Ceratozamia euryphyllidia

Ceratozamia euryphyllidia is a cycad of the lowland rainforests of south-eastern Mexico, found in the Uxpanapa-Chimalapas forest on the border between Veracruz and Oaxaca, between 100 and 630 m (about 330 to 2,070 ft). It is the species of the genus Ceratozamia with the broadest leaflets: each leaflet, shaped like an inverted egg, can reach 17 cm across, which gives the plant a look quite unlike other Ceratozamia. Described in 1986, it has never changed name. It survives only in small populations in a largely cleared landscape, and the IUCN Red List assesses it as Endangered.

Key facts about Ceratozamia euryphyllidia

  • Accepted name: Ceratozamia euryphyllidia Vázq.Torres, Sabato & D.W.Stev. (1986), accepted by The World List of Cycads (version 2026.08.15), by the 2022 monograph of the genus and by the World Checklist of Vascular Plants (WCVP, the database behind POWO, read via GBIF)
  • Former names and synonyms: none
  • Family: Zamiaceae, order Cycadales
  • Common names: none recorded
  • Natural range: Mexico, Uxpanapa-Chimalapas forest (southern Veracruz and eastern Oaxaca), 100 to 630 m
  • IUCN status: Endangered (EN, criteria A4cd; B1ab(iii,v)), assessment published in 2022
  • CITES and other protection: CITES Appendix I (whole genus, since 1985); Annex A in the European Union, seeds included
  • Documented hardiness: no data; a lowland rainforest species (see Cold hardiness)
  • Light and soil: in the wild, the understorey of evergreen tropical forest, on clay soils on hilltops and slopes
  • Habit and adult size: trunk 25 to 50 cm, half buried; 2 to 22 leaves, 0.95 to 3.4 m long; leaflets 20 to 36 cm by 8.5 to 17.6 cm (2022 monograph)
  • In the UK, US and Australia: Fairchild Tropical Botanic Garden (Florida), the Huntington and San Diego Botanic Garden (California); none in the UK or Australia
  • Toxicity: no data specific to the species; treat it as poisonous, like all cycads (see Toxicity and precautions)

How to recognise Ceratozamia euryphyllidia

It is recognised at a glance by its few, very broad leaflets (6 to 17 pairs per leaf), broadly obovate, thin and glossy, with an asymmetrical tip and a wavy margin towards the end. The 2022 monograph by Lilí Martínez-Domínguez and colleagues describes it as follows:

  • Trunk: 25 to 50 cm long and 8 to 15 cm in diameter, half buried, upright then lying down; persistent, triangular, reddish-brown cataphylls, woolly when they emerge.
  • Leaves: 2 to 22, ascending, 95 to 337 cm long; light green and glaucous when they emerge, with whitish-grey hairs, then hairless. The petiole, 40 to 193 cm long, green to yellowish (pink on young leaves), bears 8 to 35 thin prickles.
  • Leaflets: 6 to 17 pairs, opposite to nearly opposite, broadly obovate, membranous, green and hairless on both sides, with prominent veins; median leaflets 19.9 to 35.7 cm by 8.5 to 17.6 cm, spaced 9 to 22 cm apart.
  • Male cones: solitary, cylindrical, upright, 27 to 35 cm by 3 to 4.3 cm, yellowish green with reddish hairs when they emerge, then greenish with black hairs.
  • Female cones: solitary, upright, 15 to 20 cm by 5 to 6 cm, yellowish green with dark red hairs, then greenish brown; they end in a long point of up to 5 cm. The scales bear two straight horns 6 to 8 mm long.
  • Seeds: egg-shaped, 2.3 to 2.5 cm, with reddish-white flesh before ripening, light brown when ripe.

