Macrozamia plurinervia

Macrozamia plurinervia is a small cycad with no visible trunk from northern New South Wales, in eastern Australia, where it grows as scattered plants in dry woodland on granite sands, between Inverell and Tenterfield. This species of the genus Macrozamia is recognised by its erect leaves whose axis spirals through three or four turns, set with stiff, fairly broad, many-veined leaflets. Long known as Macrozamia pauli-guilielmi subsp. plurinervia, the name given to it by L.A.S. Johnson in 1959, it was raised to species rank by David Jones in 1991. It is listed as Endangered by the IUCN.

Key facts about Macrozamia plurinervia

  • Accepted name: Macrozamia plurinervia (L.A.S.Johnson) D.L.Jones (1991), accepted by The World List of Cycads (version 2026.08.15) and the Australian Plant Census
  • Former names and synonyms: Macrozamia pauli-guilielmi subsp. plurinervia L.A.S.Johnson (1959, basionym)
  • Family: Zamiaceae, order Cycadales; section Parazamia
  • Common names: no English or Aboriginal name specific to the species is recorded
  • Natural range: northern New South Wales, Australia, roughly between Inverell and Tenterfield (Flora of Australia); The World List of Cycads also gives Queensland
  • IUCN status: Endangered (EN B1ab(ii,iii,v)+2ab(ii,iii,v)), assessment by J.D. Bösenberg dated 20 August 2020 and published in 2022
  • CITES and other protection: CITES Appendix II (annotation #4); Annex B in the European Union; not listed under the federal EPBC Act or in New South Wales
  • Documented hardiness: no cultivation data; in the wild, frequent frosts, with weekly July minima of about −4.7 °C (23.5 °F) at Inverell according to PACSOA (see Cold hardiness)
  • Light and soil: in the wild, dry woodland on sandy soils over granite, sometimes rocky slopes; in cultivation, a very free-draining soil
  • Habit and adult size: underground stem 20 to 30 cm across; 3 to 7 leaves (up to about 8) 85 to 115 cm long
  • In the UK, US and Australia: Royal Botanic Garden Sydney and Mount Annan (plants of wild origin); declared to BGCI by Glasgow Botanic Gardens, four American gardens and two other Australian gardens
  • Toxicity: no data for the species; the genus is very toxic to people and animals (see Toxicity and precautions)

How to recognise Macrozamia plurinervia

It is recognised by its fairly long leaves with a strongly spiralled axis, its dark green to grey-green leaflets, stiff, erect, with flat margins and paler beneath, and its cones held above the ground. Within the group of close species that also includes Macrozamia occidua and Macrozamia cranei, the Flora of Australia separates it by its robust habit, its longer leaves and petioles and its longer, stiff, erect leaflets. Its measurements are as follows.

  • Stem: underground, 20 to 30 cm across, usually unbranched.
  • Leaves: 3 to 7 in the crown, 85 to 115 cm long, moderately keeled, dark green to grey-green, semi-glossy; petiole 12 to 20 cm long; axis strongly spirally twisted.
  • Leaflets: 110 to 180 per leaf, simple, 10 to 30 cm long and 4 to 9 mm wide, clearly paler beneath, with flat or slightly incurved margins and an entire tip; the lowest leaflets are not reduced to spines.
  • Male cones: spindle-shaped, 18 to 28 cm long and 4 to 6 cm across.
  • Female cones: ovoid, 15 to 23 cm long and 6 to 9 cm across, with terminal spines 5 to 25 mm long.
  • Seeds: ovoid, 23 to 30 mm long and 23 to 26 mm wide, with red flesh.

David Jones (1991) added that its leaflets are broader, stiffer, thicker and of a dark, almost glaucous green, with a fairly abruptly narrowed tip, and that its cones are glaucous. The authors of the page of the Palm and Cycad Societies of Australia (PACSOA) add field details:

  • the axis usually makes three or four complete turns, mostly in its upper part, but it is barely twisted in some mature plants, and sometimes makes only one turn in small adults;
  • plants usually carry 3 to 5 leaves, up to about 8, sometimes only one or two;
  • young leaves are light green, with a yellow or reddish callus at the base of the leaflets; near Inverell, the calluses and the upper surface of the axis were bright yellow; with age the leaf turns mid-green and the callus creamy white;
  • the leaflets have a concave upper surface;
  • cones are usually solitary; female plants sometimes carry two, males up to three, at irregular intervals.

Hybrids

Natural hybrids have been reported, but under the older, broader definition of the species. L.A.S. Johnson (1959) cited probable hybrids with Macrozamia heteromera near Warialda, an apparent cross with Macrozamia stenomera (or perhaps Macrozamia heteromera), and transitional forms with other subspecies of Macrozamia pauli-guilielmi. David Jones (1991) wrote that he had found none of the intermediates mentioned by Johnson. No garden hybrid has been documented.

