Cycas sexseminifera

Cycas sexseminifera is a small cycad of the limestone karst of Guangxi, in southern China, and of northern Vietnam, where it grows in cracks in limestone rock, often on vertical cliffs with no visible soil. This species of the genus Cycas was described in 1996 by the Chinese botanist Wei Fa-Nan, from a plant grown at Guilin Botanical Garden. The Flora of China treats it under the name Cycas miquelii, a name misapplied to it according to Hill (2008) but still found in books, on labels and in nursery lists. Several species later described from the limestone hills of Guangxi are now included in it. The IUCN lists it as Least Concern.

Key facts about Cycas sexseminifera

  • Accepted name: Cycas sexseminifera F.N.Wei (1996), accepted by The World List of Cycads (version 2026.08.15) and by GBIF; POWO could not be consulted
  • Former names and synonyms: Cycas longisporophylla F.N.Wei, Cycas spiniformis J.Y.Liang, Cycas brevipinnata Hung T.Chang, Y.Y.Huang & Y.C.Zhong and Cycas septemsperma Hung T.Chang, Y.Y.Huang & H.X.Zheng; also Cycas acuminatissima and Cycas crassipes according to Hill (2008) and Species+; called Cycas miquelii, in error, by the Flora of China
  • Family: Cycadaceae, order Cycadales; section Stangerioides (Hill 2008)
  • Common names: no English name in botanical sources; “dwarf sago” in the British nursery trade (Trebrown); in Chinese 石山苏铁 (shi shan su tie), given by the Flora of China under the name Cycas miquelii
  • Natural range: China (southern and central Guangxi), northern Vietnam (Cao Bằng, Ninh Bình and Thanh Hóa provinces)
  • IUCN status: Least Concern (LC); assessment by K.D. Hill (2010), category kept in the reassessment by J.D. Bösenberg published in Red List version 2023-1, according to GBIF
  • CITES and other protection: CITES Appendix II (seeds exempt under annotation #4); Annex B in the European Union
  • Documented hardiness: no published cold test; two nurseries rate it USDA zone 9b, a commercial classification (see Cold hardiness)
  • Light and soil: in the wild, cracks in bare limestone, in full exposure or half shade; no published cultivation trial
  • Habit and adult size: dwarf; trunk underground or up to 1 m tall, 8 to 20 cm across; leaves 50 to 120 cm long
  • In the UK, US and Australia: Glasgow Botanic Gardens, Montgomery Botanical Center (Florida), Huntington, San Diego Botanic Garden, Naples Botanical Garden, Royal Botanic Garden Sydney and Cairns, among others (see In cultivation)
  • Toxicity: no data specific to the species; treat it as poisonous, like all Cycas (see Toxicity and precautions)

How to recognise Cycas sexseminifera

It is recognised by its dwarf habit, with a short trunk and short, flat leaves, by its short, narrow, flat, rather stiff and sharp-pointed leaflets, and by the small but broad sterile blade of its megasporophylls, which ends in a broad apical spine clearly distinct from the lateral spines. These are the characters Hill (2008) considers the most useful; the petiole is often spineless, but not consistently so. The description below is Hill’s (2008).

