Zamia prasina

Zamia prasina is a cycad with an underground stem from Belize, the Petén region of Guatemala and south-eastern Mexico, where it occupies the Yucatán Peninsula and its surroundings, from savannas to tropical forest. This species of the genus Zamia was long known as Zamia polymorpha, the name under which it was described in 1998 and which stressed its extreme variability; in 2009 it was shown that an older name, Zamia prasina, published in 1881 by an English nurseryman, referred to the same plant. In the meantime the name Zamia prasina had been wrongly applied to another Belizean species, now Zamia decumbens. The IUCN rates it Least Concern.

Key facts about Zamia prasina

  • Accepted name: Zamia prasina W.Bull (1881), accepted by The World List of Cycads (version 2026.08.15), by GBIF and by the World Checklist of Vascular Plants, on which POWO is based; POWO could not be consulted directly
  • Former names and synonyms: Zamia polymorpha D.W.Stev., A.Moretti & Vázq.Torres (1998); the name Zamia prasina was long misapplied to Zamia decumbens
  • Family: Zamiaceae, order Cycadales
  • Common names: no English name; “mata ratón” in Spanish, in the Maya region (Fedick and Santiago, 2022, as Zamia polymorpha)
  • Natural range: Belize (Belize, Cayo, Orange Walk, Stann Creek and Toledo districts), Guatemala (Petén), Mexico (Campeche, Chiapas, Tabasco, Quintana Roo, Yucatán), according to The World List of Cycads; from sea level to 200 m in Mexico, up to 500 m in Belize
  • IUCN status: Least Concern (LC), assessment published in 2022
  • CITES and other protection: CITES Appendix II (whole genus, since 1977; seeds exempt under annotation #4); Annex B in the European Union; in Mexico, “subject to special protection” under the NOM-059-SEMARNAT-2010 standard
  • Documented hardiness: no measurement for the species (see Cold hardiness)
  • Light and soil: from savannas in full sun to the understorey of tropical forest; clay or rocky soils rich in organic matter; in cultivation, according to a French specialist nursery, a free-draining, slightly limy or neutral compost
  • Habit and adult size: underground stem up to 10 cm across; 1 to 4 leaves 0.5 to 1.5 m long, with 3 to 12 pairs of leaflets (description of Zamia polymorpha)
  • In the UK, US and Australia: Montgomery Botanical Center, Fairchild Tropical Botanic Garden and other American gardens; Cairns Botanic Gardens (Australia, as Zamia polymorpha); no British record
  • Toxicity: no data specific to the species; treat it as poisonous (see Toxicity and precautions)

How to recognise Zamia prasina

It is a Zamia with an underground stem and a few leaves bearing leathery leaflets, toothed in their upper part, but very variable in appearance from one plant to another. The fullest description is that of Zamia polymorpha, published in 1998 by Dennis Stevenson and the Neapolitan botanists Aldo Moretti and Luciano Gaudio in the journal Delpinoa:

  • Stem: underground, almost globose, up to 10 cm across; cataphylls ovate, 3 to 4 cm by 1.5 to 2.5 cm.
  • Leaves: 2 or 3 (1 to 4), erect, 0.5 to 1.5 m long; petiole 15 to 50 cm, slightly to very prickly; rachis with 3 to 12 pairs of leaflets.
  • Leaflets: lanceolate to oblanceolate, wedge-shaped at the base, acute to almost acuminate at the tip, with a toothed margin in the upper two-thirds; the largest, in the middle of the leaf, 20 to 30 cm by 2 to 8 cm.
  • Male cones: tan, cylindrical to ovoid-cylindrical, 6 to 10 cm by 2 to 4 cm, on a peduncle of 2 to 4 cm; scales with a sterile tip of six slightly sloping facets around a small, sunken central facet.
  • Female cones: tan to brown, cylindrical to ovoid-cylindrical, 10 to 15 cm by 5 to 7 cm, ending in an acute, gradually tapering sterile tip.
  • Seeds: light red to red, 1.5 to 2 cm by 0.5 to 0.8 cm.
  • Chromosomes: number varying between plants, 2n = 17 and 22 to 28.

