Ceratozamia alvarezii

Ceratozamia alvarezii is a small cycad endemic to the Sierra Madre de Chiapas, in southern Mexico, where it is known only from the municipalities of Cintalapa and Jiquipilas, in oak and pine-oak forest on limestone rocks between 900 and 1,450 m (about 2,950 to 4,750 ft). Described in 1999, this species of the genus Ceratozamia is recognised by its often branched trunk and its leaves bearing many narrow leaflets. The IUCN lists it as Endangered.

Key facts about Ceratozamia alvarezii

  • Accepted name: Ceratozamia alvarezii Pérez-Farr., Vovides & Iglesias (1999), 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: no English name; in Chiapas, “espadaña cimarrona”, “palma” and “palmita”
  • Natural range: Mexico, Chiapas (Sierra Madre de Chiapas, municipalities of Cintalapa and Jiquipilas), 900 to 1,450 m
  • IUCN status: Endangered (EN, criteria A2acd; B1ab(i,iii,v)+2ab(i,iii,v); C1), assessment published in 2022
  • CITES and other protection: CITES Appendix I (whole genus, since 1985); Annex A in the European Union
  • Documented hardiness: no data (see Cold hardiness)
  • Light and soil: in the wild, open oak or pine-oak forest on limestone rocks; no published growing advice
  • Habit and adult size: trunk 10 to 60 cm, often branched; leaves 0.36 to 1.25 m long
  • In the UK, US and Australia: no record in botanic garden collections; grown in Mexico at the Clavijero botanic garden in Xalapa
  • Toxicity: no data specific to the species; treat it as poisonous, like all cycads (see Toxicity and precautions)

How to recognise Ceratozamia alvarezii

This is a small plant with a trunk that often branches and leaves carrying many narrow leaflets, linear to lanceolate and less than 1 cm wide. The original description (Pérez-Farrera and colleagues, 1999) and the 2022 monograph give the following measurements:

  • Trunk: subglobose, becoming cylindrical with age, partly underground, 10 to 50 cm tall (up to 60 cm according to the monograph) and 9 to 30 cm across; freely branching according to the original description.
  • Leaves: 4 to 18 according to the original description (2 to 30, sometimes 40, according to the monograph), in an open crown, 54 to 109 cm long (36 to 125 cm according to the monograph), brown when they emerge; petiole 14 to 42 cm and rachis 25 to 66 cm, both armed with short, stout prickles.
  • Leaflets: 24 to 62 per leaf according to the original description, opposite to subopposite, linear-lanceolate, flat, leathery (papery according to the monograph), dark green above, 16 to 32.5 cm by 4 to 9 mm, with 5 to 9 veins; green articulation.
  • Male cones: cylindrical to conical, 11 to 31 cm by 2.5 to 4.5 cm, light green to olive green, turning creamy yellow.
  • Female cones: cylindrical to barrel-shaped, 14.5 to 19 cm long (up to 27 cm according to the monograph), olive green turning ochre brown, on a thick, upright peduncle.
  • Seeds: 1.7 to 2.5 cm (2.5 to 3 cm and spherical according to the monograph), with white flesh turning creamy yellow.

Its chromosomes have been counted: 2n = 16, as in the other Ceratozamia studied.

Hybrids

No natural or garden hybrid has been documented.

Possible confusion

Ceratozamia alvarezii mostly resembles the other narrow-leafleted species of southern Mexico:

  • Ceratozamia mirandae, also from Chiapas, is the closest according to the 2022 monograph: across populations its leaves and female cones are larger and its seeds shorter;
  • Ceratozamia matudae also has narrow leaflets, but a long, slender, decumbent female cone peduncle and a yellow leaflet articulation;
  • Ceratozamia norstogii is a much larger plant, with an upright, unbranched trunk and a spirally twisted rachis;
  • Ceratozamia sabatoi, from Querétaro and Hidalgo, has broader, longer leaflets with 9 to 14 veins;
  • Ceratozamia chimalapensis, from Oaxaca, has similar foliage but much longer female cones and oval seeds.

Taxonomy

Ceratozamia alvarezii has never changed its name. The WCVP records its publication in Novon 9, page 410, in 1999. Its authors placed it in the group of species with linear-lanceolate leaflets defined by Stevenson and colleagues (1986), with Ceratozamia matudae, Ceratozamia sabatoi and Ceratozamia kuesteriana.

