Zamia tuerckheimii

Zamia tuerckheimii is a large cycad from Guatemala, known in the department of Alta Verapaz, where it was discovered in 1900 on damp, shaded rock faces. This species of the genus Zamia has a stem that first hangs down over the rocks, then turns upwards and reaches 1.5 to 3 m, and leaves up to 2 m long with few, broad, entire, slightly glossy leaflets. It was described in 1903 by the American botanist John Donnell Smith and named after Hans von Türckheim, who ran a coffee plantation at Cobán. The IUCN rates it Near Threatened.

Key facts about Zamia tuerckheimii

  • Accepted name: Zamia tuerckheimii Donn.Sm. (1903), accepted by The World List of Cycads (version 2026.08.15) and by GBIF; POWO could not be consulted directly
  • Former names and synonyms: none
  • Family: Zamiaceae, order Cycadales
  • Common names: none attested, in English or in Spanish
  • Natural range: Guatemala, department of Alta Verapaz (The World List of Cycads); type locality at 350 m
  • IUCN status: Near Threatened (NT), criterion B1b(v), 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
  • Documented hardiness: no data (see Cold hardiness)
  • Light and soil: in the wild, damp, shaded rock faces (original description) and forested limestone outcrops; in cultivation, light shade, a free-draining compost, constant warmth and humid air
  • Habit and adult size: upright or leaning stem 1.5 to 3 m long and about 20 cm thick, sometimes forked; up to 20 leaves, each up to 2 m long, with no more than 14 pairs of leaflets 19 to 30 cm long and 4 to 9 cm wide
  • In the UK, US and Australia: Montgomery Botanical Center, Fairchild Tropical Botanic Garden, The Huntington, Longwood Gardens and others in the United States; Royal Botanic Garden Sydney in Australia; no British record
  • Toxicity: no data specific to the species; treat it as poisonous (see Toxicity and precautions)

How to recognise Zamia tuerckheimii

This is a tree-forming Zamia, with an above-ground stem that can grow taller than a person and a crown of large leaves carrying few leaflets, broad, papery-leathery and entire, barely toothed at the tip; the petiole is unarmed or carries a few small prickles. John Donnell Smith’s original Latin description (1903) was drawn up from a collection by Hans von Türckheim and from notes sent by the collector:

  • Stem: “saxifragous”, growing on rocks, at first hanging, then ascending, 1.5 to 3 m long and 2 dm (about 20 cm) thick, sometimes forked.
  • Leaves: hairless, with 14 pairs of leaflets; petiole with scattered, tiny prickles; rachis three-angled, about 9 dm long, more than twice as long as the petiole, extended beyond the leaflets into a point 1.5 cm long; leaflets 5 to 7 cm apart.
  • Leaflets: almost opposite, oblanceolate, abruptly and shortly pointed, narrowed into a very slender base (3 mm), with an entire margin; firm and papery in texture, slightly glossy above and paler beneath; 19 to 24 cm long and 4 to 5 cm wide in the middle; more than 40 veins across the middle of the leaflet, about 8 at the base.
  • Male cone: linear-cylindrical, 14 cm long and 2.5 cm across, twice as long as its peduncle; scales covered in a greyish meal; 18 to 26 pollen sacs per scale.
  • Female cone: on a very short peduncle (2 cm), 18 cm long and 6 cm across, ending in a fine point 3 cm long, with about 9 rows of scales covered in an ash-grey felt.
  • Seeds: scarlet, obovoid, 2 cm long and 13 mm wide.

Calonje and colleagues (2009), combining the original description, the Flora of Guatemala (Standley and Steyermark, 1958), a paper by Vannini (2008) and their own measurements, give wider ranges for adult plants: an upright or leaning stem up to 3 m; up to 20 leaves, each up to 2 m long; a petiole unarmed or lightly armed; no more than 14 pairs of papery-leathery leaflets, 19 to 30 cm long and usually 4 to 9 cm wide, entire or with a few minute teeth at the tip; male cones 14 to 17 cm long and 2.5 to 4 cm across, on a peduncle up to 6.5 cm long, upright or barely leaning, with elongated triangular scales carrying 18 to 26 pollen sacs in two groups; female cones 16.3 to 22 cm long and 8.3 to 10 cm across; a single pair of leaflets on the first leaves of seedlings. They also note a marked lengthwise fold on the leaflets of this group of species, most visible near the point where they join the rachis.

