiwan from the Middle Pleistocene onwards, following the Ryukyu island arc. Chang and colleagues (2022) then show that the two lineages have continued to exchange genes, through pollen and through bulbils carried by the Kuroshio current, and that their characters overlap: they conclude that there is a single species. They themselves point out the drawback of this choice for conservation, since the far more threatened Taiwanese plants would no longer be assessed separately.

This site keeps Cycas taitungensis as a separate species, in line with The World List of Cycads and with horticultural usage: this is an editorial choice, POWO remaining the botanical reference. The Cycas revoluta page on this site sets out the same divergence.

Etymology and history

The epithet comes from Taitung County, a mountainous region in the south-east of Taiwan, with the Latin ending -ensis, “originating from” (Hill 2008; Haynes 2022, as taken up by The World List of Cycads).

The Taiwanese plants were described and illustrated as early as the 1920s under the name Cycas taiwaniana, notably by Yamamoto (1928), and later in the floras of Taiwan (de Laubenfels and Adema 1998). Chang and colleagues (2022) consider that this confusion distorted comparisons with Cycas revoluta, the original description included. A reserve was created specifically for the species in Taitung County (Hill 2008). In France, it has been grown by amateurs since at least the 2000s (Fous de palmiers forum).

Common names

In English, Hill (2008), after Chen and colleagues (1995) and Bonta and Osborne (2007), records the horticultural name “emperor sago”, which the University of Florida extension service also uses (“Emperor Sago Palm”). The PACSOA wiki of the Palm and Cycad Societies of Australia adds “prince sago”. The North Carolina nursery Plant Delights sells it as “Tongue Tied Sago Palm”, a trade name. In Chinese, the Flora of China gives tai-dong su-tie (台东苏铁, “Taitung cycad”), and Hill (2008) also cites feng-wei-jiao, “phoenix-tail palm”; Species+ gives Taiwan-feng-wei-jiao.

In the wild

Cycas taitungensis is endemic to Taitung County, in south-eastern Taiwan. Only two populations remain, on either side of the East Rift Valley: one in the cycad nature reserve of Hongye village, along the Luye valley, the other in the cycad forest reserve of the Coastal Range (Chang and colleagues 2022; Huang and colleagues 2001). The plants grow on steep, exposed slopes, sometimes in open forest, between about 300 and 900 m (Chang and colleagues 2022); the Flora of China gives (300–)400 to 800(–1,000) m, on rocky slopes or well-drained gravels. De Laubenfels and Adema (1998) also mentioned northern Fujian, in China, which neither Hill (2008) nor The World List of Cycads retains.

According to the Flora of China, pollination takes place from April to June and the seeds ripen in September and October. Huang and colleagues (2001) found high genetic diversity and little difference between the two populations.

Conservation status and regulation

The IUCN lists Cycas taitungensis as Endangered (EN A3e; B1ab(v)), in the assessment by J. D. Bösenberg published in 2022: criterion A3e refers to an expected decline caused by introduced organisms, and B1ab(v) to a small, fragmented range with a continuing decline in the number of mature plants (category checked with GBIF and The World List of Cycads). The previous assessment, by J. Haynes (2010), had already moved it from Vulnerable to Endangered (Chang and colleagues 2022).

The threats cited are habitat disturbance, poaching, the closing-in of lowland forests and, above all, two pests, the cycad scale, Aulacaspis yasumatsui, and the cycad blue butterfly, Chilades pandava, which are more serious for this species than for Cycas revoluta (Chang and colleagues 2022). Hill (2008) already noted that the reserve created for the species is small and subject to landslides and erosion.

Like the whole family Cycadaceae, the species has been listed in CITES Appendix II since 4 February 1977, with annotation #4 (CoP20 version, in force since 5 March 2026): seeds, pollen and seedlings in sterile containers are not covered by CITES. In the European Union, it falls under Annex B of Regulation (EC) No 338/97 (annexes set by Regulation (EU) 2026/1383, applicable since 29 June 2026). Databases consulted on 19 October 2026: check the regulations in force before any purchase and prefer seed-grown plants raised in cultivation.

Growing Cycas taitungensis

Cycas taitungensis is grown like Cycas revoluta, whose needs it shares: sun, well-drained soil, watering in summer and drier soil in winter. Growers who know both agree that it is more vigorous, with longer leaves and an earlier start in spring.