The name polymorpha, “of many forms”, comes from this variability. According to the 1998 authors, plants, or even single leaves, in full sun are shorter and narrower, leathery, with finely toothed lanceolate leaflets; those in deep shade have longer, broader leaves, subcoriaceous to papery, with elliptic to almost oblanceolate leaflets; both extremes have been seen on the same plant. In 2008, however, Calonje and Meerman found in Belize consistent populations, with narrow leaflets in the savannas and large leaves in the forests, as well as narrow-leaflet plants that kept their shape after years in shade: the variability therefore seems at least partly genetic. A 2016 study (Limón and colleagues) deals with the effect of environmental heterogeneity on this variation.

William Bull’s original description (1881), quoted by Calonje and Meerman (2009), speaks of a cycad “introduced from Honduras” (British Honduras, now Belize), with cylindrical petioles bearing a few small white prickles, sixteen or seventeen pairs of oblanceolate leaflets, entire but finely toothed towards the tip, of a bright grass green above, hence its name.

Hybrids

No named hybrid is documented. According to Calonje and Meerman (2009), the species of the complex to which it belongs, that of Zamia loddigesii, are highly variable and may hybridise readily (Schutzman, 1987); no natural hybrid involving Zamia prasina has been described.

Possible confusion

It is one of the most confusing Zamia, because of both its variable appearance and the history of its name:

  • Zamia decumbens, of the sinkholes of the Maya Mountains in Belize: this is the plant to which horticulture and the literature long gave the name “Zamia prasina”. According to Calonje and Meerman (2009), it has a decumbent above-ground stem and papery, gradually acuminate leaflets with a raised longitudinal fold and an entire or barely toothed tip; Zamia prasina has an underground stem and leathery, abruptly acuminate leaflets without a fold, strongly toothed in the upper half;
  • Zamia loddigesii, of the coastal plain of the Gulf of Mexico: before 1998, the plants of Yucatán and Belize were included in it. The two species are alike in habit and leaves, but Zamia loddigesii has brown male cones and a grey to very pale tan, cylindrical female cone with a long, constricted sterile tip, and a fixed chromosome number (2n = 18); the key by Nicolalde-Morejón and colleagues (2024) separates them by the colour of the female cone (cream to yellowish in Zamia loddigesii, brown in Zamia prasina) and by region;
  • Zamia furfuracea: some plants of Zamia prasina resemble it in the shape and texture of the leaflets, but lack both the down that covers the adult leaflets of Zamia furfuracea and its obovate leaflets (1998 description);
  • Zamia lawsoniana, of Mexico: according to Nicolalde-Morejón and colleagues (2024), Zamia prasina differs in its oblong to oblanceolate leaflets more than 4 cm wide;
  • Zamia variegata, also found in Belize: leaflets also strongly toothed, but papery and speckled with yellow (Calonje and Meerman, 2009).

In Tabasco, Nicolalde-Morejón and colleagues (2024) also mention Zamia katzeriana and Zamia cremnophila, which grow on karst rocks in evergreen forest and are recognised by their pink-red or reddish-brown young leaves.

Taxonomy

Zamia prasina W.Bull is an accepted name according to The World List of Cycads, GBIF and the World Checklist of Vascular Plants, on which POWO is based (read on GBIF, which cites “Nursery Cat. (William Bull) 176: 20 (1881)” and lists Zamia polymorpha as a synonym); POWO itself could not be consulted. The name was published in 1881 by the English nurseryman William Bull in his sales catalogue (Retail List no. 176, page 20), at a price of one and a half guineas: an unusual medium, but sufficient to publish a name. Bull supplied a leaf to Kew, later mounted as a herbarium specimen; in 1884 William Turner Thiselton-Dyer tentatively referred it, with a question mark, to Zamia latifolia, and in 1932 Julius Schuster placed it in the synonymy of Zamia loddigesii var. latifolia, dating the catalogue to 1822 instead of 1881 by mistake. The name then fell into oblivion, Bull’s original description and leaf being found again only in 1998 (Whitelock, 2002, quoted by Calonje and Meerman).

In 1998 Stevenson, Moretti and Gaudio described Zamia polymorpha (a name attributed to Stevenson, Moretti and Mario Vázquez Torres) in the journal Delpinoa (volumes 37–38, dated 1995–1996), from eleven populations studied in 1988 in Belize and Yucatán, at first taken for Zamia loddigesii. They separated it on cytology, morphology, geography and climate. The holotype was collected on 22 January 1989 in Cayo District, Belize (Stevenson and colleagues 1119, New York).