Recent genetic studies place it in a different group. The study by Habib and colleagues (2023), based on 3,954 nuclear genes, puts Ceratozamia alvarezii in the norstogii subclade of the Miqueliana clade, with Ceratozamia norstogii, Ceratozamia mirandae, Ceratozamia chimalapensis and Ceratozamia vovidesii. Depending on the data set, it appears either as the sister group of all these species or as the closest relative of Ceratozamia chimalapensis. A 2024 study of cone morphology notes that the elliptic shape of the male cone scales, shared by Ceratozamia alvarezii, Ceratozamia whitelockiana, Ceratozamia mirandae and Ceratozamia chimalapensis, is a novelty specific to this clade.

Etymology and history

The epithet honours Miguel Álvarez del Toro (1917–1996), naturalist and former head of the Institute of Natural History of Chiapas, regarded as Mexico’s first conservationist (Haynes, 2022, followed by The World List of Cycads): his efforts led to the creation of the state’s first biological reserves.

The species was discovered during botanical exploration of an area that had recently become the Sierra Madre de Chiapas biosphere reserve. The type specimen, a male plant, was collected on 4 March 1996 by Miguel Angel Pérez-Farrera (number 889), in the municipality of Cintalapa, at 950 m; the holotype is kept in the CHIP herbarium, with isotypes at F, MEXU and MO. Before describing it, the authors grew plants of this species and of Ceratozamia matudae under the same conditions for two years, to check that their differences persisted. The description appeared in 1999 in the journal Novon, with a plate by Edmundo Saavedra drawn from a living plant at the Clavijero botanic garden in Xalapa.

Common names

There is no English name. From herbarium labels, the 2022 monograph records the Spanish names “espadaña cimarrona” and “palma” or “palmita” in Chiapas. “Palma” and “palmita” are also applied to other cycads and to palms.

In the wild

Ceratozamia alvarezii lives in the Sierra Madre de Chiapas, where pine-oak forest meets oak forest, on limestone rocks between 900 and 1,450 m. At 950 m, the original description describes a forest of Quercus magnifolia, Quercus elliptica and Pinus oocarpa, with an understorey of Calliandra houstoniana shrubs.

In 1999 the authors knew only two populations, in a single geographical area, and deliberately left out precise localities to discourage illegal collecting. The 2022 monograph cites collections from both municipalities, between 900 and 1,450 m.

Conservation status and regulation

Ceratozamia alvarezii is listed as Endangered (EN) on the IUCN Red List, in an assessment by J.D. Bösenberg published in 2022 (criteria A2acd; B1ab(i,iii,v)+2ab(i,iii,v); C1), according to The World List of Cycads; the IUCN data relayed by GBIF give the same category, and the reference of the assessment was checked on Crossref (30 October 2026). An earlier assessment, by Andrew Vovides, appeared in the 2010 Red List. As early as 1999, the authors of the description considered the species threatened, because the oak forests where it grows were being cleared for farming.

Like the whole genus, it has been listed in CITES Appendix I since 1 August 1985, 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); Species+ names it explicitly (checked on 30 October 2026). Seeds are not exempt. International commercial trade is limited to artificially propagated plants with the proper documents.

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 alvarezii

No growing guide has been published for Ceratozamia alvarezii. The Clavijero botanic garden in Xalapa, Veracruz, has grown plants from the type locality since the 1990s, and the authors observed that they kept in cultivation the characters seen in the wild. Its habitat, open mid-altitude forest on limestone, suggests a plant for filtered light and well-drained soil; these are deductions, not cultivation results.

Outdoor and in-ground cultivation

No outdoor planting outside Mexico has been documented. In frost-free gardens, a spot in dappled shade, in very free-draining, stony or limestone soil, would come closest to its habitat, with water during growth and a drier rest; this is inferred from the habitat, not tested.

Container cultivation

No container-growing report has been published. Its small size makes it a plausible pot plant: a deep pot for the root system, a coarse, free-draining compost and bright shade would follow its habitat. Keep it frost-free in winter until data exist.

In cultivation in the UK, US and Australia

None documented. No British, American or Australian garden declares Ceratozamia alvarezii to BGCI PlantSearch, where the only holder listed is the Francisco Javier Clavijero botanic garden of the Instituto de Ecología in Xalapa, Mexico; the online catalogue of Montgomery Botanical Center (Coral Gables, Florida) has no entry for it (both checked on 30 October 2026).