The original description (Stevenson, Sabato and Vázquez Torres, 1986), based on about thirty plants seen in the wild, gives a rather different picture: a short trunk (under 20 cm), fewer than 10 leaves 2 to 3.2 m long, 6 to 13 leaflets on each side, 18 to 31 cm by 9 to 16 cm, membranous to translucent, with 40 to 70 raised veins, dark copper when young and then dark green; a male cone 28 cm by 3 cm, reddish green turning light grey; and a female cone 20 cm long (with its stalk) by 5 cm, wine red when young then brown, with a mucronate tip. The main discrepancy concerns that tip: the monograph gives the female cone a long point of up to 5 cm and uses it to separate the species from Ceratozamia hondurensis, whereas the original description calls it simply mucronate.

Hybrids

No natural or garden hybrid has been documented.

Possible confusion

No other Mexican Ceratozamia has leaflets this broad. The only close look-alike is Ceratozamia hondurensis, from Honduras, which also has large obovate leaflets. According to the 2022 monograph:

  • Ceratozamia euryphyllidia: leaflet tips with a wavy margin and an asymmetrical point; female cone ending in a long point, up to 5 cm;
  • Ceratozamia hondurensis: leaflet tips with an entire margin and a symmetrical point; female cone ending in a short mucro.

The cone criterion should be used with caution, since the 1986 description already called the female cone of Ceratozamia euryphyllidia mucronate. Ceratozamia miqueliana, which the describers considered its closest relative, has leaflets of a similar shape but smaller, papery and not wavy. In collections, the geographical origin of the plant is usually enough to decide; a plant of unknown origin can only be identified reliably with its cones.

Taxonomy

Ceratozamia euryphyllidia has never changed name and its status is not disputed. It is accepted by The World List of Cycads, by the 2022 monograph and by the WCVP, which records its publication in Brittonia 38, page 17. It was described in 1986 in Brittonia (volume 38, pages 17 to 26); the article is signed by D.W. Stevenson, S. Sabato and M. Vázquez Torres, but the name is attributed to Vázquez Torres, Sabato and Stevenson.

The describers regarded Ceratozamia miqueliana as its closest relative. They placed it in a group of species with broad, thin, asymmetrical leaflets, buried stems and small cones (with Ceratozamia hildae, Ceratozamia latifolia and Ceratozamia miqueliana), in which leaflet size and thinness increase with the humidity of the habitat: Ceratozamia euryphyllidia, from the wettest forest, has the largest leaflets in the genus. They added that the plant keeps its characters in cultivation as well as in the wild, unlike some other species whose leaflets change with growing conditions.

The 2022 monograph compares it mainly with Ceratozamia hondurensis, the only other species with broadly obovate leaflets, without specifying their relationship within the genus.

Etymology and history

The epithet euryphyllidia comes from the Greek eurys, “broad”, and phyllon, “leaf”, and refers to the exceptionally broad leaflets of the species (Haynes, 2022, as quoted by The World List of Cycads; 2022 monograph). The authors of the original description thank the botanist Rupert Barneby for suggesting this Greek-derived epithet.

The type is a female plant collected by Mario Vázquez Torres (number 2842) on 22 June 1984 according to the original description and The World List of Cycads (21 June according to the monograph), in evergreen tropical forest at 120 m, in the municipality of Minatitlán (Veracruz) according to the monograph. The holotype is kept at the New York Botanical Garden (NY), with duplicates at CHAPA, NY and XALU. The describers deliberately left out the locality to protect the plants from commercial collectors. The earliest known collections date from 1982 and 1983, in the municipalities of Jesús Carranza and Minatitlán.

Common names

No common name is known. The 2022 monograph records none in Mexico, and no English name specific to the species is documented.

In the wild

Ceratozamia euryphyllidia is endemic to the Uxpanapa-Chimalapas forest, a large block of tropical rainforest straddling southern Veracruz and eastern Oaxaca. According to the 2022 monograph, it grows in evergreen tropical forest, on clay soils on the tops and sides of hills, between 100 and 630 m. Herbarium specimens come from the municipalities of Minatitlán, Jesús Carranza, Uxpanapa and Hidalgotitlán (Veracruz) and Santa María Chimalapa (Oaxaca). The WCVP places it in the Mexican Gulf and south-western Mexico regions.