Meanwhile the name Zamia prasina had been applied to a rare plant of the Maya Mountains. In 2009 Michael Calonje and Jan Meerman, in the article “What is Zamia prasina?”, re-examined the historical material at Kew and the populations of Belize: in a very variable population halfway between Belmopan and Belize City they found plants identical to Bull’s leaf, to the drawing kept at Kew and to the holotype of Zamia polymorpha. They concluded that Zamia prasina is the oldest valid name for Zamia polymorpha, which becomes a synonym, and designated the Kew leaf (Bull s.n., 22 March 1881) as lectotype. The Maya Mountains plant was described in the same issue of the journal as Zamia decumbens. The authors nevertheless recommended genetic studies to clarify the relationships between the different forms of the species within the Zamia loddigesii complex, which also includes Zamia paucijuga and Zamia spartea.

The transcriptome-based study by Lindstrom and colleagues (2024), which sampled a plant from Cayo District, places Zamia prasina with Zamia variegata in subclade III-A, that of the species of south-eastern Mexico, whose range extends into Belize and Guatemala.

Etymology and history

The epithet comes from the Latin prasinus, “leek-green”, and refers to the grass-green leaflets (The World List of Cycads, after Haynes, 2022).

A letter of June 1881 kept at Kew with a drawing of the plant tells that Bull had received two consignments of Zamia from Belize, of which few plants had survived, and that a Kew employee had “extracted” two plants from him that he wished to recover (Calonje and Meerman, 2009). The same authors also recall that in 1883 D. Morris reported the species as common on ridges and banks near Point Ycacos, and describe it as the commonest cycad in Belize, no doubt the first that Bull’s collectors came across.

Common names

No English name is attested. A study of Maya food plants (Fedick and Santiago, 2022) calls Zamia polymorpha “mata ratón”, a Spanish name meaning roughly “rat killer”. No other common name is attested.

In the wild

According to The World List of Cycads, Zamia prasina grows in Belize (Belize, Cayo, Orange Walk, Stann Creek and Toledo districts), in the Petén of Guatemala and in south-eastern Mexico (Campeche, Chiapas, Tabasco, Quintana Roo and Yucatán). The 1998 description called it endemic to the Yucatán Peninsula and the east coast of Belize, up to 500 m on the eastern slopes of the Maya Mountains; in Mexico, Nicolalde-Morejón and colleagues (2014) give an altitude of 0 to 200 m. A Neapolitan study of 2006 (Napolitano and colleagues) speaks of populations scattered along about 1,000 km of coast.

The species grows both in savannas, where narrow-leaflet forms predominate, and in seasonal evergreen tropical forest, where the leaves are larger (Calonje and Meerman, 2009). Nicolalde-Morejón and colleagues (2024) describe it in semi-deciduous tropical forest, from sea level to 200 m, on clay and rocky soils rich in organic matter. Neither the pollinators nor the phenology of the species are documented.

Conservation status and regulation

Zamia prasina is rated Least Concern (LC) on the IUCN Red List, in the assessment by J.D. Bösenberg published in 2022 (The World List of Cycads; category confirmed by GBIF; the Red List page could not be consulted). Older assessments published under the name Zamia prasina must be read with caution, because the name then referred to the Maya Mountains plant: in the 2003 IUCN action plan, “Zamia prasina” (Belize) was rated Critically Endangered (CR), with fewer than 100 plants, whereas Zamia polymorpha (Mexico, Belize) was considered Near Threatened (NT), with about 10,000 stable plants.

In Mexico the species is “subject to special protection” (Pr) under the NOM-059-SEMARNAT-2010 standard (Nicolalde-Morejón and colleagues, 2014). In 2022 Fedick and Santiago described it as a “rare” cycad, whereas Calonje and Meerman described it in 2009 as the commonest in Belize.

Like all Zamia except Zamia restrepoi, which is in Appendix I, Zamia prasina is covered by the listing of the genus in CITES Appendix II, in force since 4 February 1977. Annotation #4 exempts seeds, pollen, seedlings and tissue cultures obtained in vitro and transported in sterile containers; international trade in the plants themselves requires an export permit from the country of origin. In the European Union the species falls under Annex B of Regulation (EC) No 338/97, whose current list is set by Regulation (EU) 2026/1383, applicable since 29 June 2026. Species+ has its own entry for Zamia prasina, with Zamia polymorpha as a synonym, which confirms this status (checked on 11 October 2026).