Jay Vannini, a naturalist who has grown Central American cycads in the United States and Guatemala, adds field observations (2019): in the wild the trunks are often decumbent, U-shaped, S-shaped or corkscrewed, and can exceed 2.75 m (9 ft) in length at undisturbed sites; petioles range from smooth to moderately spiny depending on the locality, and leaflet shape also varies between populations. He describes a disjunct southern upland population, discovered in the early 1980s by the herpetologist Jonathan Campbell, whose plants are somewhat larger at maturity, consistently have more leaflets when older and carry two pairs of leaflets, not one, on their first seedling leaves. These are one author’s observations; no published revision has examined them.

Hybrids

No hybrid, natural or artificial, has been documented. Lindstrom and colleagues (2024) attribute some conflicts in the phylogeny of the genus to ancient or recent hybridisation; one of the reticulation events they infer concerns their clade III without Zamia meermanii, Zamia standleyi and Zamia tuerckheimii, and no hybrid involving this species is named.

Possible confusion

The closest species are Zamia decumbens, from Belize, and Zamia onan-reyesii, from Honduras: when they described Zamia decumbens, Calonje and colleagues (2009) treated Zamia tuerckheimii as its closest relative and gave a key separating the three species, whose ranges do not overlap:

  • Zamia onan-reyesii (then also called Zamia bussellii): papery leaflets, clearly toothed on the lower margin; upright or leaning stem up to 2 m; larger male cones, up to 27.5 cm, with more than 40 pollen sacs in a single group;
  • Zamia decumbens: papery-leathery, entire leaflets, but narrower (2.8 to 4.1 cm); petiole moderately to heavily prickly; creeping stem, up to 80 cm, which often rots at the base and roots again horizontally; male cones on peduncles 11 to 23 cm long that make them lean outwards;
  • Zamia tuerckheimii: papery-leathery, entire leaflets, usually 4 to 9 cm wide; petiole unarmed or lightly armed; upright or leaning stem up to 3 m; male cones on peduncles no longer than 6.5 cm.

Vannini (2019) goes further: in his view Zamia decumbens, whose known populations lie only about 48 km (30 miles) from some populations of Zamia tuerckheimii on similar limestone, might deserve review as a subspecies of it. This is one author’s opinion; no such change has been published.

Other zamias grow in Alta Verapaz. According to Calonje and colleagues (2009), material collected in the south of the department has been referred to Zamia monticola but remains poorly known; Vannini (2019) notes that these plants sometimes grow alongside Zamia tuerckheimii, which they superficially resemble, but have heavily spined petioles. When in doubt, compare habit and leaflets with the description of each species. Zamia variegata, which also occurs in Alta Verapaz, is recognised by its yellow-spotted leaflets. Nicolalde-Morejón and colleagues (2011) also group Zamia tuerckheimii with Zamia soconuscensis (Chiapas) and Zamia inermis (Veracruz), which share an above-ground stem and leaflets with entire margins, while noting that the three are not difficult to identify.

The name has also been applied to plants from other countries. According to Schutzman (1989), a plant at Fairchild Tropical Garden from Olanchito, in Honduras, whose chromosomes were studied in 1980 under the name Zamia tuerckheimii, in fact belonged to Zamia standleyi. The authors of Zamia soconuscensis, in 1988, still cited Zamia tuerckheimii “from Guatemala and Honduras”; The World List of Cycads now restricts it to Alta Verapaz. Honduran records should therefore be treated with caution. Vannini (2019) also reports that Ceratozamia hondurensis, of northern Honduras, was confused with Zamia tuerckheimii by at least two botanists and collectors, and was grown as a zamia in Australia for some time before its description in 2008; old labels may therefore hide a plant of another genus.

Taxonomy

Zamia tuerckheimii is accepted by The World List of Cycads and GBIF; POWO could not be consulted directly. It was published in January 1903 by John Donnell Smith in the Botanical Gazette (volume 35, issue 1, pages 8 to 10, plate 1), in the twenty-fourth instalment of his series “Undescribed plants from Guatemala and other Central American republics”. The type was collected by Hans von Türckheim in July 1900 “on damp, shaded rocky precipices near Cubilquitz”, in Alta Verapaz, at 350 m (number 7786 of the series of Guatemalan plants distributed by Donnell Smith); according to The World List of Cycads, the holotype is kept in Washington (US). The name has no synonyms.

In the diagnosis, Donnell Smith reports the opinion of William Thiselton-Dyer, director of the Royal Botanic Gardens, Kew, who considered the new species close to Zamia acuminata and to a “Zamia houtteana” that remained a manuscript name in the Kew herbarium; the author separates it from the former by its more numerous leaflets, from the latter by leaflets that are not sickle-shaped, and from both by more closely set veins.