Outdoor and in-ground cultivation

At the Jardin zoologique tropical at La Londe-les-Maures, on the Var coast in the south of France, several plants grow in the ground: one was planted young, with a caudex about ten centimetres across, two others with an already developed trunk. Their growth has always been fairly rapid, and the article published on the French side of this site judges them probably among the easiest cycads for the south-east of France, worth trying wherever Cycas revoluta succeeds. This Mediterranean experience is relevant to gardeners in comparable climates, such as coastal California or southern Australia, although no equivalent trial from those regions has been published.

French growers confirm its vigour. In Roussillon, a grower notes on the Fous de palmiers forum (2009 and 2011) that it starts earlier and grows faster than Cycas revoluta, with longer, flatter leaves; in the Béarn, another sees growth start earlier than in Cycas revoluta every spring (2009 and 2012). The same Béarn grower found that the leaves of a late flush, in September, did not have time to harden and were scorched the following winter, whereas those of the spring flush held: it is better not to push growth in late summer, a precaution drawn from this single report.

In the United States, Plant Delights Nursery (North Carolina), which visited the wild populations in 2008, reports that its plants form in seven to nine years “a large rosette of stunning 5’ long” leaves (about 1.5 m) around a trunk that can eventually reach 10 feet (about 3 m), and advises planting early in the season and mulching well until the trunk is robust. The PACSOA wiki recommends a moist, well-drained spot in full sun with regular feeding, and calls it “said to be the fastest grower of all the cycads”, a claim it does not source.

Container cultivation

No growing report specific to pot culture is documented. The University of Florida extension service notes that it makes a good container specimen for the patio, like Cycas revoluta. Given the size of adult leaves, a large container and a sunny position are needed.

In cultivation in the UK, US and Australia

  • United Kingdom: Kew lists the species in BGCI PlantSearch, and RHS Garden Wisley the hybrid Cycas revoluta × Cycas taitungensis. These listings show a declaration, not necessarily a living plant today, and no British outdoor trial has been published.
  • United States: the online catalogue of Montgomery Botanical Center (Coral Gables, Florida) lists four accessions, whose numbers date them to 1977, 1998, 1999 and 2024; Fairchild Tropical Botanic Garden also lists it in its own catalogue. The Juniper Level Botanic Garden, near Raleigh (North Carolina), grows it in the ground without protection (see Cold hardiness). BGCI PlantSearch adds some thirty gardens, from The Huntington, Ganna Walska Lotusland, San Diego Botanic Garden, the San Diego Zoo and the University of California Botanical Garden at Berkeley to the Atlanta Botanical Garden, Sarah P. Duke Gardens (North Carolina), the Arnold Arboretum and the New York Botanical Garden; in the colder of these gardens the plants are presumably under glass, which the lists do not say.
  • Australia: the online catalogue of the Royal Botanic Garden Sydney (updated on 1 October 2026) lists six plants of garden origin, from accessions of 1997, 2002, 2021 and 2022, most of them in beds 89a and 89b; BGCI adds the Botanic Garden of Adelaide, James Cook University in Townsville and the System Garden of the University of Melbourne.

Propagation

Cycas taitungensis is propagated from seed; a male and a female plant are needed to obtain seed, which ripens in autumn. French amateurs report rapid growth of seedlings (Fous de palmiers forum, 2009). As in Cycas revoluta, the plant can form bulbils: Chang and colleagues (2022) attribute to them a role in natural dispersal by sea. No protocol specific to the species is published.

Pests and diseases

In the wild, the cycad scale, Aulacaspis yasumatsui, and the cycad blue butterfly, Chilades pandava, weaken the Taiwanese populations (Chang and colleagues 2022); a 2010 paper describes the life cycle of this scale reared on cycads in Taiwan. In cultivation the risks are those of the genus: scale insects and rot in waterlogged soil. At the Jardin zoologique tropical, an abnormal leaf was photographed on one plant, with no cause given.

Cold hardiness

Cycas taitungensis copes well with frosts on the Mediterranean coast, down to −6 °C (21 °F) without damage at the Jardin zoologique tropical in February 2012. Several growers nevertheless find its foliage more sensitive than that of Cycas revoluta, while the plant itself recovers from harder frosts.

