Zamia montana is a medium-sized, arborescent cycad of the family Zamiaceae, endemic to the cloud forests of Antioquia Department in the Western Cordillera of the Colombian Andes. Growing at elevations between 1,750 and 2,080 meters above sea level, it holds the distinction of being the highest-altitude Zamia — and indeed the highest-altitude Neotropical cycad — in the world. With approximately 100 adult plants known in fragmented habitat, Zamia montana is Critically Endangered and ranks among the five most threatened Zamia species in Colombia. It is virtually unknown in cultivation.
The accepted name Zamia montana A.Dietr. follows the nomenclatural authority of POWO (Plants of the World Online, Royal Botanic Gardens, Kew). The species was first described in 1882 by William Thiselton-Dyer in the Gardeners’ Chronicle, based on a plant collected by the legendary German plant hunter Gustav Wallis in the mountains of Antioquia. The specific epithet montana (Latin: “of the mountains”) directly references its highland habitat. The genus Zamia comprises over 80 recognized species distributed across the Americas.
Taxonomy and Phylogenetic Position
A Species Lost and Found
The taxonomic history of Zamia montana is marked by confusion and neglect. After its initial description in the 1880s, the species was poorly represented in herbaria and virtually absent from the living collections of botanical gardens. For over a century, it remained one of the most obscure Zamia species, known from a handful of old herbarium sheets and the original illustration by August Eichler (1881).
In 2003, Eduardo Calderón-Sáenz and Dennis Stevenson described Zamia oligodonta from Risaralda Department, another prominently-veined, high-altitude cycad from the Western Cordillera, and distinguished it from Zamia montana on the basis of stem habit and leaflet morphology. In 2009, Anders Lindstrom synonymized Zamia oligodonta under Zamia montana, arguing that the diagnostic characters represented ontogenetic (age-related) variation within a single species rather than genuine taxonomic differences.
This synonymy stood until 2015, when Calonje, Morales, López-Gallego, and Roldán published a detailed taxonomic revision based on new fieldwork in both Antioquia and Risaralda. Their study conclusively demonstrated that Zamia montana and Zamia oligodonta are distinct species with consistent morphological differences, separated by approximately 160 kilometers.
The Wallisii Subclade
Molecular phylogenetic analyses by Calonje et al. (2019) place Zamia montana within the South American clade, likely forming part of the Wallisii subclade alongside Zamia oligodonta and Zamia wallisii. These three species share a distinctive suite of characters: prominently veined, broad, coriaceous leaflets; occurrence on the Pacific slope of the Western Cordillera of Colombia; and premontane to montane forest habitats at elevations far exceeding those typical for the genus.
Natural Habitat and Distribution
Zamia montana is endemic to the department of Antioquia, where it occurs in premontane and lower montane rainforests on the Pacific (western) slope of the Western Cordillera. The altitudinal range of 1,750 to 2,080 meters makes it the highest-altitude cycad in the entire Neotropical realm.
The climate at these elevations is cloud forest: cool, wet, and consistently humid. Rainfall averages 2,400 to 2,500 mm per year with a bimodal pattern (peaks in October–November and April–May; drier months December–March and July–August). The mean annual temperature is 19.2 °C, ranging from 11.9 °C at night to 25.7 °C during the day. These are remarkably cool conditions for a cycad — nighttime temperatures routinely fall below 15 °C, and occasional dips to near 12 °C are normal.
The species grows in humid, shaded sites within the forest. It is very slow-growing and appears to have low reproductive rates. Plants are scattered in fragments of surviving forest in a landscape increasingly transformed by cattle ranching and agricultural expansion.
Morphological Description
General Habit and Stem
Zamia montana is a medium-sized cycad with an arborescent (above-ground), often decumbent (leaning or sprawling) stem reaching up to 1.5 meters in length and approximately 10 to 15 cm in diameter. The arborescent habit is one of the key characters distinguishing it from the typically subterranean-stemmed Zamia oligodonta.
Leaves and Leaflets
The crown bears a modest number of leaves — typically 3 to 6 per crown in adult plants. The petioles have sparse prickles, concentrated near the base.
