Cycas terryana

Cycas terryana is a tree-like cycad of central-eastern Queensland, in Australia, known from five populations in the Broadsound and Connors ranges, between Marlborough and St Lawrence, where it grows on granite hills in open woodland. Described in 2011 by Paul Forster, this species of the genus Cycas had long been regarded as a hybrid swarm between Cycas media and Cycas ophiolitica. It is recognised by its very brittle leaves and the pale fawn down on its new growth. The IUCN lists it as Vulnerable.

Key facts about Cycas terryana

  • Accepted name: Cycas terryana P.I.Forst. (2011), accepted by The World List of Cycads (version 2026.08.15) and by GBIF; POWO could not be consulted
  • Former names and synonyms: no synonym; its populations were previously treated as hybrids or intergrades between Cycas media and Cycas ophiolitica (Hill 1992, 1996)
  • Family: Cycadaceae, order Cycadales
  • Common names: none attested
  • Natural range: Australia, Queensland: Broadsound and Connors ranges, north-west of Marlborough and south-west of St Lawrence
  • IUCN status: Vulnerable (VU B1ab(ii,iii,v)), assessment by P.I. Forster dated 2020 and published in Red List version 2023-1; Vulnerable in Queensland (Nature Conservation (Animals/Plants) Regulation 2020)
  • CITES and other protection: CITES Appendix II (seeds exempt under annotation #4), as for the whole family; Annex B in the European Union; the name is not yet listed by Species+
  • Documented hardiness: no measured or reported value (see Cold hardiness)
  • Light and soil: open eucalypt and Corymbia woodland, on low hills with stony soils derived from porphyritic granite
  • Habit and adult size: trunk up to 3 m tall and 12 to 22 cm thick; leaves 0.8 to 1.9 m long
  • In the UK, US and Australia: James Cook University, Townsville (declared to BGCI); no British or American record
  • Toxicity: no data specific to the species; treat it as poisonous, like all Cycas (see Toxicity and precautions)

How to recognise Cycas terryana

By its brittle leaves and pale down. Paul Forster (2011) separates it from its two neighbours by its very brittle leaves and rachis, which snap easily, by the pale grey-fawn to fawn-tan down on its new growth, cataphylls and megasporophylls (orange-brown in the related species) and by its generally broader megasporophylls. The description below is the original one.

  • Trunk: up to 3 m tall, rarely with several heads, 12 to 22 cm thick.
  • Leaves: 80 to 190 cm long, straight and then wavy towards the tip, weakly to strongly keeled, light green to grey-green and somewhat glaucous; rachis hairy, usually ending in a pair of leaflets; petiole 17 to 30 cm, grey to olive-green, with 4 to 40 small teeth 1.5 to 2 mm long, sometimes unarmed.
  • Leaflets: 184 to 320 per leaf, 7 to 10 mm apart, brittle, with recurved margins; mid-leaf leaflets 105 to 230 mm long and 5 to 7 mm wide, grey-green, with a fawn bloom when young. New growth densely covered in creamy to pale fawn down, which is later shed.
  • Cataphylls: linear, pungent, 8 to 12 cm long, entirely covered in pale fawn down.
  • Male cones: elongated-ovoid, 21 to 28 cm long and 6.5 to 8 cm wide, densely covered in reddish-brown down; microsporophylls 28 to 40 mm long, with an upturned apical spine of 4 to 10 mm.
  • Megasporophylls: 20 to 33 cm long, densely fawn-felted when young, then grey and finally hairless and olive-green; 4 to 6 ovules; blade broadly triangular, 50 to 70 mm long and 30 to 38 mm wide, strongly toothed (teeth 4 to 7 mm); apical spine 17 to 33 mm.
  • Seeds: ovoid, 37 to 40 mm long and 30 to 35 mm across; sarcotesta about 5 mm thick, faintly grey-bloomed, olive-green beneath the wax, orange when ripe.

Hybrids

The question of hybrids lies at the heart of this species’ history. Ken Hill (1992, 1996) saw these populations as intergrades between Cycas media and Cycas ophiolitica, with the wide variation expected of successive hybrid generations. Paul Forster (2011) disputes this reading: no population of either supposed parent grows nearby (the closest Cycas media is about 9 km away, on a different geology, and the closest Cycas ophiolitica about 45 km away), and the plants form healthy, distinct populations on a substrate of their own. Forster accepts that an ancient mixing of lineages may have preceded speciation through isolation, but regards the species as well differentiated. No published genetic study has settled the matter.