Possible confusion

It is easily confused with the other small Macrozamia with a spiralled axis from northern New South Wales and southern Queensland.

  • Macrozamia fawcettii: its closest relative according to PACSOA, also robust, with broad petioles, axes and leaflets.
  • Macrozamia flexuosa: more slender, with narrower petioles, axes and leaflets (PACSOA).
  • Macrozamia concinna: described in 1998 from plants formerly placed in subspecies plurinervia; smaller.
  • Macrozamia pauli-guilielmi: very narrow, deeply channelled leaflets; a coastal species of Queensland.
  • Macrozamia fearnsidei: from central Queensland, more robust, with leaflets up to 60 cm long, glossy and thin, and green cones (Jones, 1991).
  • Macrozamia machinii, Macrozamia occidua, Macrozamia cranei, Macrozamia conferta and Macrozamia viridis: small species of southern Queensland, described in 1994 within the same complex; only careful identification, together with the plant’s origin, separates them.

Taxonomy

Macrozamia plurinervia (L.A.S.Johnson) D.L.Jones is accepted by The World List of Cycads and the Australian Plant Census. It belongs to section Parazamia, that of the small species with an underground stem and no mucilage canals in the leaflets.

In his 1959 revision, L.A.S. Johnson divided Macrozamia pauli-guilielmi into three subspecies: pauli-guilielmi, flexuosa and plurinervia, which he described as new. He then conceived the last very broadly: from the far south of the Darling Downs (Queensland) to the lower Northern Tablelands, the north-western slopes and the upper Hunter Valley (New South Wales), in dry forest on stony slopes.

In 1991, in a paper in Austrobaileya that also described Macrozamia fearnsidei and Macrozamia lomandroides, David Jones explained that his visits near the type localities showed isolated populations, each tied to a habitat and with unique characters, and that he could not find the intermediates reported by Johnson. He therefore raised the three subspecies to species rank, creating the combination Macrozamia plurinervia.

The definition of the species has since narrowed. In 1994, David Jones and Paul Forster described seven new species from Queensland, most of them belonging to a “Macrozamia plurinervia complex” with fairly broad, shallowly channelled leaflets. In 1998, Macrozamia concinna was described for plants from the upper Hunter Valley and the Nundle district formerly placed in subspecies plurinervia. The same year, Ken Hill, in the Flora of Australia, restricted the species to the Inverell–Tenterfield area and treated Macrozamia machinii as a synonym; he considered that the complex needed further study. A note of 2026 in the online flora states that Macrozamia machinii is now accepted, following the Australian Plant Census. For the reader, this means that the name plurinervia, in books and collections earlier than 1998, may refer to plants now placed in other species.

The sources still differ on the range: the Flora of Australia mentions only New South Wales, but lists among its representative specimens a collection from Inglewood, in Queensland, the district where Macrozamia machinii was described; The World List of Cycads gives both New South Wales and Queensland.

Etymology and history

The epithet comes from the Latin pluri-, “several, many”, and nervus, “vein”, and refers to the leaflets, broader and with more veins than in neighbouring species (The World List of Cycads, after the works of Hill and Osborne, of Jones and of Whitelock). Johnson gave 6 to 10 veins for the broadest leaflets.

The type of the subspecies was collected in April 1956 by J. Leader on “Reedy Creek” station, near Bonshaw, in New South Wales (male holotype in the National Herbarium of New South Wales, Sydney, NSW 40958, with fragments of a female cone). Nothing is documented about its introduction into cultivation.

Common names

No English common name specific to the species is attested in published sources (The World List of Cycads, Flora of Australia, PlantNET, Species+, Atlas of Living Australia), and no Aboriginal name is recorded. Gardeners and botanists use the scientific name.

In the wild

According to the Flora of Australia and the flora of New South Wales (PlantNET), the species grows in northern New South Wales, roughly between Inverell and Tenterfield, as scattered plants in dry eucalypt woodland on sandy soils derived from granite. The representative specimens come notably from Emmaville and from Tarrangowen, near Ashford.

PACSOA describes it under a eucalypt canopy, in small colonies of scattered single plants or small groups, either on rocky slopes with poor gravelly soil or on flatter ground with sandy soil; near Inverell it grows on flat, sandy sites with an understorey of Callitris. For Inverell (584 m), the same source gives 764 mm of rain a year, 60 % of it in spring and summer, a minimum of −4.7 °C (23.5 °F) reached at least once a week in July, a maximum of 34.1 °C (93.4 °F) reached at least once a week in January, and frost on about 56 days a year. No study of the pollination of the species has been published.