The leaflets are the most distinctive feature: oblanceolate in shape, coriaceous (thick, leathery), and bearing prominently raised veins on their upper surface. This pronounced venation gives the leaflets an almost plicate (ridged) appearance, though the leaflets are not truly plicate in the same manner as the Zamia skinneri complex. The veins create a corrugated texture that is shared with Zamia oligodonta and Zamia wallisii — a signature of the Wallisii subclade.
Newly emerging leaves appear reddish or bronze, adding a brief burst of color to the understory. Eumaeus butterfly larvae have been documented feeding on the foliage in the wild.
Reproductive Structures
Zamia montana is strictly dioecious. Female cones (megastrobili) are ovoid, approximately 33 × 16 cm in juvenile stage, among the largest in the genus. Male cones (pollen strobili) are cylindrical, up to about 12 cm long. Cone production appears infrequent, consistent with the species’ slow growth rate and the shaded, cool conditions of its habitat.
Root System
Coralloid roots with nitrogen-fixing Nostoc cyanobacteria are present, as in all cycads.
Zamia montana vs. Zamia oligodonta: Resolving a Taxonomic Tangle
The 2015 revision by Calonje et al. reinstated Zamia oligodonta as distinct from Zamia montana after a period of synonymy (2009–2015). The two species are the most closely related high-altitude zamias in Colombia and share the prominently veined leaflet character, but differ in several consistent vegetative traits.
| Feature | Zamia montana | Zamia oligodonta |
|---|---|---|
| Distribution | Antioquia, W. Cordillera | Risaralda, W. Cordillera |
| Elevation | 1,750–2,080 m | 1,500–1,800 m |
| Stem | Arborescent, up to 1.5 m | Typically subterranean |
| Leaflet shape | Oblanceolate | Elliptic |
| Leaflet apex | Acute to acuminate | Acuminate to caudate |
| Leaflet teeth | Variable | Few, thick, sub-apical only |
| Leaf number per crown | 3–6 | Often more numerous |
| Known adult population | ~100 | ~1,000 |
| IUCN status | Critically Endangered (CR) | Critically Endangered (CR) |
The fastest identification cue is stem habit: an arborescent, above-ground stem indicates Zamia montana; a subterranean stem indicates Zamia oligodonta. Leaflet shape provides a secondary confirmation: oblanceolate in Zamia montana, elliptic in Zamia oligodonta.
Both species are members of the Wallisii subclade and share the prominently veined leaflet character with Zamia wallisii. However, Zamia wallisii occurs at lower elevations (600–1,300 m) and has much larger overall dimensions.
Conservation Status
Zamia montana is classified as Critically Endangered (CR) on the IUCN Red List. It is one of the five most threatened Zamia species in Colombia and is included in the national Conservation Action Plan for the Zamias of Colombia.
Threats
Extreme rarity. Approximately 100 adult plants are known across fragmented forest patches in Antioquia. This tiny population is extraordinarily vulnerable to stochastic events.
Deforestation and habitat fragmentation. The premontane and lower montane forests of the Western Cordillera in Antioquia have been heavily logged and converted to cattle pasture and agricultural land. The fragmented forest remnants where Zamia montana survives continue to shrink.
Possible extinction in the wild. Some assessments note that Zamia montana may already be extinct in the wild, as the only known population occurs in an area that has been recently logged. However, the 2015 revision confirmed the existence of surviving plants, and monitoring continues through researchers from the Universidad de Antioquia and the Sociedad Colombiana de Cícadas.
Very slow growth and low recruitment. The species grows extremely slowly and reproduces infrequently. Seedlings are rare in the wild, and the cool, shaded environment limits cone production.
Conservation Measures
Zamia montana is listed under CITES Appendix II. Ex situ material is maintained in the cycad collections of the Medellín and Bogotá Botanical Gardens. In situ monitoring is carried out by researchers from the Universidad de Antioquia and national park officials.
The most urgent conservation priorities are the formal protection of remaining habitat, the establishment of ex situ breeding populations from genetically diverse source material, and further surveys to locate any additional populations that may exist in unexplored forest fragments along the Western Cordillera.
Growing Zamia montana: Preliminary Care Guide
Zamia montana is virtually unknown in cultivation. The following guidelines are extrapolated from the species’ known habitat and should be considered highly tentative.
