Zamia wallisii is a medium-sized cycad of the family Zamiaceae, endemic to the humid montane forests of Antioquia Department on the Pacific slope of Colombia’s Western Cordillera. The species carries a singular botanical distinction: its individual leaflets — reaching up to 60 cm in length and approximately 28 cm in width — rank among the largest of any living gymnosperm, broader than those of any conifer, Ginkgo, Welwitschia, or other cycad. First described in 1875, then effectively missing from science for nearly a century before its rediscovery in the 1980s, Zamia wallisii stands today as one of the most enigmatic and severely threatened cycads of South America. Fewer than 1,000 mature individuals are estimated across its fragmented range, making this species both a flagship for Colombian conservation and a sobering measure of how rapidly Andean forests can erode the heritage they shelter.
The genus Zamia comprises more than eighty recognized species distributed across the Americas, from the southeastern United States to Bolivia. Zamia wallisii represents one of its most spectacular and least accessible members, confined to a few remote forest fragments in the northern Andes.
How to Recognize Zamia wallisii ?
Habit and Stem
Zamia wallisii develops a subterranean rhizome that rarely emerges above the soil surface — a feature it shares with the two other members of the Wallisii subclade, Zamia oligodonta and Zamia montana. This buried growth habit shields the apical meristem from physical injury, drought stress, and the occasional fire that may sweep through pre-montane forest edges. The trade-off is that the plant’s entire aerial signature consists of its remarkable foliage and the occasional reproductive cone.
Leaves and Leaflets
The crown typically supports only two leaves, occasionally three — an unusually parsimonious display for a Zamia species and one of several singularities of the species. Each leaf may reach approximately 3 m in length, sometimes more in vigorous specimens, with a petiole armed with a few medium-sized prickles.
The leaflets define the species. Each leaf carries a maximum of approximately 11 leaflets in total — far fewer than is typical for the genus — but this restraint is more than offset by their proportions. According to the taxonomic comparisons published by Calonje, López-Gallego and Castro (2018) in their description of Zamia paucifoliolata, Zamia wallisii possesses the broadest leaflets of any species in the genus. Individual leaflets reach approximately 60 cm long and 28 cm wide, broadly elliptic, thick, leathery, and traversed by the strongly raised parallel veins that define the Wallisii subclade. The lamina presents a deeply sculptural surface, with prominent grooves between the veins producing a markedly plicate (corrugated) texture. New flushes emerge in pale reddish tones, providing a brief but striking seasonal accent.
In terms of raw foliole dimensions, Zamia imperialis of Panama holds the genus record for length (middle leaflets reaching 75 cm long), but its blades are considerably narrower (around 21 cm wide). Zamia wallisii therefore takes the title for width and total leaf-blade area per leaflet, while Zamia imperialis retains the record for length. No other living gymnosperm — coniferous, ginkgoalean, gnetalean, or cycadalean — approaches these dimensions.
Cones
The species is strictly dioecious. Female cones (megastrobili) are bulky and grayish-green; male cones (microstrobili) are slimmer and pale beige to cream. Coning has been documented in April, June and October across natural populations. Pollination is entomophilous, in keeping with the universal pollination syndrome of the genus: the Sociedad Colombiana de Cícadas reports the involvement of beetles in the genus Pharaxonotha (Erotylidae), observed on the male strobili of Zamia wallisii in field studies.
Female cones are ovoid in shape and bear few but proportionally large seeds — a character that is shared with Zamia oligodonta and Zamia montana and is considered diagnostic for the Wallisii subclade.
Roots
As in all cycads, Zamia wallisii develops coralloid roots in its superficial layer, harboring symbiotic cyanobacteria of the genus Nostoc capable of biological nitrogen fixation. This adaptation likely contributes to its ability to thrive on relatively young or thin forest soils.
Hybrids
No spontaneous or cultivated hybrids of Zamia wallisii have been documented in the published literature. The species’ extreme rarity in the wild, its relative geographical isolation from other Colombian cycads, and its near-total absence from international horticultural circulation make hybrid formation highly unlikely. The two closest relatives within the Wallisii subclade — Zamia montana and Zamia oligodonta — are themselves rare in cultivation and occupy different elevational bands in nature, further reducing any opportunity for natural crossing. To date, no cultivar nor any hybrid population has been formally reported for the species.
Possible Confusion
Vegetatively, Zamia wallisii may be confused with the two other members of the Wallisii subclade — Zamia oligodonta and Zamia montana — which share its subterranean stem, leathery prominently-veined leaflets, and restricted distribution along the Colombian Western Cordillera. The discriminating characters below allow reliable identification.