This general information does not replace the official texts: check the regulations in force before buying or exchanging plants or seeds, ask the seller for proof of origin and prefer plants raised from cultivated seed.

Growing Zamia prasina

The species has long been grown in botanic gardens: the 1998 description cites plants at Fairchild Tropical Garden in Miami; the botanic garden of Naples grew many plants collected in Belize and Mexico, studied for their chromosomes (Napolitano and colleagues, 2006); in Belize, the Green Hills Botanical Collections keep savanna plants (Calonje and Meerman, 2009). No growing recommendation specific to the species has been published.

Simon Lavaud, of the French specialist nursery Cycadales.eu, places Zamia prasina in his group of Zamia from Mexico, Guatemala, El Salvador and Honduras, of “medium” difficulty: species that mostly come from climates with a marked dry season and tolerate dry air and a fairly dry compost in winter. For this group he recommends:

  • a free-draining compost, slightly limy or neutral; any type of water;
  • in winter, 5 to 10 °C (41 to 50 °F) with daytime rises to 20 to 25 °C (68 to 77 °F); a medium tolerance of prolonged cool spells, with the compost fairly dry but never completely parched;
  • in summer, 15 to 20 °C (59 to 68 °F) at night and 25 to 30 °C (77 to 86 °F) by day, up to 40 °C (104 °F) with generous watering;
  • at least four to six months a year of summer temperatures.

These are recommendations from experience for a group of species, not trials with Zamia prasina (Lavaud, 2023). Its tolerance of both full sun and shade, documented in the wild, changes the shape of the leaves: short and narrow in sun, broad in shade.

On the French forum Fous de palmiers, a grower offered for exchange in 2009 two seedlings sold as Zamia prasina, raised from seed from Fairchild Tropical Garden; in 2011 the same member reported sowing 30 cheap seeds bought under this name, with no germination at all. At that time the name was still applied in the trade to the Maya Mountains plant (Zamia decumbens): the identity of these plants cannot be checked.

Outdoor and in-ground cultivation

No outdoor result has been published outside the tropics. In frost-free tropical and subtropical climates, the species’ range of habitats, from open savanna to forest, suggests a free-draining soil in sun or partial shade; elsewhere it is a plant for a warm glasshouse or conservatory.

Container cultivation

Its underground stem and few leaves suit a pot. Use a mineral, free-draining compost, give it full summer warmth, and overwinter it frost-free, at 5 to 10 °C (41 to 50 °F) at least, with the compost on the dry side, as advised for the Mexican and Central American Zamia group.

In cultivation in the UK, US and Australia

In short: present in several American gardens, recorded in one Australian garden, absent from British records.

  • United States: Montgomery Botanical Center (Coral Gables, Florida) lists thirteen accession numbers in its online catalogue, from 1993 to 2009 according to their numbers; BGCI also records it at Fairchild Tropical Botanic Garden (Miami), Naples Botanical Garden and Marie Selby Botanical Gardens (Florida), The Huntington (San Marino) and San Diego Botanic Garden (California), Atlanta Botanical Garden, the National Tropical Botanical Garden and the University of Hawaii at Hilo botanical garden (catalogues and BGCI queried on 25 October 2026).
  • Australia: Cairns Botanic Gardens (Queensland), under the name Zamia polymorpha, according to BGCI.
  • United Kingdom: no record in BGCI; Kew holds the lectotype, a herbarium leaf supplied by Bull in 1881.

A BGCI declaration shows that a garden held the plant at some point, not that it is alive there today, and labels earlier than 2009 may follow the old usage of the name. In Europe, BGCI records it at the botanic gardens of Bonn (Germany) and Teplice (Czech Republic) and at the Pinetum Blijdenstein (Netherlands); a 2019 paper on the glasshouses of the botanic garden of Naples shows Zamia polymorpha in its Califano glasshouses (Sibilio, 2019).

Propagation

The plant is dioecious: a male and a female plant are needed and, in cultivation, hand pollination. No germination data specific to the species have been published; the sowing failure reported in 2011 on the Fous de palmiers forum concerns seeds of uncertain origin and identity. Seeds are exempt from CITES under annotation #4, but they should come from legally sourced cultivated plants.

