Cycas semota

Cycas semota is a tree-like cycad from the far northern tip of Cape York Peninsula, in Queensland (Australia), known only from the Bamaga district, where it grows in the grassy understorey of eucalypt forest. This species of the genus Cycas was described in 1996 by the Australian botanist Ken Hill, who gave it a Latin name meaning “remote”, in reference to its position at the end of the continent. Its short megasporophylls and its soft, non-prickly cataphylls set it apart. The IUCN lists it as Vulnerable, and it is listed as Endangered under Queensland law.

Key facts about Cycas semota

  • Accepted name: Cycas semota K.D.Hill (1996), accepted by The World List of Cycads (version 2026.08.15) and by GBIF; POWO could not be consulted
  • Former names and synonyms: none; placed in the synonymy of Cycas angulata by de Laubenfels and Adema (1998), a treatment not followed
  • Family: Cycadaceae, order Cycadales
  • Common names: none attested, in English or in an Aboriginal language, in the sources consulted
  • Natural range: Australia, far northern Cape York Peninsula (Bamaga district, Queensland)
  • IUCN status: Vulnerable (VU, criterion D2 according to The World List of Cycads), assessment by J.D. Bösenberg published in Red List version 2022-1; VU according to GBIF
  • CITES and other protection: CITES Appendix II (seeds exempt under annotation #4); Annex B in the European Union; Endangered under the Queensland Nature Conservation (Animals/Plants) Regulation 2020; no federal (EPBC Act) listing recorded by WildNet
  • Documented hardiness: no data (see Cold hardiness)
  • Light and soil: in the wild, grassy understorey of fairly moist eucalypt forest, on shallow sandy soils over laterite; no cultivation data
  • Habit and adult size: trunk up to 4 m, rarely 5 to 6 m, 14 to 24 cm across; leaves 1.1 to 1.6 m long
  • In the UK, US and Australia: Montgomery Botanical Center (Florida), one accession of 1994; James Cook University, Townsville (declared to BGCI); no British record
  • Toxicity: no data specific to the species; treat it as poisonous, like all Cycas (see Toxicity and precautions)

How to recognise Cycas semota

Among the Australian cycads, Cycas semota is recognised by its short megasporophylls and by its short, soft cataphylls (the scale leaves that protect the growing point), which are not prickly and carry a very short, close-pressed down. These are the characters Hill (1996) stressed when he described it. The description below combines his original account and the Flora of Australia online, which give slightly different ranges.

  • Trunk: up to 4 m, rarely 5 to 6 m, 14 to 24 cm in diameter.
  • Leaves: glossy dark green (mid-green and semi-glossy according to the Flora of Australia), 1.1 to 1.6 m long, openly keeled (opposite leaflets set at 100 to 130° on the rachis), with 140 to 250 leaflets, ending in a pair of leaflets.
  • Petiole: 30 to 40 cm long, with loose orange-brown down, spiny on a short part of its length or not at all.
  • Median leaflets: 14 to 20 cm long and 6 to 7.5 mm wide, with slightly recurved margins and a tapering tip, set 8 to 11 mm apart.
  • Cataphylls: soft, 4 to 8 cm long, with a fine, silky grey-white down.
  • Male cones: unknown when the species was described; the Flora of Australia describes them as ovoid and brown, 40 to 46 cm long and 12 to 14 cm across, the microsporophylls ending in a spine 8 to 10 mm long.
  • Megasporophylls: grey-felted, carrying 2 to 8 ovules, with a regularly toothed blade and an apical spine 25 to 40 mm long according to the Flora of Australia (see below).
  • Seeds: flattened-ovoid, green turning orange, not powdery, 32 to 37 mm long and 28 to 32 mm wide.

The sources disagree on the megasporophylls, the key character. In the text of his 1996 description, Hill gives megasporophylls 10 to 14 cm long with a broadly triangular blade 50 to 65 mm long and 38 to 50 mm wide and 22 to 36 teeth; but the key in the same paper separates Cycas semota from Cycas tuckeri by longer megasporophylls, 13 to 20 cm, with a blade that is not dilated, 20 to 28 mm wide, figures that the Flora of Australia takes up (lance-shaped blade 60 to 75 mm by 20 to 28 mm, with 28 to 46 lateral spines). The figures of the 1996 description match those that the key gives for Cycas tuckeri, which suggests a slip in the description; the key and the Flora are followed here.

Hybrids

No hybrid is documented for this species.