  • Trunk: underground or upright, 0 to 1 m tall and 8 to 20 cm in diameter, with 4 to 20 leaves in the crown.
  • Leaves: deep green and semi-glossy, flat or slightly keeled, 50 to 120 cm long, with 80 to 200 leaflets and a brown down shed as the leaf expands; the rachis always ends in a pair of leaflets; petiole 10 to 40 cm, hairless, spineless or spiny along 5 to 100% of its length.
  • Leaflets: strongly two-toned, 13 to 24 cm long and 6 to 10 mm wide, with flat or slightly recurved margins and a sharp, spiny tip, set 8 to 14 mm apart.
  • Cataphylls (the scale leaves that protect the growing point): narrowly triangular, soft and hairy, 3 to 5 cm long.
  • Male cones: narrowly ovoid to spindle-shaped, yellow, 15 to 30 cm long and 5 to 8 cm across, with soft microsporophylls whose apical spine is rudimentary or absent.
  • Megasporophylls (the seed-bearing leaves of female plants): 8 to 12 cm long, brown-felted, with 2 to 6 hairless ovules; the sterile blade is round, 35 to 55 mm long and 30 to 50 mm wide, deeply comb-like, with 16 to 28 soft lateral spines 10 to 25 mm long and a distinct apical spine 30 to 40 mm long.
  • Seeds: ovoid, 20 to 28 mm long and 18 to 25 mm wide; the fleshy coat (sarcotesta) is yellow, not powdery and without a fibrous layer; the stony layer is smooth to warty.

The Flora of China, which describes the species as Cycas miquelii, gives somewhat different figures: a trunk usually underground, sometimes up to 60 cm above ground, 25 to 40 leaves 50 to 100 cm long with 60 to 100 pairs of leaflets 13 to 18 cm long and 14 to 18 mm wide, and megasporophylls 8 to 14 cm long. The leaflet width in particular differs markedly from Hill’s figures.

Hybrids

No natural or garden hybrid is documented. The difficulty of the group lies instead in the limits between species (see Taxonomy).

Possible confusion

The closest species is Cycas ferruginea, which grows in the same kind of habitat, on the same limestone cliffs of Guangxi and northern Vietnam. In Hill’s key (2008), the two are separated by the size of the sterile blade of the megasporophylls: 35 to 55 mm by 30 to 50 mm in Cycas sexseminifera, 70 to 110 mm by 50 to 80 mm in Cycas ferruginea, which is also recognised by the dense rust-coloured down on its new growth, its longer leaves and its longer, often arching leaflets. The Flora of China adds that Cycas ferruginea has light green, thin leaflets, hairy above and not sharp-pointed, whereas those of Cycas sexseminifera (its Cycas miquelii) are dark green, leathery, hairless and sharp-pointed. Cycas tropophylla also grows on bare limestone faces (Hill 2008); it differs in its distinctly keeled leaves, a character unique among the cycads of northern Vietnam according to the etymology given by The World List of Cycads (Haynes 2022).

The name Cycas inermis, which belongs to a species of southern Vietnam, was applied to it by Metcalf in 1942, precisely because its petioles are often spineless; later Chinese works confused it with Cycas pectinata, which grows in China but much farther west (Hill 2008). The Flora of China also notes that Chinese plants of this species have been misidentified as Cycas siamensis.

Taxonomy

Cycas sexseminifera is a name accepted by The World List of Cycads and by GBIF; POWO could not be consulted. Wei Fa-Nan described it in 1996 in the journal Guihaia (16(1): 1), from a plant grown at Guilin Botanical Garden that had been introduced from Longzhou county, in Guangxi (F.N. Wei 2223, 1994; holotype at the herbarium of the Guangxi Institute of Botany, IBK). That original description could not be read: its details come from The World List of Cycads and Hill (2008).

The species belongs to section Stangerioides, a Sino-Vietnamese group with soft male cones, hairless ovules and yellow seeds with a more or less warty stony layer (Hill 2008). In the late 1990s several very similar species were described from the karst of Guangxi, four of them from cultivated plants: Cycas longisporophylla and Cycas spiniformis (1997, from plants at Guilin Botanical Garden introduced from Longzhou), Cycas brevipinnata and Cycas septemsperma (1998, from plants at the Nanning arboretum), then Cycas acuminatissima (1998) and Cycas crassipes (1999). Hill (2008) united them all under Cycas sexseminifera. The World List of Cycads keeps the first four as synonyms but places Cycas acuminatissima and Cycas crassipes under Cycas segmentifida, as the Flora of China (Chen and Stevenson 1999) had already done for the first of them; Species+, on the other hand, lists all six names as synonyms of Cycas sexseminifera. The disagreement remains open.

