Zamia multidentata

Zamia multidentata is a cycad of the western Amazon, discovered on the floodplain of the Rio Moa, at the foot of the Serra do Divisor, in the Brazilian state of Acre, and since found in Peru. Described in 2023, this species of the genus Zamia stands out for its very slender aerial trunk and for leaflets whose margins bristle with 30 to 49 teeth. The IUCN has not yet assessed it; its authors proposed that it be rated Endangered.

Key facts about Zamia multidentata

• Accepted name: Zamia multidentata Calonje, Segalla & R.S.Pimenta (2023), 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: none
• Family: Zamiaceae, order Cycadales
• Common names: no name attested, in English, Portuguese or Spanish
• Natural range: Brazil (Acre, municipality of Mâncio Lima, 200 to 220 m) and Peru (Loreto, 90 to 180 m, reported in 2026); The World List of Cycads also lists Huánuco and San Martín
• IUCN status: Not Evaluated (NE); Endangered (EN) proposed by its authors in 2023
• 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 cold record; the mean minimum of the coolest month in its Brazilian range is 20.8 °C (69 °F) (see Cold hardiness)
• Light and soil: understorey of humid lowland forest; alluvial soils rich in fine sand in the type area
• Habit and adult size: aerial trunk 16 to 45 cm tall and 4 to 6.2 cm across; 8 to 14 leaves 114 to 152 cm long
• In the UK, US and Australia: no garden recorded
• Toxicity: no data specific to the species; treat it as poisonous, like all cycads (see Toxicity and precautions)

How to recognise Zamia multidentata

Four characters together identify it, according to its authors: a slender aerial trunk (6.2 cm across at most), elliptic leaflets with a long drawn-out tip, strongly toothed and marked above by a raised longitudinal crease, female cones on a long stalk, and flat female cone scales. The original description, by Rosane Segalla, Ricardo Soares Pimenta and Michael Calonje (2023), gives:

• Trunk: aerial, cylindrical, usually solitary, 16 to 45 cm tall and 4 to 6.2 cm in diameter; cataphylls falling early.
• Leaves: 8 to 14 per crown, held fairly upright and slightly spreading, 114 to 152 cm long; petiole 35 to 83 cm, with an abruptly swollen base, moderately to strongly armed with prickles 1.7 to 5 mm long; petiole and rachis covered with grey down on young leaves; rachis 43 to 78.5 cm, with prickles mostly on its lower quarter.
• Leaflets: 10 to 26, papery to thinly leathery, ovate to elliptic with a long tapering tip and a distinctly raised longitudinal crease; margin strongly toothed beyond the lower quarter, with 30 to 49 teeth; 36 to 47 veins; median leaflets 18.2 to 21.7 cm long and 4.3 to 9.3 cm wide.
• Young leaves: light green.
• Seedlings: the first leaf carries four toothed leaflets.
• Male cones: 1 to 5 per stem, conical-cylindrical, 8.2 to 8.3 cm long and 1.4 to 1.5 cm across at pollen release, with brown to grey-brown felt, on a peduncle about 9 cm long; 13 to 17 pollen sacs per scale, usually in a single group.
• Female cones: one per stem, cylindrical, 16.2 to 18 cm long and 4.7 to 5.6 cm across, dark purplish brown when emerging, turning orange-brown to mid-brown, on a peduncle 15 to 19 cm long (12 to 17.5 cm in the comparative table published by Calonje and colleagues in 2026); scales flat, not projecting.
• Seeds: ovoid-pyramidal, with a red to orange-red fleshy coat, 17.4 to 18.6 mm long and 9 to 11 mm wide.

Hybrids

No hybrid, natural or raised in cultivation, is documented.

Possible confusion

The Amazonian species that look most like it live hundreds of kilometres away, and their ranges do not overlap. The original description and the 2026 description of Zamia urarinorum give the following differences:

• Zamia hymenophyllidia (Colombian Amazonas, Peruvian Loreto): also slender-trunked, with creased leaflets, but its leaflets are membranous, with 0 to 11 teeth and 21 to 28 moderately raised veins, and its male scales carry 10 to 12 pollen sacs;
• Zamia urep (Huánuco, Peru): no aerial trunk, flat leaflets with strongly raised veins and 18 to 29 teeth, brown young leaves;
• Zamia urarinorum (permanently waterlogged forests of Loreto, described in 2026): only 2 to 6 leaves per stem, longer leaflets (up to 45.6 cm), narrowly elliptic to lanceolate, with teeth confined to the upper third or quarter; much smaller male cones (5.1 to 5.2 cm) and smaller seeds.