Possible confusion

Its closest neighbour for the key character is Cycas tuckeri, from the Coen district farther south on the peninsula: its megasporophylls are even shorter, with a distinctly shorter and broader blade (Hill 1996; Flora of Australia). In the same region, Cycas yorkiana, of the same series, has keeled, yellowish-green leaves, a shorter petiole (15 to 30 cm) and a rachis ending in a spine. The type of Cycas normanbyana, now included in Cycas media, has a similarly tapering megasporophyll blade, but a much longer megasporophyll overall, and different cataphylls and leaflets.

Taxonomy

Cycas semota is a name accepted by The World List of Cycads and by GBIF; POWO could not be consulted. Hill described it in 1996 in his revision of the Australian cycads (Telopea 7(1): 23–26, fig. 11), from a type collected in the Bamaga district (Hill 4708 and Stanberg, 10 July 1994; holotype at the National Herbarium of New South Wales, NSW, with isotypes in seven other herbaria: BRI, CANB, DNA, K, L, MEL and NY). A much older collection by L.J. Brass, kept at Brisbane, Kew and Leiden, also belongs to the species according to the Flora of Australia.

Hill placed it in subsection Endemicae of section Cycas, and in series Yorkianosae, which he created in the same work: openly keeled to almost flat leaves, lower leaflets not reduced to spines, soft cataphylls, medium to large male cones, and a triangular megasporophyll blade with pungent teeth. In Australia the series includes Cycas badensis, Cycas semota, Cycas tuckeri and Cycas yorkiana, all from Cape York and the Torres Strait, and it has two species in New Guinea. De Laubenfels and Adema (1998) placed it in the synonymy of Cycas angulata, along with other northern Australian species; this treatment has not been followed.

Etymology and history

The epithet comes from the Latin semotus, “remote, distant”, in reference to the occurrence of the species in the farthest extremity of Cape York Peninsula (Hill 1996; Haynes 2022). No history of its introduction into cultivation is documented; the oldest accession found is at Montgomery Botanical Center, in Florida, dated 1994 by its number, the year in which Hill collected the type.

Common names

No common name is attested for this species, in English or in an Aboriginal language, in the sources consulted; the British nursery Trebrown knows of none.

In the wild

Cycas semota is locally abundant but apparently confined to the Bamaga district, at the northern tip of Cape York Peninsula. It grows in the grassy understorey of a relatively moist eucalypt forest, with Corymbia novoguinensis, Corymbia tessellaris and Erythrophleum chlorostachys, often in a mosaic with mesophyll forest, on shallow sandy soils over massive laterite (Hill 1996; Flora of Australia).

According to WildNet, the Queensland Government’s wildlife database, the male cones shed their pollen and the female plants are receptive in November and December, and pollination is carried out by small beetles in an obligate mutualism (species profile, consulted on 24 October 2026). The database treats its records of the species as confidential.

Conservation status and regulation

The IUCN lists Cycas semota as Vulnerable (VU) under criterion D2, which applies to species with a very small range or number of locations, in the assessment by J.D. Bösenberg published in version 2022-1 of the Red List, which replaces that of K.D. Hill (2010); the Red List data relayed by GBIF give the same category (consulted on 24 October 2026). In 1996 Hill stressed that all known collections came from a single population near the town of Bamaga, not conserved and under threat for that reason, and suggested the conservation code 2V-, describing it as a rare species, potentially at risk.

In Queensland, the species is listed as Endangered under the Nature Conservation (Animals/Plants) Regulation 2020, according to the Flora of Australia (November 2022 list) and WildNet, which also records an earlier “Critical” ranking under the state’s Back on Track programme (2008 to 2022) and no occurrence in a protected area. WildNet records no listing under the federal Environment Protection and Biodiversity Conservation Act 1999.

Like every species in the genus except Cycas beddomei, Cycas semota 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, names the species 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.

Growing Cycas semota

In short: it is held by a few botanic collections, but none has published growing advice, and no grower’s report has been found.

Outdoor and in-ground cultivation

The points below are deductions from its habitat, not documented results. A cycad of the monsoon tropics, growing in grassy eucalypt forest on shallow sand over laterite, it is likely to need warmth, good light and a free-draining, sandy soil, with water concentrated in the wet season. Outdoors, only frost-free tropical climates can be considered, such as northern Queensland or southern Florida.