Conservation status and regulation

Macrozamia plurinervia is listed as Endangered (EN) on the IUCN Red List under criteria B1ab(ii,iii,v)+2ab(ii,iii,v): its range and area of occupancy are small, fragmented or limited to few locations, with a continuing decline in area of occupancy, habitat quality and number of plants. The assessment, by J.D. Bösenberg, is dated 20 August 2020 and was published in 2022 (The World List of Cycads, GBIF and Crossref, checked on 26 October 2026). No listing under the federal Environment Protection and Biodiversity Conservation Act 1999 (EPBC) or in New South Wales appears in the Atlas of Living Australia (checked on 26 October 2026).

Like other Macrozamia, it has been listed in CITES Appendix II since 4 February 1977, with annotation #4: seeds and pollen are exempt, but plants are not. In the European Union it falls under Annex B of Regulation (EC) No 338/97, as amended by Regulation (EU) 2026/1383, applicable since 29 June 2026 (Species+, checked on 26 October 2026). Check the regulations in force, and the customs and plant-health rules, before any purchase abroad.

In practice, buy seed-grown plants of known origin, and be wary of old “plurinervia” labels, which may refer to other species.

Growing Macrozamia plurinervia

No reliable source describes the cultivation of this species: the advice below rests on its habitat and on the general rules for the genus.

Outdoor and in-ground cultivation

  • Soil: very free-draining, sandy or gravelly, like the granite sands and rocky slopes of its habitat.
  • Light: in the wild, under a light eucalypt canopy; a bright position suits it. Its tolerance of full sun in Europe is not documented.
  • Water: about 760 mm of rain a year in its region, mostly in spring and summer; water during growth, let the soil dry between waterings and avoid cold, waterlogged soil in winter.
  • Growth: no data for the species; small Macrozamia with an underground stem are generally very slow.

Container cultivation

No container culture has been described. A deep pot suits the underground stem; use a gritty, free-draining mix. In a pot the plant loses the protection that the soil gives the stem in winter.

In cultivation in the UK, US and Australia

  • Australia: the Royal Botanic Garden Sydney holds an accession of wild origin received in 2022 (S2022-0079); the Australian Botanic Garden Mount Annan lists three plants of wild origin from an accession of 2007 (A2007-0177), planted in a bed, and an accession of wild provenance numbered in 2023 (A2023-20830), according to their Garden Explorers. The Australian National Botanic Gardens (Canberra) and the North Coast Regional Botanic Garden (Coffs Harbour) also declare the species to BGCI.
  • United States: Marie Selby Botanical Gardens (Sarasota), Montgomery Botanical Center (Coral Gables), Naples Botanical Garden (all in Florida) and the University of California Botanical Garden at Berkeley declare it to BGCI. In Montgomery’s online catalogue, the entry “Macrozamia plurinervia” gives Macrozamia machinii as the accepted name (accessions numbered in 2023), which may mean plants received under one name and identified under the other. A BGCI declaration says that a garden has held the plant, not that a living specimen is there today.
  • United Kingdom: Glasgow Botanic Gardens declares it to BGCI (checked on 26 October 2026); whether the plant is grown under glass is not documented.

No grower in the English-speaking world has published a cultivation result.

Propagation

Propagation is by seed. Plants are male or female: both sexes are needed and, in cultivation, hand-pollination is required to obtain fertile seed. No germination data specific to the species have been published.

Pests and diseases

No problem specific to the species is documented. For Macrozamia grown in Europe, growers’ forums mainly mention scale insects and rot in cold, wet soil (see the genus page).

Cold hardiness

No cultivation report exists. In the wild, the species endures frequent frosts, with its stem protected by the soil.

Mediterranean and European experience

No cultivation of the species has been reported in Europe, in the ground or in a pot. On the French Fous de palmiers forum, in March 2014, a grower reported the opinion of an Australian nurseryman specialising in cycads, who ranked the species among the “relatively hardy” ones, with those of the New South Wales coast, without giving temperatures.

United Kingdom, United States and Australia

No dated report exists on the English-language forums that can be read. The climate of Inverell, as given by PACSOA (about 56 days of frost a year, a weekly July minimum around −4.7 °C, or 23.5 °F), shows only that the plant withstands repeated frosts in the wild, with an underground stem protected by the soil. The Bureau of Meteorology’s Inverell Research Centre station (664 m) records about ten days a year at or below 0 °C (32 °F) in the air and a lowest temperature of −5.5 °C (22.1 °F), on 26 June 1986. These figures describe the region, not the tolerance of the plant. In Britain and in the colder parts of the United States, a pot kept frost-free and dry in winter is the prudent choice.