Taxonomy

Zamia multidentata 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, version of 4 June 2026); POWO itself could not be consulted. The species was described on 19 May 2023 in Phytotaxa (volume 598, pages 21 to 31) by Rosane Segalla (Federal Institute of Mato Grosso), Ricardo Soares Pimenta and Michael Calonje (Montgomery Botanical Center), the name being attributed to Calonje, Segalla and Pimenta. It has never had another name.

The authors point out that the Amazonian Zamia are the least understood group in the genus: those analysed so far belong to a single clade, but the relationships between its species remain unresolved. The likeness of Zamia multidentata to Zamia hymenophyllidia, suggested by their morphology, therefore does not prove a close relationship, and the species was not sampled in the transcriptome phylogeny of Lindstrom and colleagues (2024). Their work also showed that Zamia hymenophyllidia, thought to have an underground stem, sometimes forms a slender trunk: with Zamia poeppigiana and, since 2026, Zamia urarinorum, four of the eleven Amazonian Zamia now known form an aerial trunk (Calonje and colleagues, 2026).

Etymology and history

The epithet multidentata comes from the Latin multi, “many”, and dentatus, “toothed”: it refers to the numerous teeth along the margins of the leaflets (original description).

In 2015, during a survey at Mâncio Lima, Ricardo Soares Pimenta and two colleagues were shown by a local resident, Francisco Assis F. Silva, a slender-trunked Zamia that might be new. The species was found again in September 2020 in the Serra do Divisor National Park, during research on the Amazonian Zamia, and studied further in June 2021; a search of herbaria showed that it had never been collected before. The type was gathered on 26 September 2020 at Mâncio Lima, at 220 m, by Rosane Segalla and L.V. Lima (number SDMR 01); the holotype is kept at the Rio de Janeiro Botanical Garden herbarium (RB), with isotypes at UFMT, INPA and UFACPZ. Fieldwork was funded through the Plant Exploration Fund of Montgomery Botanical Center.

Common names

No common name is attested for this species, in English, Portuguese or Spanish.

In the wild

Zamia multidentata grows in the upper Juruá basin, within the south-western Amazon moist forests ecoregion. In Brazil it has only been observed in open alluvial rainforest with palms, on the soils of the Rio Moa floodplain at the foot of the Serra do Divisor, an isolated range of sharply dissected ridges that marks the border between Brazil and Peru. These soils, derived from recent sediments, are rich in fine sand and richer in nutrients than those of the range itself. The description of Zamia urarinorum (2026), however, describes it as restricted to well-drained terra firme forest, in contrast with that species of permanently flooded forest.

The climate of the Serra do Divisor is hot and very wet: 2,500 to 2,750 mm of rain a year, more than 60 mm even in the driest months (June to September), a mean annual temperature of 25 °C (77 °F), a mean daily minimum of 20.8 °C (69 °F) in the coolest month and a mean daily maximum of 28.6 °C (83 °F) in the warmest.

In the area studied the species was rare, as scattered plants in the forest understorey, on flat ground or gentle slopes, with very few seedlings and juveniles. Cones emerge from April to June; female cones become receptive and male cones shed pollen from May to June; female cones then ripen for about a year, and seeds fall from May to July of the following year. New leaves appear from October to December. The pollinator and the seed dispersers are unknown, although most South American Zamia studied are pollinated by beetles of the genus Pharaxonotha, and no damage by Eumaeus caterpillars was seen.

The original description knew only two localities in Brazil, about 30 km apart and 20 km from the Peruvian border, and noted that the species might also occur in Peru. In 2026 Calonje and colleagues reported it for Peru from two recently identified collections in Loreto, made in 2011 at 180 m (Alto Amazonas province) and in 2014 at 90 to 110 m (Requena province); an iNaturalist observation from Loreto, in June 2026, is also published on GBIF. The World List of Cycads also lists Huánuco and San Martín, without a published record for those departments.

Conservation status and regulation

Zamia multidentata has not yet been assessed by the IUCN (NE in The World List of Cycads). In 2023 its authors recommended an Endangered (EN) listing under criteria B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v); C2(i): two known localities, an extent of occurrence of 25 km², an area of occupancy of 8 km² and a decline in habitat. The type locality is protected within the national park; the other, outside the park, has been actively deforested for 40 years. Local guides reported that wild plants had been taken from the region for horticulture. This proposal predates the Peruvian records, which extend the known range considerably.