The name Cycas miquelii

Wang (1996) and then the Flora of China (Chen and Stevenson 1999) used the name Cycas miquelii Warb. for these plants, and the Flora of China lists Cycas sexseminifera and four of its synonyms under it. Hill (2008) showed that this was a misapplication. Warburg, who described Cycas miquelii in 1900, cited no type and gave only “Süd-China” as its origin; the original material, sheets at Utrecht from a plant grown in the Amsterdam botanic garden, shows somewhat aberrant forms of Cycas revoluta without petiole spines, so Cycas miquelii is a synonym of Cycas revoluta. Hill also rejected the neotype chosen in 1998 by de Laubenfels and Adema, whose own concept of Cycas miquelii mixed this species with others: their neotype is a specimen from southern Thailand that belongs to Cycas clivicola.

For the reader, the label “Cycas miquelii” is therefore ambiguous. In Chinese literature and in the Flora of China it means this species; in nomenclature it is a synonym of Cycas revoluta; and plants or texts that follow the 1998 revision may refer to Cycas clivicola. The confusion persists in horticultural databases: the plant profile of the Royal Horticultural Society files both Cycas miquelii and Cycas sexseminifera as synonyms on its page for the Japanese sago palm, Cycas revoluta, and a search for “Cycas miquelii” in the online catalogue of Montgomery Botanical Center returns both its Cycas revoluta and its Cycas sexseminifera accessions (both consulted on 24 October 2026). When buying a plant under either name, ask for the origin and check the characters given above.

A recent genomic study

Xi, Liu, Gong and Feng (2025), using genome-wide data (ddRAD-seq) and morphology, studied the “Cycas sexseminifera complex”, six similar taxa described from the karst mountains of south-western China. Their sampling covered four of them: Cycas ferruginea, Cycas longisporophylla, Cycas sexseminifera and Cycas spiniformis; Cycas brevipinnata and Cycas septemsperma could not be included, as no wild population or cultivated plant was available. The analyses separated two groups, and the authors recognise two species: Cycas ferruginea and a redefined Cycas sexseminifera that includes Cycas longisporophylla and Cycas spiniformis. Only the abstract of this article could be read.

Etymology and history

The epithet comes from the Latin sex, “six”, and seminifera, “seed-bearing”: it refers to the six seeds observed on a megasporophyll of the type plant (Haynes 2022). Hill (2008) notes that the author wrongly believed this number to be a distinguishing character; the species actually carries 2 to 6 ovules per megasporophyll.

The species was long confused with others: Metcalf (1942) called it Cycas inermis, later Chinese works (Cheng et al. 1975; Zhou et al. 1990) confused it with Cycas pectinata, and several authors overlooked its presence in Vietnam (Hill 2008). Its type, like those of several of its synonyms, was described from plants grown in gardens and nurseries in Guangxi, and specimens cited by Hill (2008) include plants grown in a Nanning park and in a village garden in Vietnam: the species was clearly already in local cultivation. No date of introduction into Western collections is documented; the oldest dated accessions found are those of Montgomery Botanical Center, from 1993 (see In cultivation).

Common names

No English common name is attested in botanical sources. The British nursery Trebrown sells it as “dwarf sago”, a trade name that echoes its small size and the “sago palm” name of Cycas revoluta. The Flora of China, which treats it as Cycas miquelii, gives the Chinese name 石山苏铁 (shi shan su tie). No Vietnamese name was found in the sources consulted.