Against Zamia oligodonta, Zamia wallisii differs by a markedly lower leaflet number (up to approximately 11 leaflets versus up to 26 in Zamia oligodonta), substantially larger leaflet dimensions (up to 60 × 28 cm versus narrower, more elliptic blades), a broadly rounded to acuminate leaflet apex, and the absence of the conspicuous thick sub-apical teeth that are characteristic of Zamia oligodonta. Zamia oligodonta additionally occupies higher elevations (1,500–1,800 m) in the department of Risaralda, well outside the known range of Zamia wallisii.
Against Zamia montana, Zamia wallisii likewise displays broader and less numerous leaflets, and occupies a lower elevational band (600–1,300 m versus 1,750–2,080 m for Zamia montana).
A theoretical confusion with Zamia imperialis, occasionally raised because of the giant leaflets of both species, has no field relevance: the two species are not sympatric (Zamia imperialis is Panamanian, Zamia wallisii is Colombian), and the leaflets of Zamia imperialis are markedly longer but narrower, producing an overall silhouette quite distinct from that of Zamia wallisii.
The following comparison summarizes the key differences between Zamia wallisii and Zamia oligodonta:
| Feature | Zamia wallisii | Zamia oligodonta |
|---|---|---|
| Distribution | Antioquia (Frontino, Urrao) | Risaralda |
| Elevation | ~600–1,300 m | 1,500–1,800 m |
| Stem | Subterranean | Subterranean |
| Number of leaves | 2 (rarely 3) | Up to 3 |
| Leaf length | ~3 m (occasionally more) | Up to 2.7 m |
| Number of leaflets | Up to ~11 (total) | Up to 26 |
| Leaflet dimensions | Up to 60 × 28 cm | Narrower, elliptic |
| Leaflet apex | Broadly rounded to acuminate | Acuminate to caudate |
| Sub-apical teeth | Absent or inconspicuous | Thick, prominent, few |
| New leaf color | Pale reddish | Pale reddish |
| Known population | <1,000 adults | ~500–1,000 adults |
| IUCN status (2022) | Critically Endangered (CR) | Critically Endangered (CR) |
Taxonomy
The accepted name Zamia wallisii H.J.Veitch follows the nomenclatural authority of POWO (Plants of the World Online, Royal Botanic Gardens, Kew). The species was first introduced into the formal botanical literature by Harry James Veitch in the Gardeners’ Chronicle (new series, vol. 3, p. 795) in 1875, based on material cultivated by the London nursery of James Veitch & Sons. A more developed diagnosis was published the same year by Alexander Braun in the Monatsberichte der Königlich Preussischen Akademie der Wissenschaften zu Berlin (p. 376), which historically led much of the horticultural and taxonomic literature to attribute the species to A.Braun. That attribution remains current on IPNI and — more significantly — in the World List of Cycads (Calonje, Stevenson & Osborne 2026, Montgomery Botanical Center), which serves as the reference taxonomic resource for the order Cycadales. POWO has nevertheless retained the earlier Veitch publication under the principle of priority. The present account follows POWO; readers accustomed to the World List of Cycads convention will find the same taxon under the name Zamia wallisii A.Braun.
The specific epithet honors Gustav Wallis (1830–1878), a German plant collector who explored Colombia, Ecuador and Brazil on behalf of several European nurseries, most notably Veitch. Wallis is credited with the original collection of Zamia wallisii in the mountains of Antioquia during one of his Colombian expeditions, where he also gathered the original material of Zamia montana.
The single recognized homotypic synonym is Aulacophyllum wallisii (H.J.Veitch) Regel, published by Eduard August von Regel in Gartenflora (vol. 25, p. 143) in 1876. This combination reflects the now-abandoned segregation of plicate-leaved Zamia species into the separate genus Aulacophyllum Regel.
A lectotype was designated by Lindstrom (2009) from material preserved at the Stockholm Herbarium (S), a typification step that stabilized the name despite the loss of the original Wallis and Kalbreyer collections.
The Wallisii Subclade
The molecular phylogenetic analyses of Calonje and collaborators (2019), based on broad taxonomic sampling across Zamia, placed Zamia wallisii and Zamia oligodonta in a well-supported Wallisii subclade nested within the South America West of the Andes clade. The same authors hypothesized, on morphological and biogeographical grounds, that Zamia montana — not sampled in their study — also belonged to this subclade. The phylotranscriptomic study of Lindstrom and collaborators (2024), which for the first time included Zamia montana in a large-scale molecular survey of the genus, confirmed the phylogenetic coherence of the three Andean species. All three share a recurring suite of converging characters: subterranean to semi-arborescent stems, broad coriaceous leaflets with prominent venation, ovoid female cones bearing few but large seeds, and a distribution restricted to the Pacific slope of the Colombian Western Cordillera.