Container cultivation

In the United Kingdom and other temperate regions, the only realistic option is a pot in a heated glasshouse, in a free-draining mix. No European experience exists.

In cultivation in the UK, US and Australia

In short: one American collection and one Australian university, nothing in Britain.

  • United States: Montgomery Botanical Center, in Coral Gables (Florida), lists one accession in its online catalogue, number 941305, dated 1994 by its number (consulted on 24 October 2026).
  • Australia: James Cook University, at its Townsville campus, declares the species to BGCI; such a declaration shows that the plant was held at some point, not that it is alive today.
  • United Kingdom: no record in BGCI or in the British catalogues checked in October 2026.

Elsewhere, BGCI lists the Prague Botanical Garden. The British nursery Trebrown gives the species a USDA zone 9b rating, its own commercial classification, not a documented trial. No report from a private grower was found.

Propagation

The plant is dioecious: seed requires a male and a female plant, and in the wild pollination depends on small beetles (WildNet). In cultivation, hand pollination would be needed if the insects are absent. No germination data specific to the species have been published. Seeds are exempt from CITES under annotation #4; look only for seed of legal, documented origin, the species being protected in Queensland.

Pests and diseases

No pest or disease specific to the species is documented. 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 cold-tolerance data exist for Cycas semota. Northern Cape York has a frost-free tropical climate, and nothing suggests that the plant can take frost.

Mediterranean and European experience

No cultivation result has been published in Europe, in the open ground or in a pot, and no dated frost episode concerns this species.

United Kingdom, United States and Australia

No cold reading was found in any country. The only figure available is Trebrown’s commercial zone 9b rating, which is not based on a published trial. Treat it as a frost-tender plant: a heated glasshouse in the UK, frost-free tropical gardens elsewhere.

Toxicity and precautions

No toxicity study specific to Cycas semota 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. In the absence of evidence to the contrary, 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 use is documented for this species in the sources consulted.

Frequently asked questions

What does semota mean?

“Remote” in Latin: the name recalls that the species lives at the northern tip of Cape York Peninsula.

Where does Cycas semota grow?

Only in the Bamaga district, at the tip of Cape York (Queensland), in the grassy understorey of eucalypt forest on sandy soils over laterite.

How does it differ from Cycas tuckeri?

By its longer megasporophylls with a longer, narrower blade; those of Cycas tuckeri, from the Coen district, are even shorter, with a short, broad blade.

How big does it grow?

Up to 4 m of trunk, rarely 5 to 6 m, 14 to 24 cm across, with leaves 1.1 to 1.6 m long.

Is it endangered?

Yes. The IUCN lists it as Vulnerable and Queensland as Endangered: it is known from a single district, and in 1996 its only known population was not protected.

How is it pollinated?

By small beetles, in an obligate mutualism, with pollen shed and female cones receptive in November and December, according to the Queensland Government.

Is it hardy?

No, as far as anyone can tell. No cold data exist and its native climate is frost-free: in the UK, grow it in a heated glasshouse.

Further reading on Succulentes

Sources

Reference sites

Bibliography

  • Hill, K.D. (1996). A taxonomic revision of the genus Cycas (Cycadaceae) in Australia. Telopea 7(1): 1–64. doi:10.7751/telopea19963040 [Original description (pp. 23–26, fig. 11), key, series Yorkianosae, conservation status; full text consulted.]
  • Hill, K.D. (1998). Cycadaceae. In: McCarthy, P.M. (ed.), Flora of Australia 48: 597–635. CSIRO Publishing, Melbourne. [Consulted in its updated online version (profiles.ala.org.au).]
  • Bösenberg, J.D. (2022). Cycas semota. The IUCN Red List of Threatened Species: e.T41975A69157091. doi:10.2305/IUCN.UK.2022-1.RLTS.T41975A69157091.en [Current assessment (dated 2020); reference found on The World List of Cycads and Crossref, VU category confirmed by GBIF; Red List page not consulted (access blocked).]
  • Hill, K.D. (2010). Cycas semota. The IUCN Red List of Threatened Species: e.T41975A10588336. [Previous assessment; reference found on Crossref; Red List page not consulted (access blocked).]
  • de Laubenfels, D.J. & Adema, F. (1998). A taxonomic revision of the genera Cycas and Epicycas gen. nov. (Cycadaceae). Blumea 43(2): 351–400. [Synonymy with Cycas angulata (p. 363); cited from The World List of Cycads and the Flora of Australia.]
  • 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.]