In the wild

Cycas sexseminifera is widespread in southern and central Guangxi, in China, and in a limited area of Cao Bằng province, in northern Vietnam, on the border with Guangxi, with a disjunct occurrence in Thanh Hóa province, south of Hanoi (Hill 2008); The World List of Cycads also cites Ninh Bình province, where Hill collected a plant grown in a village garden, taken from the hill behind the village. Locally abundant, it grows in crevices in bare outcrops in rugged karst country, often on vertical faces with no visible soil (Hill 2008). Zheng and colleagues (2017) describe it on steep cliffs and in exposed rock crevices. The Flora of China, by contrast, gives half-shaded rock crevices in broad-leaved forest on limestone mountains, often on north-facing slopes, between 200 and 500 m, with pollination in March and April and seeds ripe from August to October. The French specialist nursery Cycadales describes it growing in pockets of organic matter on limestone cliffs.

Conservation status and regulation

The IUCN lists Cycas sexseminifera as Least Concern (LC), following the assessment by K.D. Hill (2010); a reassessment by J.D. Bösenberg, dated 2020, was published in version 2023-1 of the Red List (reference found on Crossref), and the Red List data relayed by GBIF give the same category (consulted on 24 October 2026). Donaldson (2003) had previously listed it as Near Threatened (NT). Hill (2008) reports a clear demand on horticultural markets in China and Vietnam and substantial collection from the wild for this trade, but notes that the species is extremely abundant at many inaccessible sites. In China it occurs in several protected areas in Guangxi, including the Daming Mountains, Nonggang and Chongzuo national nature reserves (Zheng et al. 2017).

Like every species in the genus except Cycas beddomei, Cycas sexseminifera falls under CITES Appendix II, where the family Cycadaceae has been included since 4 February 1977. Annotation #4 (CoP20 version, in force since 5 March 2026) exempts seeds, pollen, seedlings and tissue cultures obtained in vitro and transported in sterile containers, and cut flowers of artificially propagated plants; international trade in the plants themselves requires an export permit. The United Kingdom, the United States and Australia apply CITES through their own legislation; in the European Union the species is in Annex B of Regulation (EC) No 338/97, as set by Commission Regulation (EU) 2026/1383, applicable since 29 June 2026. Species+, the official CITES database, lists the species under its own name and confirms this status. This information was checked in October 2026 and does not replace the official texts: check the rules in force, ask for proof of origin and prefer plants raised from seed in cultivation, all the more so as the species is collected from the wild for the trade.

Growing Cycas sexseminifera

In short: it is grown in several botanic gardens and offered by specialist nurseries, but no institution has published a cultivation trial; what follows comes from nursery descriptions and from its habitat.

The French specialist nursery Cycadales describes it as one of the smallest Cycas, with the smallest seeds in the genus, very slow-growing (it estimates a plant with a 13 cm caudex at 20 years old or more), and suited to bonsai-style growing in a small container; it gives full sun or half shade as suitable exposures (product pages consulted on 24 October 2026). These are a nursery’s statements, not trial results.

Outdoor and in-ground cultivation

No result in the open ground has been published outside its native range. Its habitat suggests a very free-draining, stony, probably limy soil and no standing water; this is a deduction from the wild, not a documented result. Outdoors it can only be considered in frost-free or nearly frost-free climates, and no garden in a climate with regular frost has reported on it.

Container cultivation

Its small size suits pot culture, according to the nursery quoted above, and it is sold in Europe as a container plant; in the United Kingdom, a pot in a frost-free glasshouse or conservatory is the safe option. No grower’s report with dates and temperatures was found in English.

In cultivation in the UK, US and Australia

In short: it is present in a good number of botanic gardens in all three countries, mostly declared to BGCI, with twelve accessions at Montgomery Botanical Center.

  • United Kingdom: Glasgow Botanic Gardens declares it to BGCI. The British nursery Trebrown lists it (commercial zone 9b rating).
  • United States: Montgomery Botanical Center, in Coral Gables (Florida), lists twelve accessions in its online catalogue, numbered 9512, 9950, 93227, 93228 and 951552 to 951562; the numbers date two of them to 1993 and eight to 1995, while the two four-digit numbers give no year (consulted on 24 October 2026). The Huntington (San Marino, California), San Diego Botanic Garden (Encinitas), Naples Botanical Garden (Florida), Atlanta Botanical Garden, Moore Farms Botanical Garden (South Carolina) and the University of Minnesota conservatory also declare it to BGCI.
  • Australia: the Royal Botanic Garden Sydney lists it in its online catalogue (inventory of 19 October 2026) and declares it to BGCI; the Cairns Botanic Gardens also declare it.