Light and Exposure
The species grows in the shaded understory of cloud forest. In cultivation, deep to moderate shade is essential. Direct sun should be avoided entirely.
Soil and Drainage
A rich, organic, humus-heavy, well-drained mix reflecting the loamy montane forest soils of its habitat. Combine quality potting compost, composted bark, and perlite. The soil should retain moisture without becoming waterlogged.
Temperature
This is the critical factor for Zamia montana. The species is adapted to cool equatorial montane conditions (mean annual temperature 19.2 °C, nighttime minima routinely below 15 °C, occasionally near 12 °C). While these temperatures are remarkably cool for a cycad, it is essential to understand that frost never occurs at 2,000 meters on the Colombian equatorial Andes. Despite its highland origin, Zamia montana has no evolutionary history of exposure to freezing temperatures.
For this reason, no USDA hardiness zone should be assumed, and strictly frost-free culture is recommended. A cool, humid greenhouse maintained between 12 and 22 °C year-round, never dropping below 10 °C, best approximates the species’ natural conditions. The common mistake of equating “high altitude” with “frost-hardy” does not apply to equatorial montane species.
Humidity
Extremely high humidity (80% or above) is essential, reflecting the cloud forest environment. Heated greenhouses without supplemental humidity will not sustain this species. Misting, fogging, or an enclosed terrarium-style environment may be required.
Watering
Regular, abundant watering throughout the year. There is no pronounced dry season in the species’ habitat. Allow the substrate to remain consistently moist but never waterlogged.
Toxicity
All parts of Zamia montana are presumed toxic due to the presence of cycasin and related compounds, as in all Zamia species. Keep away from pets and children.
Frequently Asked Questions
Is Zamia montana really the highest-altitude Zamia? Yes. At 1,750 to 2,080 meters, it grows at higher elevations than any other Zamia species — and any other Neotropical cycad. The closely related Zamia oligodonta (1,500–1,800 m) is the second-highest.
Is Zamia montana cold-hardy? No. Despite growing at the highest altitude of any Zamia (up to 2,080 m), the species occurs on the equatorial Andes where frost never occurs. Nighttime temperatures routinely fall below 15 °C but remain well above freezing. The common assumption that “high altitude = frost-hardy” does not apply to equatorial montane species. Strictly frost-free cultivation is recommended.
Is Zamia montana available in cultivation? It is virtually unknown in cultivation. Ex situ material exists in Colombian botanical gardens. Any plants that become available should be treated as high-priority conservation material.
What happened to the synonymy with Zamia oligodonta? Zamia oligodonta was synonymized under Zamia montana by Lindstrom in 2009, but the 2015 revision by Calonje et al. — supported by extensive fieldwork — reinstated Zamia oligodonta as a distinct species. The two differ consistently in stem habit, leaflet shape, and other characters.
Sources and Further Reading
- Calonje, M., Morales, G., López-Gallego, C. & Roldán, F. (2015). A taxonomic revision of Zamia montana and Zamia oligodonta, with notes on their conservation status. Phytotaxa, 192(4): 279–289.
- Calonje, M., Meerow, A.W., Griffith, M.P., Salas-Leiva, D., Vovides, A.P., Coiro, M. & Francisco-Ortega, J. (2019). A Time-Calibrated Species Tree Phylogeny of the New World Cycad Genus Zamia L. (Zamiaceae, Cycadales). International Journal of Plant Sciences, 180(4): 286–314.
- Lindstrom, A.J. (2009). Typification of some species names in Zamia L. (Zamiaceae), with an assessment of the status of Chigua D. Stev. Taxon, 58: 265–270.
- Sociedad Colombiana de Cícadas (SCC). Zamias de Colombia. https://www.cycadascolombia.org/
- Thiselton-Dyer, W. (1882). New Garden Plants: Zamia montana. Gardeners’ Chronicle, 17: 460.
- POWO (2026). Zamia montana A.Dietr. Plants of the World Online. Royal Botanic Gardens, Kew. https://powo.science.kew.org/
- IUCN Red List of Threatened Species. Zamia montana. https://www.iucnredlist.org/