Toxicity and precautions

No toxicity data specific to Macrozamia plurinervia have been published, but the risk is well documented for the genus, and the plant should be treated as very toxic, especially its seeds and young leaves. Macrozamia contain toxic glycosides (cycasin, macrozamin), from which methylazoxymethanol is derived, a powerful poison of the liver; cattle that eat the young leaves can develop a locomotor disorder of the hindquarters, the “zamia staggers”, which McKenzie (2006) describes as irreversible, with no treatment (see the genus page).

Wear gloves to handle the seeds, keep them out of reach of children, dogs and livestock, and contact a poison centre, a doctor or a vet without delay in case of ingestion.

Traditional uses

No use specific to Macrozamia plurinervia is documented. Asmussen’s (2011) review of the eating of Macrozamia seeds by Aboriginal peoples does not mention this species (see the genus page).

Frequently asked questions

Is it a subspecies of Macrozamia pauli-guilielmi?

Not any more. Johnson described it in 1959 as Macrozamia pauli-guilielmi subsp. plurinervia; David Jones raised it to species rank in 1991, and The World List of Cycads accepts it as Macrozamia plurinervia.

Why is its leaf axis twisted?

It is a character of the species. The leaf axis usually makes three or four complete turns, so that the leaflets seem to radiate all round it, like the branches of a tree; some mature plants, however, have a barely twisted axis.

How does it differ from Macrozamia fawcettii or Macrozamia flexuosa?

With difficulty. According to PACSOA, Macrozamia fawcettii is very close; Macrozamia flexuosa is more slender, with narrower petioles, axes and leaflets. The plant’s origin helps a great deal.

How hardy is it?

It has not been tested. No cultivation report exists; in the wild it endures about 56 days of frost a year, with minima around −4.7 °C (23.5 °F) every week in July, on a stem protected by the soil.

Is it endangered?

Yes. The IUCN lists it as Endangered (assessment published in 2022), because of a small, fragmented range and a decline in its habitat and in the number of plants.

Is it poisonous?

Probably, like all Macrozamia. No analysis specific to the species exists, but the seeds and young leaves of the genus are very toxic to people, pets and livestock.

Further reading on Succulentes

Sources

Reference sites

Bibliography

  • Johnson, L.A.S. (1959). The families of cycads and the Zamiaceae of Australia. Proceedings of the Linnean Society of New South Wales, ser. 2, 84(1): 64–117 (pp. 108–109 for this subspecies). [Description of Macrozamia pauli-guilielmi subsp. plurinervia, type, range, hybrids; full text (PDF made available by The World List of Cycads).]
  • Jones, D.L. (1991). Notes on Macrozamia Miq. (Zamiaceae) in Queensland with the description of two new species in section Parazamia (Miq.) Miq. Austrobaileya 3(3): 481–487. [Raising to species rank, distinction from neighbouring species, key; full text (BioStor).]
  • Jones, D.L. & Forster, P.I. (1994). Seven new species of Macrozamia section Parazamia (Miq.) Miq. (Zamiaceae section Parazamia) from Queensland. Austrobaileya 4(2): 269–288. [Macrozamia plurinervia complex; full text.]
  • Hill, K.D. (1998). Cycadophyta. In: McCarthy, P.M. (ed.), Flora of Australia 48: 597–661, 717–719. ABRS/CSIRO Publishing, Melbourne. [Description, range, taxonomic notes; online version.]
  • Bösenberg, J.D. (2022). Macrozamia plurinervia. The IUCN Red List of Threatened Species 2022: e.T41978A50524990. doi:10.2305/IUCN.UK.2022-1.RLTS.T41978A50524990.en [Endangered, criteria B1ab(ii,iii,v)+2ab(ii,iii,v); assessment dated 20 August 2020, from Crossref.]
  • Asmussen, B. (2011). “There is likewise a nut…” a comparative ethnobotany of Aboriginal processing methods and consumption of Australian Bowenia, Cycas, Macrozamia and Lepidozamia species. Technical Reports of the Australian Museum, Online 23(10): 147–163. doi:10.3853/j.1835-4211.23.2011.1575 [Aboriginal uses; the species is not mentioned.]
  • McKenzie, R.A. (2006). Toxicology for Australian Veterinarians: cycads (Cycas, Macrozamia, Lepidozamia, Bowenia), pp. 282–288. Animal Health Australia, Australian Animal Pathology Standards Program (PDF): https://aapspextranet.animalhealthaustralia.com.au/wp-content/uploads/2019/04/tav7_17_unknowntoxins_pt2.pdf [Australian veterinary reference text; describes the cattle syndrome as irreversible, ending in paralysis of the hindquarters, with no treatment.]
  • 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 list.]