Like all Zamia except Zamia restrepoi, which is in Appendix I, Zamia multidentata is covered by the listing of the genus in CITES Appendix II, in force since 4 February 1977. Annotation #4 (the version adopted at CoP20, in force on 5 March 2026) exempts seeds, pollen, seedlings and tissue cultures obtained in vitro and transported in sterile containers, and cut flowers of artificially propagated plants; international trade in the plants themselves requires an export permit. 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+, the official CITES database, does not yet name the species, but the listing covers the whole genus (“Zamia spp.”) and therefore includes it (checked on 3 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 multidentata

No growing advice specific to Zamia multidentata has been published, and the original description cites no plant in cultivation. The collecting for horticulture reported by local guides suggests that wild plants may circulate without a known origin: be wary of any offer of wild-collected plants.

Its habitat points to an understorey plant of the tropical lowlands, warm and humid all year round, on sandy alluvial soil. The species was described after Simon Lavaud’s 2023 guide to growing Zamia in temperate climates and does not appear in it; the conditions he recommends for the Amazonian lowland species of his “difficult” group (a free-draining, neutral to acidic compost, nights at about 22 °C (72 °F), days at 28 to 30 °C (82 to 86 °F), air humidity of 70 to 90 %) are the closest published guide, but they were not written for this species.

Outdoor and in-ground cultivation

Outdoors it could only be grown in a humid tropical climate without a cool season. No outdoor planting has been documented.

Container cultivation

Elsewhere it would need a heated glasshouse with high humidity and a free-draining, sandy, slightly acidic compost, in light shade, as in its forest understorey. No grower has published a result.

In cultivation in the UK, US and Australia

In short: not recorded in any garden of these three countries.

• United Kingdom: no record in BGCI or in the online catalogues of British gardens.
• United States: no record in BGCI or in the online catalogue of Montgomery Botanical Center, although the garden funded the fieldwork that led to its description.
• Australia: no record in BGCI.

BGCI lists no garden anywhere that declares the species (queried on 25 October 2026).

Propagation

The plant is dioecious: a male and a female plant are needed to obtain seed. In the wild, female cones take about a year to ripen after pollination. No germination data have been published; the description notes only that the first seedling leaf has four toothed leaflets. Seeds are exempt from CITES under annotation #4; make sure they come from cultivated plants.

Pests and diseases

No pest or disease is documented; no damage by Eumaeus caterpillars was seen in the wild.

Cold hardiness

No cold-tolerance data exist for Zamia multidentata. In its Brazilian range the mean daily minimum of the coolest month is 20.8 °C (69 °F), and the Peruvian collections come from even lower ground: nothing suggests that it can take frost, or even a prolonged cool spell.

Mediterranean and European experience

No cultivation result has been published in France or elsewhere in Europe, either in the ground or in a pot, and no dated frost episode concerns the species. For readers in Mediterranean-type climates such as California or southern Australia, it is, on present knowledge, a plant for a heated glasshouse only.

United Kingdom, United States and Australia

No cold record or cultivation report exists from these countries.

Toxicity and precautions

No toxicity study specific to Zamia multidentata has been published. The risk is, however, well documented in cycads: Zamia contain toxic glycosides (cycasin, macrozamin), from which methylazoxymethanol is derived, a compound toxic to the liver and nervous system, and the ASPCA cites cycasin and BMAA, a neurotoxic amino acid, for Zamia furfuracea, which it lists as toxic to 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 use is documented for this species.

Frequently asked questions

Where does Zamia multidentata grow?

In the western Amazon: on the Rio Moa floodplain at the foot of the Serra do Divisor (Acre, Brazil), between 200 and 220 m, and in the lowlands of Loreto, in Peru; The World List of Cycads also lists Huánuco and San Martín.

Where does the name come from?

From the Latin multi, “many”, and dentatus, “toothed”: its leaflets carry 30 to 49 teeth, more than those of its Amazonian relatives.

Does it have a trunk?

Yes. Unlike most Amazonian Zamia, it forms an aerial trunk, but a very slender one: 16 to 45 cm tall and 4 to 6.2 cm across.

How can it be told from Zamia hymenophyllidia?

By its papery to thinly leathery leaflets, strongly toothed (30 to 49 teeth) and with many veins that are not raised, whereas those of Zamia hymenophyllidia are membranous, with few teeth and prominent veins.

How does it differ from Zamia urarinorum?

By its leaves and its habitat. Zamia multidentata has 8 to 14 leaves with leaflets up to 21.7 cm long, toothed beyond their lower quarter, and grows on drained ground; Zamia urarinorum, from waterlogged forests in Loreto, has only 2 to 6 leaves with leaflets up to 45.6 cm long, toothed only near the tip.