Calonje and colleagues (2009) place it in a Central American group with Zamia decumbens and Zamia onan-reyesii. The transcriptome-based study of Lindstrom and colleagues (2024), which sampled a plant from Alta Verapaz, places the species in their clade III, where the species of Honduras, Guatemala and Belize form a sub-clade (III-B) of eight species, often with above-ground stems, adapted to humid cloud forest, drier deciduous forest or rocks; the text does not detail the exact position of Zamia tuerckheimii.

Etymology and history

The epithet honours Hans von Türckheim (1853–1920), a German plant collector who ran a coffee plantation at Cobán, in Guatemala, and who is credited with discovering the species (The World List of Cycads, after Haynes, 2022). The type collection is number 7786 of the series of Guatemalan plants distributed by Donnell Smith; for this species Türckheim also sent field observations (“De Tuerckheim in litt.”), such as the growth of the stem, first hanging and then ascending.

Common names

No common name is attested for Zamia tuerckheimii, in English or in Spanish, and the British nursery Trebrown knows of none.

In the wild

Zamia tuerckheimii is endemic to Guatemala, in the department of Alta Verapaz (The World List of Cycads). The original description gives its habitat: damp, shaded rock faces at 350 m near Cubilquitz, where the stem grows clinging to the rock, first hanging and then ascending. Nicolalde-Morejón and colleagues (2011) place it in tropical evergreen forest, in an area of high Zamia diversity running from Alta Verapaz and Izabal to northern Honduras, with a hot, wet climate (mean annual temperature 25 °C, or 77 °F, and 3,000 to 4,000 mm of rain a year); they note that the species is represented by only six collections in herbaria.

Vannini (2019) describes it as a large, usually rock-dwelling and often cliff-dwelling zamia of lowland wet forest in northern and central Guatemala; near the type locality he photographed a very large population along the top and face of a forested limestone drop-off, with seedlings scattered by a disintegrated cone over the thin litter on the exposed karst. Since 2007 he has found it still relatively abundant at a few sites, with limited removal of large plants for the local garden trade at easily accessible places. He considers it highly likely that the species reaches extreme eastern Chiapas, in Mexico, because some Guatemalan populations lie close to the border; The World List of Cycads does not record it there.

The published sources give neither the extent of the range nor the number of populations; pollinators and phenology are not documented. The World List of Cycads shows a series of photographs taken in Alta Verapaz in December 2014, with a deliberately imprecise map (about 11 km) to protect the populations.

Conservation status and regulation

Zamia tuerckheimii is rated Near Threatened (NT) on the IUCN Red List under criterion B1b(v), 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). The NT category covers species close to the thresholds of the threatened categories without meeting them; the criterion cited concerns a restricted range with a continuing decline in the number of mature individuals. An earlier assessment, by D.W. Stevenson, was published in 2010.

Like all Zamia except Zamia restrepoi, which is in Appendix I, Zamia tuerckheimii falls under CITES Appendix II, where the genus has been listed since 4 February 1977. The listing carries annotation #4: seeds, pollen, seedlings and tissue cultures obtained in vitro and transported in sterile containers are not covered by CITES. International trade in the plants themselves, on the other hand, requires an export permit from the country of origin. In the European Union the species is listed in Annex B of Regulation (EC) No 338/97, whose annexes are now set by Regulation (EU) 2026/1383, applicable since 29 June 2026. Species+ has no separate entry for the species, which is covered by the listing “Zamia spp.”.

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 Zamia tuerckheimii

No botanic garden has published a growing guide for this species. The French specialist nursery Cycadales.eu, which sorts the Zamia into groups by their needs (Lavaud, 2023), lists Zamia tuerckheimii as an exception among the species of Mexico and Guatemala and places it instead, with Zamia decumbens, Zamia monticola and Zamia onan-reyesii, in the group of lowland forests of Central and South America, rated “difficult”. For this group it advises:

  • a free-draining, neutral to acid compost, and neutral to acid water;
  • at night, about 22 °C (71.6 °F), with short drops to about 15 °C (59 °F) tolerated;
  • by day, 28 to 30 °C (82.4 to 86 °F), up to 34 to 35 °C (93.2 to 95 °F) for most species, with possible damage to young leaves during heat peaks;
  • high air humidity, 70 to 90 %, for best growth.

According to the same source, European climates are generally too cool and too dry for these species, even in summer, and a glasshouse, conservatory or bright, heated room is the recommended solution; keeping the compost dry in winter, which protects species from seasonally dry climates against rot, works less well for those of the humid tropics. These are recommendations from experience for a group of species, not measurements made on Zamia tuerckheimii.