European experience

  • South of France, Var coast: at the Jardin zoologique tropical at La Londe-les-Maures, plants in the ground came through −6 °C (21 °F) without damage in February 2012, with a thaw during the day (article and earlier page on the French side of the site).
  • Roussillon (Pyrénées-Orientales, France): a grower reports on the Fous de palmiers forum (March 2010) that his plant, in the ground, stayed intact after a winter with 27 nights of frost, a minimum of −6 to −7 °C (21.2 to 19.4 °F) and 40 cm of snow, whereas the snow had slightly scorched some Cycas revoluta; in February 2012 he adds that it took −7 °C twice without damage, “but that is the limit”.
  • Béarn (south-west France): a grower reports on the same forum that the foliage of his plant in the ground was badly damaged at −5 to −6 °C (23 to 21.2 °F) in January 2009, while his Cycas revoluta was untouched; he sees damage from −6 °C (21.2 °F) (April 2010) and complete defoliation at −10 °C (14 °F) in February 2012, without fearing for the plant’s survival.
  • Paris region: a grower in the suburbs of Paris reports (April 2010) that his plant, in the ground for more than two years, was defoliated by −12 °C (10.4 °F) in winter 2008–2009; the caudex, 8 to 10 cm across, stayed sound, but the plant took two years to make new leaves (February 2012).

Together, these reports suggest foliage damaged at around −5 to −7 °C depending on humidity and the length of the frost, and survival of the trunk in harder frosts: a synthesis of isolated reports, not a measurement. The Mediterranean results of the Var and Roussillon are the most useful for gardeners in similar climates.

United Kingdom, United States and Australia

  • United States, North Carolina: the Juniper Level Botanic Garden, near Raleigh, reports that after winter 2013–2014, with minima of 4 to 9 °F (about −16 to −13 °C) depending on the spot, its Cycas taitungensis in the ground, without protection or mulch, survived while losing almost all their leaves, whereas Cycas revoluta appears in its list of cycads that did not survive. The garden adds that Cycas revoluta holds its foliage to a lower temperature, but that Cycas taitungensis is ultimately the hardier plant; in 2022 it reported that all its Cycas lost their leaves at 16 °F (about −9 °C) and then regrew, still without protection. Its associated nursery, Plant Delights, states that the foliage burns back at 20 °F (about −7 °C) and that all its plants resprouted after 7 °F (about −14 °C) in 2009.
  • United States, ratings: the University of Florida extension service (Baker County, 2013) gives Cycas revoluta and Cycas taitungensis together USDA zones 8 to 11, a hardiness of 10 °F (about −12 °C) and leaves that burn in the 20s °F (about −7 to −1 °C). Plant Delights rates it for zones 7b to 10b, a commercial rating based on its own garden.
  • Australia: the PACSOA wiki describes it as frost tolerant, able to withstand −10 °C (14 °F).
  • United Kingdom: no outdoor result has been published. Given the reports above, it would only be worth a trial in the mildest, driest sites, with the foliage likely to suffer in a hard winter; this is a deduction, not a result.

Toxicity and precautions

No toxicity analysis specific to Cycas taitungensis has been published, but every Cycas species studied contains cycasin, which digestion converts into methylazoxymethanol, toxic to the liver and nervous system, along with a neurotoxic amino acid, BMAA, above all in the seeds. The ASPCA lists Cycas revoluta, its closest relative, among plants toxic to dogs, cats and horses, and the University of Florida notes that all parts of both species, especially the seeds, are very toxic. Treat the plant as poisonous: keep seeds out of reach of children and pets, wear gloves to handle them and, if any part is swallowed, contact a poison centre, a doctor or a vet straight away.

Traditional uses

No traditional use specific to Cycas taitungensis is documented. Chiang and colleagues (2013) only report that the species and Cycas revoluta are planted as ornamentals in eastern Taiwan. The PACSOA wiki states that it “is used to make tea in its local area”, without a source; no other published source confirms this, and given the toxicity of the genus it is in no way a recommendation.

Frequently asked questions

Is Cycas taitungensis a true species?

It depends on the reference. The World List of Cycads, the Flora of China and Hill (2008) accept it; POWO has placed it within Cycas revoluta since the study by Chang and colleagues (2022). This site treats it as a separate species.

How can I tell it from Cycas revoluta?

By its longer (100 to 180 cm) and flatter leaves, its longer leaflets with margins only curved down and its more massive habit. The differences overlap in some plants, however.

Is it hardier than Cycas revoluta?

Not in its foliage, which is often damaged sooner. The trunk, on the other hand, seems at least as tough: at the Juniper Level Botanic Garden it survived about −16 to −13 °C (4 to 9 °F) without protection, whereas Cycas revoluta did not survive the garden’s winters.

Does it grow faster than Cycas revoluta?

Yes, according to French growers and the experience of the Jardin zoologique tropical: it grows faster and starts into growth earlier in spring.

Can it be grown outdoors in the UK?

Possibly, in the mildest areas, but no British trial has been published. In France and North Carolina it has survived frosts of −10 °C (14 °F) and below in the ground, losing its leaves: try it only in a sheltered, free-draining spot.

Is it endangered?

Yes, it is listed as Endangered (2022): only two populations remain in Taiwan, weakened in particular by the cycad scale.