Is it endangered?

It has not been assessed by the IUCN. Its authors proposed in 2023 that it be rated Endangered, on the basis of two known Brazilian localities, one of them being deforested, and collecting for horticulture; the Peruvian records published since then enlarge its known range.

Is it hardy?

Almost certainly not. No cold data exist, and mean minimum temperatures in its range do not fall below about 20 °C (68 °F).

Is it poisonous?

It must be assumed so. No analysis specific to the species exists, but the cycads studied contain serious toxins, mainly in the seeds.

Further reading on Succulentes

• How to Grow Cycads from Seed: Germination, Seedling Care and Propagation Setup
• Watering Cycads: Common Mistakes and How to Avoid Them
• Is Sago Palm Toxic to Dogs, Cats & Children? What to Know

Sources

Reference sites

• The World List of Cycads (version 2026.08.15), Zamia multidentata: https://cycadlist.org/scientific_name/898 — authors, protologue, type, range (including Huánuco and San Martín), IUCN status (not evaluated). Checklist of the IUCN Cycad Specialist Group, reliable; consulted on 25 October 2026.
• Phytotaxa, Segalla et al. (2023), Zamia multidentata (Cycadales, Zamiaceae), a new arborescent species of Zamia from Acre, Brazil: https://doi.org/10.11646/phytotaxa.598.1.2 — description, type, etymology, habitat, soils, climate, phenology, conservation, comparison with Zamia hymenophyllidia and Zamia urep. Peer-reviewed original description (CC BY-NC); full text read.
• Phytotaxa, Calonje et al. (2026), Zamia urarinorum, a new cycad species from wetland forests of Loreto, Peru: https://doi.org/10.11646/phytotaxa.741.1.1 — comparison with Zamia multidentata, first Peruvian records (Loreto, 2011 and 2014), habitat on terra firme, Amazonian Zamia with trunks. Peer-reviewed article; full text read.
• World Checklist of Vascular Plants (WCVP, Royal Botanic Gardens, Kew), Zamia multidentata Calonje, Segalla & R.S.Pimenta, via GBIF: https://www.gbif.org/species/231090632 — accepted name and place of publication. Kew reference list underlying POWO; dataset of 4 June 2026, queried through the GBIF API on 25 October 2026.
• GBIF, occurrences of Zamia multidentata: https://www.gbif.org/occurrence/search?taxon_key=12192424 — type (material citation from the original description) and an iNaturalist observation from Loreto (June 2026). Primary data; queried through the GBIF API on 25 October 2026.
• PubMed Central, Lindstrom et al. (2024): https://pmc.ncbi.nlm.nih.gov/articles/PMC11560380/ — list of accepted species not sampled, including Zamia multidentata. Peer-reviewed article; full text read.
• Cycadales.eu (Simon Lavaud), Comment cultiver les Zamia en climat tempéré (6 January 2023, updated 27 May 2023, in French): https://cycadales.eu/comment-cultiver-les-zamia-en-climat-tempere/ — advice for the group of lowland Zamia, to which the species is not assigned. Specialist nursery: advice from experience for a group of species.
• Species+ (UNEP-WCMC), Zamia: https://speciesplus.net/species#/taxon_concepts/13387/legal — CITES Appendix II for the whole genus since 4 February 1977, annotation #4, Annex B in the European Union. Official CITES and EU database; consulted on 3 October 2026.
• Commission Regulation (EU) 2026/1383: https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=OJ:L_202601383 — annexes to Regulation (EC) No 338/97 in force since 29 June 2026. Official text.
• ASPCA Animal Poison Control, Cardboard Cycad: https://www.aspca.org/pet-care/aspca-poison-control/toxic-and-non-toxic-plants/cardboard-cycad — toxicity of Zamia furfuracea to dogs, cats and horses (cycasin, BMAA), cited here at genus level. Veterinary poison centre, reliable.

Bibliography

• Segalla, R., Pimenta, R.S. & Calonje, M. (2023). Zamia multidentata (Cycadales, Zamiaceae), a new arborescent species of Zamia from Acre, Brazil. Phytotaxa 598(1): 21–31. https://doi.org/10.11646/phytotaxa.598.1.2 [Original description; full text read.]
• Calonje, M., Zárate-Gómez, R., Jones, M.A., Segalla, R. et al. (2026). Zamia urarinorum (Cycadales, Zamiaceae), a new cycad species from wetland forests of Loreto, Peru. Phytotaxa 741(1): 1–17. https://doi.org/10.11646/phytotaxa.741.1.1 [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.]
• 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.]