Vannini (2019), who grows it in his American and Guatemalan collections, gives the only grower’s account specific to the species. He calls it well known but under-represented in cultivation, and an exceptional plant for fully tropical landscapes, very striking in mass plantings under light shade. It is not a good choice where it will get bright afternoon sun, which burns it; it grows acceptably but does not look its best in cooler tropical climates, where it is slow. In Guatemala it is widely planted in gardens of the central highlands, where it grows slowly, and he shows an established mass planting from several localities under managed tree shade in a private collection in the south-western lowlands; mature, well-grown plants can hold up to a couple of dozen healthy leaves.

Outdoor and in-ground cultivation

Outdoor planting is only realistic in fully tropical, frost-free climates. Vannini notes that most major collections of Central American cycads are in tropical and very warm subtropical areas where they can stay outdoors all year, chiefly southern Florida, Hawaii, coastal southern California and north-eastern Australia. In such climates, light shade, protection from afternoon sun and a very free-draining soil, never waterlogged, follow his advice; the damp rock faces of the habitat point the same way. This is a deduction from the habitat and from general advice, not a trial reported with this species outside the tropics.

Container cultivation

Vannini (2019) considers it suitable as a pot plant in well-lit interiors for many years, provided mealybugs are watched for. For potted Central American zamias in general he recommends a very free-draining mix, at least half pumice (preferred) or medium-grade perlite, the rest fine conifer bark and well-composted forest products, with slow-release fertiliser and dolomitic limestone as needed; mineral-rich tap water can mark the leaflets and burn the roots and leaf tips of delicate species, so reverse-osmosis or distilled water may be worth trying for plants that do not thrive. In Britain or northern Europe, this means a heated glasshouse or a warm, bright room all year.

In cultivation in the UK, US and Australia

In short: several American botanic gardens, one Australian garden and no British record.

  • United States: the online catalogue of Montgomery Botanical Center (Coral Gables, Florida) lists one accession under Zamia tuerckheimii (20160282, which by its numbering dates from 2016) and two under “Zamia aff. tuerckheimii” (20160280 and 20160281), a label for plants close to the species but not identified with it. Fairchild Tropical Botanic Garden (Miami) lists it in its online Garden Explorer (checked on 19 October 2026). BGCI also records it at The Huntington (San Marino, California), Longwood Gardens (Kennett Square, Pennsylvania), the botanical garden of the University of Hawaii at Hilo and the U.S. National Plant Germplasm System (catalogue and BGCI queried on 25 October 2026).
  • Australia: Royal Botanic Garden Sydney, which declares it to BGCI and lists it in its online Garden Explorer (checked on 19 October 2026).
  • United Kingdom: no record in BGCI or in the online catalogues of British gardens.

A BGCI declaration shows that a garden held the plant at some point, not that it is alive there today, and says nothing about whether it grows outdoors or under glass. Elsewhere, BGCI records it at the botanic garden of the Universidad del Valle de Guatemala, in Guatemala City, and at the Sarius Palmetum in Abuja (Nigeria).

Propagation

No propagation data specific to the species have been published. Like all Zamia, it has separate male and female plants and is propagated from fresh seed, after pollination; the scarlet seeds are about 2 cm long, and seedlings carry only one pair of leaflets on their first leaves (two in the southern population described by Vannini). In the wild, Vannini photographed several dozen seedlings around a fallen cone. The sometimes forked stem suggests that a branch could be removed and rooted, but no source documents it. Seeds are exempt from CITES under annotation #4, but should come from cultivated plants of legal origin.

Pests and diseases

Vannini (2019) singles out mealybugs as the pest to watch on plants grown indoors; sooty mould on the leaflets is a good sign of an infestation. For the species of the humid tropics, Cycadales.eu adds that plants grown in poor conditions, too cool or too dry, grow little, are less robust and more prone to root rot. Scale insects remain, as in all cycads, a common pest in cultivation.

Cold hardiness

There are no data on the cold tolerance of Zamia tuerckheimii, either in the wild or in cultivation. The only pointers are Cycadales.eu’s figures for the group of lowland species of the humid tropics, nights of about 22 °C (71.6 °F) with short drops to about 15 °C (59 °F) tolerated, and Vannini’s remark that it grows slowly in cooler tropical climates. Neither is a survival limit: both describe the conditions for healthy growth.

Mediterranean and European experience

No in-ground cultivation has been reported in France or Italy, and no dated frost episode concerns this species. According to Cycadales.eu, even summer nights at Montpellier, around 19 °C (66.2 °F) in the two warmest months, are a little too cool for this group. At the Jardin zoologique tropical in La Londe-les-Maures, in the Var (southern France), there is no observation of this species; the only pointer for the genus, a Zamia integrifolia from Florida that survived −7 °C (19.4 °F) in February 2012 with damage to its foliage, cannot be transferred to a species of the humid tropics that has never been tested in cold.