Is it poisonous?

It should be assumed so. No specific analysis exists, but every cycad studied contains serious toxins, especially in the seeds.

Further reading on Succulentes

Sources

Reference sites

Bibliography

  • Shen, C.F., Hill, K.D., Tsou, C.H. & Chen, C.J. (1994). Cycas taitungensis C.F. Shen, K.D. Hill, C.H. Tsou & C.J. Chen, sp. nov. (Cycadaceae), a new name for the widely known cycad species endemic in Taiwan. Botanical Bulletin of Academia Sinica 35: 133–140 (description pp. 135–138). [Original description; reference after The World List of Cycads, Hill 2008 and Chang and colleagues 2022.]
  • Laubenfels, D.J. de & Adema, F. (1998). A taxonomic revision of the genera Cycas and Epicycas gen. nov. (Cycadaceae). Blumea 43(2): 351–400. [Description, ribs of the seed, confusion with Cycas taiwaniana, mention of Fujian.]
  • Chen, C.J. & Stevenson, D.W. (1999). Cycadaceae. In Wu, Z.Y. & Raven, P.H. (eds), Flora of China 4. Science Press, Beijing; Missouri Botanical Garden Press, St Louis. [Description, altitude, phenology; online version.]
  • Huang, S., Chiang, Y.C., Schaal, B.A., Chou, C.H. & Chiang, T.Y. (2001). Organelle DNA phylogeography of Cycas taitungensis, a relict species in Taiwan. Molecular Ecology 10(11): 2669–2681. doi:10.1046/j.0962-1083.2001.01395.x [Two populations, genetic diversity.]
  • Hill, K.D. (2008). The genus Cycas (Cycadaceae) in China. Telopea 12(1): 71–118. doi:10.7751/telopea20085804 [Description, type, vernacular names, distinction from Cycas revoluta, reserve, status.]
  • Bailey, R., Chang, N.T., Lai, P.Y. & Hsu, T.C. (2010). Life table of cycad scale, Aulacaspis yasumatsui (Hemiptera: Diaspididae), reared on Cycas in Taiwan. Journal of Asia-Pacific Entomology 13(3): 183–187. doi:10.1016/j.aspen.2010.03.008 [Scale reared on cycads in Taiwan; title and reference checked on Crossref.]
  • Chiang, Y.C., Huang, B.H., Chang, C.W., Wan, Y.T., Lai, S.J., Huang, S. & Liao, P.C. (2013). Asymmetric introgression in the horticultural living fossil Cycas sect. Asiorientales using a genome-wide scanning approach. International Journal of Molecular Sciences 14(4): 8228–8251. doi:10.3390/ijms14048228 [Introgression between cultivated plants in Taiwan.]
  • Chang, J.T., Huang, B.H. & Liao, P.C. (2019). Genetic evidence of the southward founder speciation of Cycas taitungensis from ancestral Cycas revoluta along the Ryukyu Archipelagos. Conservation Genetics 20: 1045–1056. doi:10.1007/s10592-019-01193-1 [Origin from Cycas revoluta in the Middle Pleistocene.]
  • Chang, J.T., Chao, C.T., Nakamura, K., Liu, H.L., Luo, M.X. & Liao, P.C. (2022). Divergence with gene flow and contrasting population size blur the species boundary in Cycas sect. Asiorientales, as inferred from morphology and RAD-seq data. Frontiers in Plant Science 13: 824158. doi:10.3389/fpls.2022.824158 [Cycas taitungensis reduced to a synonym of Cycas revoluta, morphometrics, populations, threats.]
  • Haynes, J. (2010). Cycas taitungensis. The IUCN Red List of Threatened Species 2010: e.T42067A10642224. doi:10.2305/IUCN.UK.2010-3.RLTS.T42067A10642224.en [Previous assessment; reference checked on Crossref.]
  • Bösenberg, J.D. (2022). Cycas taitungensis. The IUCN Red List of Threatened Species 2022: e.T42067A69826816. doi:10.2305/IUCN.UK.2022-1.RLTS.T42067A69826816.en [Current assessment (EN); reference checked on Crossref.]
  • Haynes, J.L. (2022). Etymological compendium of cycad names. Phytotaxa 550(1): 1–31. doi:10.11646/phytotaxa.550.1.1 [Etymology; used through The World List of Cycads.]
  • Calonje, M., Stevenson, D.W. & Osborne, R. (2026). The World List of Cycads, version 2026.08.15. Montgomery Botanical Center, Coral Gables. doi:10.5281/zenodo.21958524 [Reference checklist.]