A BGCI declaration shows that a garden held the plant at some point, not that it is alive today, and none of these sources says whether it grows outdoors or under glass. Elsewhere, BGCI lists gardens in China, the Czech Republic, Spain and France. No report from a private grower was found.

Propagation

The plant is dioecious: seed requires a male and a female plant. In the wild, pollination takes place in March and April and seeds ripen from August to October (Flora of China). No germination data specific to the species have been published. Seeds are exempt from CITES under annotation #4. The RHS profile mentions propagation by seed or suckers, but as that profile concerns Cycas revoluta (see Taxonomy), it says nothing reliable about this species.

Pests and diseases

No pest or disease specific to the species is documented in the sources consulted. In cultivation, as with any Cycas, scales such as Aulacaspis yasumatsui can attack it, and overwatering or poor drainage rots the trunk and roots.

Cold hardiness

No published, verifiable cold-tolerance data exist for Cycas sexseminifera. It lives under a subtropical monsoon climate. Two nurseries give it a USDA zone 9b rating, that is an average annual minimum of −3.9 to −1.1 °C (25 to 30 °F): Trebrown in Britain, and Cycadales in France, which adds that cold hardiness varies with the place and with the size and origin of the plant. These are commercial classifications, not the results of documented trials.

Mediterranean and European experience

No dated cultivation result in the open ground has been published in Europe, and no dated frost episode concerns this species. The Jardin zoologique tropical at La Londe-les-Maures, in the Var, has published no observation on it.

United Kingdom, United States and Australia

No cold reading was found in any of the three countries. The RHS hardiness rating H3 (−5 to 1 °C, 23 to 34 °F) shown on its page for this name belongs to its profile of Cycas revoluta, under which the name is filed as a synonym, and must not be read as a rating for Cycas sexseminifera. In the absence of data, treat it as frost-tender: a frost-free glasshouse in the UK, and in mild climates a sheltered spot where frost is rare and brief.

Toxicity and precautions

No toxicity study specific to Cycas sexseminifera has been found, but the risk is well documented in the genus: Cycas tissues, and the seeds above all, contain cycasin, which is converted during digestion into methylazoxymethanol, toxic to the liver and nervous system, along with a neurotoxic amino acid, BMAA. The ASPCA lists the sago palm (Cycas revoluta) as poisonous to dogs, cats and horses. Treat this species as poisonous: keep seeds and leaves out of reach of children and animals and wear gloves to clean seeds. If any part is swallowed, contact a poison centre, a doctor or a vet straight away.

Traditional uses

No traditional use specific to the species is documented. Its known use is ornamental: Hill (2008) reports the demand on horticultural markets in China and Vietnam.

Frequently asked questions

What does sexseminifera mean?

“Bearing six seeds”, in Latin: the author had counted six seeds on a megasporophyll of the type plant and wrongly believed this number was characteristic.

Are Cycas miquelii and Cycas sexseminifera the same plant?

Often, in practice. The Flora of China describes this species as Cycas miquelii, but according to Hill (2008) that name belongs to forms of Cycas revoluta, and a 1998 neotype tied it to Cycas clivicola; the correct name for the plants of the Guangxi karst is Cycas sexseminifera.

Where does it grow in the wild?

In cracks in limestone rock in southern and central Guangxi, China, and in northern Vietnam, often on vertical cliffs.

How do I tell it from Cycas ferruginea?