United Kingdom, United States and Australia

No cold record has been published. Trebrown, a British nursery, gives it USDA zone 9b: a commercial rating, not a measured result, and one that sits badly with the warm nights the nursery advice above calls for. In the UK it needs a heated glasshouse; outdoors, it belongs in fully tropical settings such as southern Florida, Hawaii or tropical north-eastern Australia, where Vannini places the main collections of Central American cycads.

Toxicity and precautions

No toxicity study specific to Zamia tuerckheimii 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 for Zamia furfuracea cycasin and BMAA, a neurotoxic amino acid, with vomiting, bloody diarrhoea and liver damage in dogs, cats and horses; 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 traditional use is documented for this species. Its only documented use is ornamental: Vannini (2019) reports that it is widely planted in gardens of the Guatemalan highlands, and that some large plants are removed from the wild for the local garden trade.

Frequently asked questions

Where does Zamia tuerckheimii come from?

From Guatemala, in the department of Alta Verapaz. The type was collected in 1900 on damp rock faces near Cubilquitz, at 350 m.

How big does it get?

It is large for a Zamia. The stem reaches 1.5 to 3 m and about 20 cm thick, and the leaves 2 m, with leaflets 19 to 30 cm long.

Does it really have iridescent blue-green leaflets?

No source says so. The original description speaks of papery-leathery leaflets, “slightly glossy above” and paler beneath.

How can I tell it from Zamia decumbens?

By the stem and the male cones. Zamia tuerckheimii has an upright or leaning stem and cones on short peduncles (no more than 6.5 cm); Zamia decumbens has a creeping stem and cones on peduncles 11 to 23 cm long. Its leaflets are also narrower.

Who was Türckheim?

Hans von Türckheim (1853–1920), a German plant collector, ran a coffee plantation at Cobán; he collected the type of the species in 1900.

Is it endangered?

Not seriously, but it is being watched. The IUCN rates it Near Threatened (2022), for a restricted range with a decline in the number of mature plants.

Can I grow it in the UK?

Only in a heated glasshouse or a warm, bright room. A specialist nursery ranks it among the difficult zamias, which need nights around 22 °C (71.6 °F) and humid air; it is grown outdoors only in fully tropical climates.

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

  • Donnell Smith, J. (1903). Undescribed plants from Guatemala and other Central American republics. XXIV. Botanical Gazette 35(1), January 1903 (Zamia tuerckheimii pages 8–10, plate 1). [Original description; 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. [Comparison with Zamia decumbens and Zamia onan-reyesii; full text read.]
  • Nicolalde-Morejón, F., González-Astorga, J., Vergara-Silva, F. & Vovides, A.P. (2011). Perspectivas sistemáticas de Zamia (Zamiaceae) en Megaméxico: de la taxonomía alfa a los códigos de barras genéticos. Revista Mexicana de Biodiversidad 82: 341–355. [Full 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 read on PubMed Central.]
  • Vannini, J. (2019). Central American and Panamanian cycads in field and greenhouse. Exotica Esoterica, 17 February 2019. [Online article by a naturalist and collector; read.]
  • Vannini, J.P. (2008). Notes on the Guatemalan cycad Zamia tuerckheimii Donn. Sm. The Cycad Newsletter 30(3): 4–7. [Cited by Calonje et al. (2009); not consulted.]
  • Standley, P.C. & Steyermark, J.A. (1958). Zamiaceae. In: Flora of Guatemala, Part I. Fieldiana: Botany 24(1): 19–20. [Cited by Calonje et al. (2009) as a source of measurements; not consulted.]
  • Schutzman, B. (1989). A new species of Zamia from Honduras. Systematic Botany 14(2): 214–219. [Olanchito plant studied under the name Zamia tuerckheimii; not reread.]
  • Bösenberg, J.D. (2022). Zamia tuerckheimii. The IUCN Red List of Threatened Species 2022: e.T42179A69845263. https://doi.org/10.2305/IUCN.UK.2022-1.RLTS.T42179A69845263.en [Current assessment, NT B1b(v); reference checked on Crossref, category confirmed by GBIF; the Red List page could not be consulted.]
  • Stevenson, D.W. (2010). Zamia tuerckheimii. The IUCN Red List of Threatened Species 2010: e.T42179A10650848. https://doi.org/10.2305/IUCN.UK.2010-3.RLTS.T42179A10650848.en [Earlier assessment; reference checked on Crossref; category not verified.]
  • 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 [Source 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.]