Propagation

Sowing is the only method documented for the genus. As the plant has separate male and female individuals, fertilised seed is needed. The branched trunk could in theory provide offsets, but no source describes taking them for this species.

Pests and diseases

No pest or disease has been documented for this species.

Cold hardiness

There are no data on the tolerance of Ceratozamia alvarezii to cold or drought. Its habitat, between 900 and 1,450 m in pine-oak forest in Chiapas, is cooler than the lowland tropical forests, but no minimum temperature has been published for its sites.

Mediterranean and European experience

No cultivation has been reported in France or Italy, in the ground or in a pot, and no dated frost episode concerns this species. At the Jardin zoologique tropical in La Londe-les-Maures (Var, on the French Riviera), no observation of it has been published. For readers in Mediterranean-type climates such as California or southern Australia, it should be kept frost-free until data exist.

United Kingdom, United States and Australia

No cold record and no commercial hardiness rating have been published. In the UK it would need a heated glasshouse.

Toxicity and precautions

No toxicity study concerns this species or the genus. In other cycads, the seeds and tissues contain toxic glycosides (cycasin, macrozamin), from which methylazoxymethanol is derived, a compound harmful to the liver and nervous system. The 2022 monograph nevertheless reports that the seeds of Ceratozamia alvarezii are eaten locally, without saying how they are prepared: this is in no way a guarantee that they are safe. Keep seeds and leaves out of reach of children and animals, and contact a poison centre, a doctor or a vet if any part is swallowed.

Traditional uses

According to a herbarium label cited by the 2022 monograph (the 1996 type collection), the seeds are used as food. No details are given on how they are prepared.

Frequently asked questions

Where does Ceratozamia alvarezii grow?

Only in Chiapas, Mexico, in the Sierra Madre, in the municipalities of Cintalapa and Jiquipilas, in oak and pine-oak forest on limestone between 900 and 1,450 m.

Who is it named after?

Miguel Álvarez del Toro, a Chiapas naturalist who died in 1996, regarded as Mexico’s first conservationist and the founder of the state’s first reserves.

How can I tell it from Ceratozamia mirandae?

With difficulty. The two species are very alike. Across populations, Ceratozamia alvarezii has shorter leaves, smaller female cones and longer seeds.

Is it endangered?

Yes. The IUCN has listed it as Endangered since 2022: its range is very small and its forests are being cleared for farming.

Is it frost-hardy?

Nobody knows. No trial or cultivation report has been published, and no minimum temperature is known for its habitat.

Are its seeds edible?

No, they should be treated as poisonous. Local consumption has been reported, but with no indication of preparation, and cycad seeds contain toxins that are serious for the liver and nervous system.

Further reading on Succulentes

Sources

Reference sites

Bibliography

  • Pérez-Farrera, M.A., Vovides, A.P. & Iglesias, C. (1999). A new species of Ceratozamia (Zamiaceae, Cycadales) from Chiapas, Mexico. Novon 9(3): 410–413. [Original description, habitat, chromosome count, key. 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 [Descriptions, ranges, common names; open access.]
  • Habib, S., Gong, Y., Dong, S., Lindstrom, A., Stevenson, D.W., Wu, H. & Zhang, S. (2023). Phylotranscriptomics shed light on intrageneric relationships and historical biogeography of Ceratozamia (Cycadales). Plants 12(3): 478. https://doi.org/10.3390/plants12030478 [Phylogeny; open access.]
  • Martínez-Domínguez, L., Nicolalde-Morejón, F., Vergara-Silva, F., Gernandt, D.S., Huesca-Domínguez, I. & Stevenson, D.W. (2024). Evolutionary trends of reproductive phenotype in Cycadales: an analysis of morphological evolution in Ceratozamia. Annals of Botany 134(4): 631–650. https://doi.org/10.1093/aob/mcae058 [Shape of the male cone scales.]
  • Bösenberg, J.D. (2022). Ceratozamia alvarezii. The IUCN Red List of Threatened Species 2022: e.T42122A2959813. https://doi.org/10.2305/IUCN.UK.2022-1.RLTS.T42122A2959813.en [Category and criteria as given by The World List of Cycads; category confirmed by GBIF.]
  • Haynes, J.L. (2022). Etymological compendium of cycad names. Phytotaxa 550(1): 1–31. https://doi.org/10.11646/phytotaxa.550.1.1 [Etymology, as cited 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.]