Pests and diseases

No pest or disease specific to the species has been documented. Cycadales.eu notes that species from climates with a dry season resist root rot better if the compost is kept fairly dry during cool periods; scale insects are, as in all cycads, the most common pest in cultivation.

Cold hardiness

There is no measurement of the cold tolerance of Zamia prasina. It is a lowland tropical species, and no reliable source indicates that it tolerates frost; Cycadales.eu advises winters of at least 5 to 10 °C (41 to 50 °F) for its group.

Mediterranean and European experience

No in-ground planting has been reported in France or Italy, and no dated frost episode concerns the species; the only French mentions, on the Fous de palmiers forum, concern seedlings grown under glass or in pots. At the Jardin zoologique tropical in La Londe-les-Maures (Var, on the French Riviera), there is no observation of this species; the only reference point in the genus, a Zamia integrifolia from Florida that survived −7 °C (19.4 °F) in February 2012 with foliage damage, cannot be transposed to a lowland tropical species never tested in cold. For readers in Mediterranean-type climates such as California or southern Australia, it should be kept frost-free.

United Kingdom, United States and Australia

No cold measurement has been published, either on forums or by botanic gardens. Trebrown, a British nursery, gives it USDA zone 9b, a commercial rating, not a measured result. In the UK it needs a heated glasshouse or conservatory.

Toxicity and precautions

No toxicity study specific to Zamia prasina has been published. The risk is, however, documented in the genus and in other cycads: Zamia contain toxic glycosides (cycasin, macrozamin), from which methylazoxymethanol is derived, and the ASPCA cites cycasin and BMAA, a neurotoxic amino acid, for Zamia furfuracea, which it lists as toxic to dogs, cats and horses, with vomiting, bloody diarrhoea and liver damage; the seeds are the most dangerous part. 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 food use is documented with certainty. Fedick and Santiago (2022), who study Maya food plants during ancient droughts, cite the “mata ratón” (Zamia polymorpha) among the few plants with edible roots that are highly drought-resistant, adding that its roots would probably need processing to remove toxins before eating: this is the authors’ hypothesis, not a documented use. These plants must never be eaten.

Frequently asked questions

Where does Zamia prasina grow?

In Belize, the Petén of Guatemala and south-eastern Mexico (Yucatán Peninsula, Chiapas, Tabasco), from savannas to tropical forest, from sea level to a few hundred metres.

How is it related to Zamia polymorpha?

It is the same species. Zamia polymorpha, described in 1998, is now a synonym of Zamia prasina, an older name (1881) that has priority.

How is it related to Zamia decumbens?

Only through a naming error. The name Zamia prasina was long given to the cycad of the Maya Mountains sinkholes, described in 2009 as Zamia decumbens, which has a decumbent above-ground stem.

Why is it so variable?

Partly because of exposure: in sun the leaves are short and narrow, in shade long and broad, sometimes on the same plant. But some forms stay constant even when moved, a sign that the variability is also genetic.

How can it be told from Zamia loddigesii?

Mainly by the female cone and the region. That of Zamia prasina is brown and ovoid, with a gradually tapering acute tip; that of Zamia loddigesii, from the Gulf of Mexico plain, is grey to cream and cylindrical, with a long constricted tip.

Is it endangered?

No, according to the IUCN, which rates it Least Concern (2022). In Mexico, however, it is subject to special protection, and like all Zamia it falls under CITES Appendix II.

Is it hardy?

Nothing suggests so. It is a lowland tropical species; in the UK and other frost-prone climates it must be grown under glass, frost-free.

Is it poisonous?

It must be assumed so. No analysis concerns the species, but the cycads studied contain serious toxins, especially in the seeds.