In the Wild
Zamia wallisii is endemic to Antioquia Department in Colombia, occurring exclusively on the western slopes of the Western Cordillera. Documented localities include the municipalities of Frontino and Urrao and the Las Orquídeas National Natural Park. The species occupies elevations broadly between 600 and 1,300 m according to field-based sources, while the Catálogo de Plantas y Líquenes de Colombia retains a narrower range of 900–1,000 m for the populations it documents.
Habitat consists of pre-montane to lower montane rainforest characterized by high atmospheric humidity, frequent cloud cover, abundant annual precipitation, and moderate temperatures lacking any pronounced dry season. The plants grow in the forest understory on well-drained, humus-rich slopes, in light filtered through the canopy.
The IUCN Red List assessment published by López-Gallego in 2022 classifies Zamia wallisii as Critically Endangered (CR), criterion B1ab(iii,v). The National Red List of Colombia (2022) likewise applies the CR category. The species is listed in CITES Appendix II.
The Sociedad Colombiana de Cícadas (SCC) estimates fewer than 1,000 adult individuals across the species’ known range. Earlier assessments, made shortly after the rediscovery of the 1980s, reported a single population of fewer than 50 individuals; subsequent fieldwork has documented additional subpopulations, but the species remains severely fragmented. Direct threats include deforestation for cattle ranching and agricultural expansion, ongoing pressure on the remaining forest fragments, very small effective population sizes, and intrinsically slow growth coupled with low reproductive rates — all factors that constrain recovery.
The discovery and rediscovery history merits a closer look. After the initial collection by Gustav Wallis in the early 1870s, the German plant hunter Wilhelm Kalbreyer (also known as Guillermo Kalbreyer in Colombia) re-collected the species in 1888 near Frontino, again on behalf of Veitch. Both collection series were subsequently lost — the Wallis material very likely destroyed during the bombing of the Berlin herbarium in 1943 — and no holotype had been formally designated. For nearly a century Zamia wallisii survived only as a name in older literature, its very existence treated with skepticism by some specialists. Living populations were not relocated until the 1980s, when surveys led by Ian Sutherland Turner identified surviving plants in the vicinity of Frontino, confirming that this extraordinary cycad still persisted in the wild. The typification of the name was later stabilized by the lectotype designation of Lindstrom (2009).
Ex situ conservation measures have been undertaken in several Colombian botanical institutions, with cultivated material maintained in the botanical gardens of Medellín, Bogotá and Floridablanca. Zamia wallisii is included in the National Conservation Action Plan for Colombian Zamia species, and researchers from CES University and Universidad de Antioquia monitor populations within a Regional Integrated Management District (Distrito Regional de Manejo Integrado) under the authority of CORANTIOQUIA, the regional environmental agency. The SCC also highlights the species’ “very good ornamental potential, little explored in Colombia,” reinforcing the case for legally propagated material as both a conservation asset and a flagship horticultural taxon.
Outdoor / In-Ground Cultivation
Outdoor in-ground cultivation of Zamia wallisii is realistic only in genuinely tropical or equatorial climates without any frost incidence, such as parts of lowland Central and South America, Hawaii, the Caribbean, or equivalent tropical zones in southeast Asia and Oceania. The species is excluded from open-ground culture throughout temperate, Mediterranean, oceanic and continental climates of Europe and North America.
Where the climate allows, plants should be sited in dappled to partial shade beneath a high overhead canopy, replicating the filtered light conditions of the lower montane understory. The SCC notes that the species “establishes and grows well both in open and in semi-shaded sites,” which suggests greater light tolerance than would be expected from its native sheltered habitat — however, prolonged direct sun should be avoided, especially on newly emerging foliage, which remains tender for several weeks after unfurling.
Soils must be deep, rich in organic matter, freely draining, and capable of retaining steady moisture without ever becoming waterlogged. A planting hole prepared with quality compost, composted bark and a substantial mineral component will mimic the structure of cool montane forest soils. Atmospheric humidity remains a limiting factor: the species thrives in cloud-forest conditions where relative humidity routinely exceeds 75 %.
Container Cultivation
Container cultivation under glass is the realistic option for most growers outside the tropical belt and remains, in practice, almost the only way Zamia wallisii will be encountered in private collections.