Possible confusion

  • Cycas ophiolitica, from the serpentinite country around Marlborough: robustly flexible (not brittle) leaves, much more strongly keeled and glaucous when young, orange-brown down.
  • Cycas media (subspecies media): leaves only weakly brittle, flat to weakly keeled and hairless at maturity, cataphylls with orange-brown down.

Taxonomy

Cycas terryana is an accepted name in The World List of Cycads; POWO could not be consulted. Paul I. Forster, of the Queensland Herbarium, described it in 2011 (Austrobaileya 8(3): 356–363, plate 1, figs 1–4). In the same paper he criticises Hill’s readiness to interpret many Cycas populations as hybrids, an idea that in his view should be tested with molecular markers. He also questions the value of Hill’s series, since Cycas media and Cycas ophiolitica, placed in different series, would share a possible descendant. The World List of Cycads notes that Hill (1992) regarded these populations as a hybrid swarm.

Etymology and history

The species honours Dr L. Irene Terry, of the University of Utah, for her pioneering work on cycad pollination in Australia and on Guam (Forster 2011; Haynes 2022).

The plant seems to have been collected first by Selwyn Everist in March 1964 in the Broadsound Range; that specimen was identified at different times as Cycas media and as an intergrade between Cycas media and Cycas ophiolitica (determination by K.D. Hill). The type was collected on 9 March 2005 in the Broadsound Range by P.I. Forster and P.J. Machin (Forster & Machin PIF30618; holotype at the Queensland Herbarium, Brisbane). Forster also cites collections made in 1981, 1990 and 1992, and from 2003 to 2011.

Common names

No common name is attested for this species, in English or in any other language, in the sources consulted.

In the wild

Cycas terryana is confined to the Broadsound and Connors ranges, north-west of Marlborough and south-west of St Lawrence. It grows on undulating low hills with stony soils derived from heavily weathered porphyritic granite, in woodland dominated, depending on the site, by Corymbia clarksoniana, Corymbia dallachiana, Eucalyptus crebra, Eucalyptus drepanophylla and Petalostigma pubescens. Five populations are known, over an extent of occurrence of about 800 km², in a region that botanists have explored little (Forster 2011).

Conservation status and regulation

The IUCN lists Cycas terryana as Vulnerable (VU) under criteria B1ab(ii,iii,v): a small range, with a continuing decline in the area occupied, the quality of the habitat and the number of mature plants. The World List of Cycads does not give the year of the assessment; Crossref identifies it as the assessment by P.I. Forster, dated 2020 and published in Red List version 2023-1, and GBIF relays the VU category. The Red List itself could not be consulted. As early as 2011, Forster recommended Vulnerable under criterion D2: none of the populations was in a conservation reserve, and at least one had been reduced to a number of plants too small to be viable.

In Queensland, the state’s WildNet database lists the species as Vulnerable under the Nature Conservation (Animals/Plants) Regulation 2020 (a listing recorded in April 2025), as a restricted plant, and as a confidential taxon whose locations are not published. WildNet also flags the species as recorded within a protected area, without naming it, whereas Forster reported in 2011 that no population lay in a conservation reserve. No listing under the national EPBC Act appears in WildNet.

Like every species in the genus except Cycas beddomei, Cycas terryana is covered by CITES Appendix II, where the family Cycadaceae has appeared since 4 February 1977. The listing carries annotation #4 (the version adopted at CoP20, in force since 5 March 2026): seeds, pollen, seedlings and tissue cultures obtained in vitro and transported in sterile containers, as well as cut flowers of artificially propagated plants, are not covered by CITES; international trade in plants requires an export permit. In the European Union the species falls under Annex B of Regulation (EC) No 338/97, whose current annexes are set by Regulation (EU) 2026/1383, applicable since 29 June 2026. Species+, the official CITES database, does not yet list this name, published in 2011 (search of 24 October 2026): the protection comes from the listing of the whole family, which covers every species, named or not.

This summary does not replace the official texts: check the regulations in force before any purchase or exchange, ask the seller for proof of origin and choose nursery-raised plants grown from seed.

Growing Cycas terryana

No cultivation guidance has been published by an institution, and no cultivation report was found on English-, French- or Italian-language forums. The points below are inferences from the habitat, not tested results: a plant of granite hills in seasonally dry woodland is likely to want full sun and a stony, very free-draining soil.