The labels of the early collections describe tall evergreen forest with Guarea, Pouteria, Guatteria and Cyclanthaceae, on hills with deep, shaded, moist soils rich in organic matter; another comes from forest mixed with dense thickets of the bamboo Olmeca recta, another from gentle hills with clay soil and a few limestone outcrops, between 120 and 150 m. Uxpanapa is also home to Ceratozamia dominguezii and Zamia purpurea.

The monograph authors counted two populations, each with 20 to 60 adult plants. The Veracruz population is reproducing (coning plants, juveniles and seedlings), but it is small and surrounded by land transformed by human activity. In 1986, the describers had seen only about thirty plants in the wild and feared that commercial collecting would drive the species to extinction. No study of its pollination or phenology has been published.

Conservation status and regulation

Ceratozamia euryphyllidia is assessed as Endangered (EN, criteria A4cd; B1ab(iii,v)) on the IUCN Red List, in the assessment by J.D. Bösenberg published in 2022: criterion A reflects a past and continuing decline of the populations, criterion B a very small, fragmented and shrinking range. The category is given by The World List of Cycads and confirmed by the Red List data relayed by GBIF (checked on 30 October 2026). The 2022 monograph, written before that assessment was published, still cited the earlier, more severe category, Critically Endangered (criterion B2ab), and recommended keeping it.

Like the whole genus, it has been listed in CITES Appendix I since 1 August 1985 (the genus had been in Appendix II since 1977), and in Annex A of Regulation (EC) No 338/97 in the European Union (annexes now set by Regulation (EU) 2026/1383, applicable since 29 June 2026). International commercial trade in wild-collected plants is prohibited; only artificially propagated plants, with the required documents, may be traded. Species+ lists it by name; seeds are covered (checked on 30 October 2026).

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

Growing Ceratozamia euryphyllidia

No botanic garden or specialist society has published growing advice for this species, and no dated growing report is documented. On a French forum, growers described it in 2013 as having one of the finest foliages in the genus, but also as almost impossible to find in Europe and very expensive. Without data, the only guide is its habitat: the understorey of a warm, humid lowland rainforest on clay soil. That suggests light shade, warm and humid air all year round, and a substrate that holds a little moisture without ever staying waterlogged. Its large, thin leaflets suggest that it dislikes direct sun and dry air, but no observation confirms this.

Outdoor and in-ground cultivation

No outdoor planting has been documented. It could only be considered in frost-free tropical gardens, in shade and shelter from wind; the gardens that declare it in Florida and California do not say whether their plants grow outdoors or under glass.

Container cultivation

Elsewhere it is a plant for a warm glasshouse or conservatory: a large pot of free-draining but moisture-retentive compost, bright shade, high humidity and a minimum temperature well above freezing. Its leaves, which can exceed 3 m in the wild, need room.

In cultivation in the UK, US and Australia

In the United States, Fairchild Tropical Botanic Garden (Coral Gables, Florida) lists the species in its online Garden Explorer (updated 16 October 2026) and declares it to BGCI PlantSearch, as do the Huntington (San Marino, California) and San Diego Botanic Garden (Encinitas, California). Outside these countries, BGCI lists the Clavijero botanic garden in Xalapa and the Jardín Etnobotánico de Oaxaca, both in Mexico. No garden in the UK or Australia declares it, and Montgomery Botanical Center does not list it in its catalogue (BGCI and Montgomery checked on 30 October 2026). A BGCI listing shows that a garden has declared the species at some point, not that a living plant is there today.

Propagation

No data specific to the species. Like all Ceratozamia, it has separate male and female plants; it is propagated from fresh seed, which in cultivation requires hand pollination between a male and a female plant. Clean the seeds wearing gloves and sow them warm, in a free-draining mix.

Pests and diseases

No pest or disease specific to the species has been documented. The usual risks for cycads in cultivation are root and trunk rot in cold, wet soil, and scale insects.

Cold hardiness

No cold-tolerance data exist for Ceratozamia euryphyllidia. It is a lowland rainforest species, living between 100 and 630 m: nothing suggests that it can take frost.