Further reading on Succulentes

Sources

Reference sites

Bibliography

  • Bull, W. (1881). Zamia prasina. Retail List no. 176: 20. [Original description, in a sales catalogue; text quoted by Calonje and Meerman (2009).]
  • Stevenson, D.W., Moretti, A. & Gaudio, L. (1995–1996 [1998]). A new species of Zamia (Zamiaceae) from Belize and the Yucatan Peninsula of Mexico. Delpinoa n.s. 37–38: 3–8. [Original description of Zamia polymorpha D.W.Stev., A.Moretti & Vázq.Torres; full text read.]
  • Calonje, M. & Meerman, J. (2009). What is Zamia prasina (Zamiaceae: Cycadales)? Journal of the Botanical Research Institute of Texas 3(1): 43–49. [Full text read.]
  • Calonje, M., Meerman, J., Griffith, M.P. & Hoese, G. (2009). A new species of Zamia (Zamiaceae) from the Maya Mountains of Belize. Journal of the Botanical Research Institute of Texas 3(1): 31–41. [Description of Zamia decumbens; full text read.]
  • Napolitano, A., Caputo, P. & Moretti, A. (2004 [2006]). Karyology, phytogeography, and the origin of intraspecific karyotypic variation in Zamia paucijuga and Z[amia] polymorpha (Zamiaceae). Delpinoa n.s. 46: 71–83. [Relevant passages read.]
  • Sibilio, G. (2014–2015 [2019]). The greenhouses of the Botanical Garden of Naples, Italy. Delpinoa n.s. 56–57: 69–103. [Zamia polymorpha in the Califano glasshouse.]
  • Nicolalde-Morejón, F., González-Astorga, J., Vergara-Silva, F., Stevenson, D.W., Rojas-Soto, O. & Medina-Villarreal, A. (2014). Biodiversidad de Zamiaceae en México. Revista Mexicana de Biodiversidad, suppl. 85: S114–S125. https://doi.org/10.7550/rmb.38114 [Full text read.]
  • Nicolalde-Morejón, F., Martínez-Domínguez, L., González-Aguilar, M.A. & Stevenson, D.W. (2024). Reestablishment of Zamia lawsoniana (Zamiaceae, Cycadales), an endemic species of Mexico, with first description of the ovulate strobilus. Acta Botanica Mexicana 131: e2262. https://doi.org/10.21829/abm131.2024.2262 [Text read.]
  • Lindstrom, A., Habib, S., Dong, S., Gong, Y., Liu, J., Calonje, M., Stevenson, D. & Zhang, S. (2024). Transcriptome sequencing data provide a solid base to understand the phylogenetic relationships, biogeography and reticulated evolution of the genus Zamia L. (Cycadales: Zamiaceae). Annals of Botany 134(5): 747–768. https://doi.org/10.1093/aob/mcae065 [Full text consulted on PubMed Central.]
  • Donaldson, J.S. (ed.) (2003). Cycads. Status Survey and Conservation Action Plan. IUCN/SSC Cycad Specialist Group, Gland and Cambridge. [Table 6.1: “Zamia prasina” CR and Zamia polymorpha NT; read.]
  • Fedick, S.L. & Santiago, L.S. (2022). Large variation in availability of Maya food plant sources during ancient droughts. Proceedings of the National Academy of Sciences 119(1): e2115657118. https://doi.org/10.1073/pnas.2115657118 [Relevant passage read.]
  • Limón, F., González-Astorga, J., Nicolalde-Morejón, F. & Guevara, R. (2016). Phenotypic variation of Zamia loddigesii Miq. and Z[amia] prasina W.Bull. (Zamiaceae, Cycadales): the effect of environmental heterogeneity. Plant Systematics and Evolution 302: 1395–1404. https://doi.org/10.1007/s00606-016-1338-y [Cited by Nicolalde-Morejón et al. (2024); not consulted.]
  • Bösenberg, J.D. (2022). Zamia prasina. The IUCN Red List of Threatened Species 2022: e.T66900411A66900589. https://doi.org/10.2305/IUCN.UK.2022-1.RLTS.T66900411A66900589.en [Current assessment, LC; reference given by The World List of Cycads and checked on Crossref; the Red List page could not be consulted.]
  • Stevenson, D.W. (2010). Zamia prasina. The IUCN Red List of Threatened Species 2010: e.T42116A10652583. https://doi.org/10.2305/IUCN.UK.2010-3.RLTS.T42116A10652583.en [Earlier assessment published under the name Zamia prasina, with a different taxon number from the current one; reference checked on Crossref, not consulted.]
  • Lavaud, S. (2023). Comment cultiver les Zamia en climat tempéré. Cycadales.eu. [Growing advice for groups of species; read directly.]
  • Haynes, J.L. (2022). Etymological compendium of cycad names. Phytotaxa 550(1): 1–31. https://doi.org/10.11646/phytotaxa.550.1.1 [Compendium 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. https://doi.org/10.5281/zenodo.21958524 [Reference checklist; consulted directly.]