Outdoor and in-ground cultivation

Outdoors, only climates close to its own, warm and with little or no frost, can reasonably be considered, such as coastal Queensland and comparable subtropical regions. No planted specimen with a documented history outside its range has been found.

Container cultivation

In cooler regions, a pot kept frost-free in winter, in a mineral, free-draining compost and in full light, is the prudent option. Australian Cycas in general have a reputation in Europe for declining on their own roots, mainly through root rot in cool, wet spells; for this species, however, there is no documented experience.

In cultivation in the UK, US and Australia

In short: one Australian record, and none in Britain or the United States.

  • Australia: James Cook University, on 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 States: no accession in the online catalogue of Montgomery Botanical Center and no American garden in BGCI (both consulted on 24 October 2026).
  • United Kingdom: no record in BGCI or in the British catalogues checked in October 2026; the British nursery Trebrown has no page for it.

Elsewhere, BGCI lists only the Botanical Garden of the Ruhr University Bochum, in Germany. No report from a private grower was found; PalmTalk and Dave’s Garden could not be consulted.

Propagation

The plant is dioecious: a male and a female are needed to obtain seed. No germination data specific to the species has been published; Cycas seed is usually sown fresh, in a free-draining mix and in warmth. Seeds are exempt from CITES under annotation #4: ask for seed from cultivated plants.

Pests and diseases

No pest or disease specific to the species has been documented.

Cold hardiness

No cold-hardiness value has been measured or reported for Cycas terryana. A seed company’s description of it as tolerant of light frosts could only be seen as a search-engine excerpt, the page itself being unreachable, and it gives no figure: it is not used here.

Mediterranean and European experience

No result has been published from southern France or Italy, outdoors or in a pot: a search of the French Fous de palmiers forum and of the Italian Tropicamente forum returned nothing, and the Jardin zoologique tropical at La Londe-les-Maures, in the Var, has published no observation of this species.

United Kingdom, United States and Australia

No cold value and no dated cultivation report was found, from forums or from botanic gardens.

Toxicity and precautions

No toxicity analysis specific to Cycas terryana 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 the plant 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 of this species is documented in the sources consulted.

Frequently asked questions

Who was Terry?

Dr L. Irene Terry, a researcher at the University of Utah who specialised in cycad pollination in Australia and on Guam.

Where does Cycas terryana grow?

In the Broadsound and Connors ranges of central-eastern Queensland, on granite hills in open woodland.

Is it a hybrid?

No, according to its author and to The World List of Cycads. Ken Hill saw hybrids of Cycas media and Cycas ophiolitica in these populations; Paul Forster described them as a species in 2011, and no genetic study has yet tested either view.

How can I recognise it?

By its very brittle leaves and the pale fawn down on its new growth and cataphylls.

Is it endangered?

Yes. It is listed as Vulnerable by the IUCN and in Queensland: five populations are known.

Is it hardy in the UK?

Nothing shows that it is. No cold value has been published and no trial is known: in Britain it should be treated as a glasshouse plant.

Can it be grafted onto Cycas revoluta?

This is not documented. A French nursery offers other Australian Cycas grafted onto Cycas revoluta (see Further reading), but no source mentions Cycas terryana.

Is it poisonous?

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

Further reading on Succulentes

Sources

Reference sites

Bibliography

  • Forster, P.I. (2011). Cycas terryana P.I.Forst. (Cycadaceae), a new species from central Queensland. Austrobaileya 8(3): 356–363. doi:10.5962/p.299813 [Original description, specimens, habitat, populations, proposed status; full text consulted (BioStor, archive.org).]
  • Hill, K.D. (1992). A preliminary account of Cycas (Cycadaceae) in Queensland. Telopea 5(1): 177–206. doi:10.7751/telopea19924964 [Populations treated as media × ophiolitica intergrades; full text consulted.]
  • Hill, K.D. (1996). A taxonomic revision of the genus Cycas (Cycadaceae) in Australia. Telopea 7(1): 1–64. doi:10.7751/telopea19963040 [Reference revision for Australia; full text consulted.]
  • Forster, P. (2023). Cycas terryana. The IUCN Red List of Threatened Species 2023-1: e.T66910064A66910102. doi:10.2305/IUCN.UK.2023-1.RLTS.T66910064A66910102.en [Assessment dated 19 November 2020; reference checked on Crossref, VU category relayed 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 etymology 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.]