By the sterile blade of the megasporophylls, much smaller (35 to 55 mm against 70 to 110 mm), and by its dark green, leathery, sharp-pointed leaflets, whereas Cycas ferruginea has rusty-felted new growth and longer, thinner leaflets.

Is it a good cycad for a small pot?

According to a specialist nursery, yes: it is one of the smallest Cycas and suits bonsai-style container growing, but it grows very slowly.

Is it endangered?

Not much. The IUCN lists it as Least Concern because it remains very abundant on inaccessible sites, although it is collected from the wild for the horticultural trade.

Is it hardy in the UK?

Not proven. No cold data exist; nurseries rate it zone 9b, and the RHS H3 rating shown for the name actually concerns Cycas revoluta. Grow it in a frost-free glasshouse.

Is it poisonous?

It should be assumed so. No analysis exists for this species, but all the Cycas studied contain serious toxins, above all in the seeds.

Further reading on Succulentes

Sources

Reference sites

Bibliography

  • Wei, F.N. (1996). [Cycas sexseminifera]. Guihaia 16(1): 1. [Original description; not consulted, cited from The World List of Cycads and Hill (2008).]
  • Hill, K.D. (2008). The genus Cycas (Cycadaceae) in China. Telopea 12(1): 71–118. doi:10.7751/telopea20085804 [Description, synonymy and types (pp. 108–110), history of the names, lectotype of Cycas miquelii and rejection of the 1998 neotype, key, range, habitat, status, trade; full text consulted.]
  • Hill, K.D., Nguyễn, T.H. & Lộc, P.K. (2004). The genus Cycas (Cycadaceae) in Vietnam. The Botanical Review 70(2): 134–193. [Vietnamese populations (pp. 166–168); not consulted, reference found on The World List of Cycads.]
  • Chen, C.J. & Stevenson, D.W. (1999). Cycadaceae. In: Wu, Z.Y. & Raven, P.H. (eds), Flora of China, vol. 4: 1–7. Science Press, Beijing; Missouri Botanical Garden Press, St Louis. [Treatment under the name Cycas miquelii; text consulted on eFloras.]
  • de Laubenfels, D.J. & Adema, F. (1998). A taxonomic revision of the genera Cycas and Epicycas gen. nov. (Cycadaceae). Blumea 43: 351–400. [Concept and neotype of Epicycas miquelii; cited from Hill (2008).]
  • Xi, H.-H., Liu, J., Gong, X. & Feng, X.-Y. (2025). Integrative species delimitation of the Cycas sexseminifera complex (Cycadaceae) utilizing genomic and morphological data. Taxon 75(1): e70029. doi:10.1002/tax.70029 [Delimitation of the complex by ddRAD-seq and morphology; peer-reviewed article, abstract only read (Crossref).]
  • Zheng, Y., Liu, J., Feng, X. & Gong, X. (2017). The distribution, diversity, and conservation status of Cycas in China. Ecology and Evolution 7(9): 3212–3224. doi:10.1002/ece3.2910 [Habitat and protected areas in Guangxi; full text consulted.]
  • Hill, K.D. (2010). Cycas sexseminifera. The IUCN Red List of Threatened Species: e.T42084A10624720. doi:10.2305/IUCN.UK.2010-3.RLTS.T42084A10624720.en [LC assessment; reference found on The World List of Cycads and Crossref; Red List page not consulted (access blocked).]
  • Bösenberg, J.D. (2023). Cycas sexseminifera. The IUCN Red List of Threatened Species: e.T42084A69157287. doi:10.2305/IUCN.UK.2023-1.RLTS.T42084A69157287.en [Reassessment dated 2020; reference found on Crossref, LC category confirmed by GBIF; Red List page not consulted (access blocked).]
  • Haynes, J.L. (2022). Etymological compendium of cycad names. Phytotaxa 550(1): 1–31. doi:10.11646/phytotaxa.550.1.1 [Source of the etymologies given by The World List of Cycads; not consulted directly.]
  • 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; consulted directly.]