Mediterranean and European experience

No growing result has been published in France or Italy, in the ground or in a pot, and no dated frost episode concerns it. At the Jardin zoologique tropical in La Londe-les-Maures (Var, on the French Riviera), no observation of it has been published. In Europe it remains a plant for a heated glasshouse or conservatory.

United Kingdom, United States and Australia

No cold record and no commercial hardiness rating have been published. The cold-hardiness reference points available for the genus concern mountain species such as Ceratozamia hildae or Ceratozamia kuesteriana, and cannot be transferred to this lowland species.

Toxicity and precautions

No toxicity data exist for the species or the genus. The risk is documented in other cycads: their seeds and leaves contain toxic glycosides (cycasin, macrozamin), from which methylazoxymethanol is derived, a compound harmful to the liver and nervous system. Dogs, livestock and people can be seriously poisoned. Treat the plant as poisonous, keep seeds and leaves out of reach of children and animals, wear gloves to clean the seeds, and if any part is swallowed, call a poison centre, a doctor or a vet straight away.

Traditional uses

No use is known; the 2022 monograph records none.

Frequently asked questions

Why are its leaflets so broad?

Because that is the defining feature of the species, and the origin of its name: euryphyllidia means “broad-leaved”. Its leaflets can exceed 17 cm across, a record among the Ceratozamia of Mexico; the describers linked their size to the very wet forest it lives in.

How does it differ from Ceratozamia hondurensis?

By the edge and tip of the leaflets, then by the cones. In Ceratozamia euryphyllidia, the end of the leaflet is wavy and its point asymmetrical; in Ceratozamia hondurensis, the margin is entire and the point symmetrical. The two species also live far apart, in Mexico and Honduras.

Is it cold-hardy?

No, as far as anyone knows. No cold data exist, and the species lives in lowland rainforest between 100 and 630 m. Grow it frost-free, in a warm glasshouse or indoors.

Where does it grow in the wild?

Only in the Uxpanapa-Chimalapas forest, between southern Veracruz and eastern Oaxaca, in Mexico, in the understorey of humid tropical forest on clay soils.

Is it endangered?

Yes. It has been assessed as Endangered by the IUCN since 2022; the two populations counted for the 2022 monograph held only 20 to 60 adults each, in a heavily deforested region.

Can it be bought?

Only with documents. Like the whole genus, it is in CITES Appendix I and Annex A of the EU regulation, seeds included; only cultivated plants with proof of origin may be sold, and it remains rare in the trade.

Further reading on Succulentes

Sources

Reference sites

Bibliography

  • Stevenson, D.W., Sabato, S. & Vázquez-Torres, M. (1986). A new species of Ceratozamia (Zamiaceae) from Veracruz, Mexico with comments on species relationships, habitats, and vegetative morphology in Ceratozamia. Brittonia 38(1): 17–26. https://doi.org/10.2307/2807413 [Original description: Latin diagnosis, description, type and paratypes, relationship with Ceratozamia miqueliana, etymology, species groups. Primary source.]
  • Martínez-Domínguez, L., Nicolalde-Morejón, F., Vergara-Silva, F. & Stevenson, D.W. (2022). Monograph of Ceratozamia (Zamiaceae, Cycadales): an endangered genus. PhytoKeys 208: 1–102. https://doi.org/10.3897/phytokeys.208.80382 [Description, range, populations, proposed status; open access.]
  • Bösenberg, J.D. (2022). Ceratozamia euryphyllidia. The IUCN Red List of Threatened Species 2022: e.T42099A69867130. https://doi.org/10.2305/IUCN.UK.2022-1.RLTS.T42099A69867130.en [Current assessment, Endangered; category given by The World List of Cycads and GBIF, reference found on Crossref.]
  • Haynes, J.L. (2022). Etymological compendium of cycad names. Phytotaxa 550(1): 1–31. https://doi.org/10.11646/phytotaxa.550.1.1 [Source of the etymology given by The World List of Cycads.]
  • 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.]