A deep pot is recommended to accommodate the subterranean rhizome, with a substrate combining high-quality potting compost, composted bark, and a mineral drainage fraction (pumice, fine pozzolana, perlite or coarse grit) accounting for roughly 30 % of total volume. Drainage rate must be rapid, while structural moisture retention should remain consistent. Watering is generous during the active growth period, with a brief surface dry-down accepted between applications; reduce frequency in cooler periods but never allow the substrate to dry completely.
Atmospheric humidity should be maintained as close as possible to 75 % or above. Day-night temperature should remain within roughly 15–25 °C, with a strict winter minimum well above 10 °C. Zamia wallisii is a strictly frost-free species and tolerates none of the cool dormancy that some North American or East Mexican Zamia species accept.
The combination of vast, ribbed leaflets, pale reddish new growth and a compact subterranean habit makes Zamia wallisii — in principle — among the most spectacular cycads imaginable for a tropical conservatory display. The SCC explicitly notes its “very good ornamental potential, little explored in Colombia.” In practice, container culture in Europe remains largely theoretical given the rarity of legally available material.
Propagation
Propagation of Zamia wallisii is by seed only, as is true for nearly all cycads. The strict dioecy of the genus combined with the very small wild populations means that fertile seed production depends on the simultaneous presence of mature male and female plants in cultivation, ideally hand-pollinated to maximize fecundity in ex situ collections. The Colombian botanical gardens involved in Zamia conservation programs have built up sufficient material to undertake such crosses, but the species remains essentially absent from European seed circulation.
Seeds are few but large, and should be sown fresh after careful removal of the fleshy sarcotesta. Sowing media should be free-draining, kept consistently warm (25–28 °C) and humid. As with most Zamia species, germination can extend over several months and proves irregular. Seedlings grow slowly, and the diagnostic adult foliage — broad, plicate, prominently veined — does not appear until plants are several years old.
No vegetative method, such as trunk cuttings or division, is applicable to Zamia wallisii: the subterranean rhizome does not produce lateral suckers suitable for separation under standard horticultural protocols. In vitro embryo culture protocols have been explored on other Zamia species, but no published work documents their application to Zamia wallisii.
Diseases and Pests
In the absence of published European cultivation reports, the phytosanitary risks anticipated for Zamia wallisii are those common to Zamia species maintained in warm-temperate glasshouses.
Mealybugs (Pseudococcidae) and armored scale insects (Diaspididae) — most notably Aulacaspis yasumatsui, the Cycad Aulacaspis Scale — are the principal arthropod threats to cultivated cycads worldwide. Aulacaspis yasumatsui has spread globally since the late 1990s and warrants careful inspection of any new material entering a collection. Established infestations are typically managed with horticultural oil applications combined with systemic insecticides, with strict quarantine of incoming plants the most effective preventive measure.
Spider mites can appear under conditions of low humidity, underscoring the importance of maintaining the high atmospheric humidity recommended for this species.
Root rots caused by oomycetes, particularly Phytophthora species, remain the leading cause of cultivation losses in cycads. These pathogens are almost invariably the consequence of compact substrates or excessive watering during cool periods. Prevention rests on the discipline of free drainage and restraint in watering whenever active growth is paused.
Hardiness
Zamia wallisii is a strictly tropical species with no demonstrated cold tolerance. It corresponds to USDA zone 11 and beyond, and in-ground cultivation is realistic only under truly equatorial or tropical humid climates without any cold season.
Across Mediterranean, oceanic and continental European climates, cultivation is necessarily restricted to a heated glasshouse or conservatory with a winter minimum maintained well above 10 °C. Prolonged exposure to temperatures below 8 °C results in serious foliar damage, and proximity to freezing is typically lethal.
This intolerance contrasts with the cold tolerance demonstrated by certain Caribbean or subtropical Zamia species such as Zamia integrifolia and Zamia pygmaea, both of which withstand brief sub-zero episodes in cultivation. Zamia wallisii, evolved in equatorial cloud forest, has had no historical exposure to cold and possesses no acquired tolerance.
Traditional Uses
No traditional uses are documented for Zamia wallisii, in keeping with its extreme rarity and very restricted range. The vernacular name “chigua,” sometimes encountered for the species, is in fact a generic term applied in Colombia to several Zamia species whose starchy seeds were historically processed by Indigenous communities after laborious detoxification, primarily as a subsistence food during periods of scarcity. This tradition is documented chiefly for Zamia muricata and Zamia melanorrhachis; it has never been formally recorded for Zamia wallisii, whose populations have presumably remained too small and too geographically restricted to constitute an exploitable resource at the human scale.
As is true for all cycads, every part of the plant must be regarded as toxic owing to the presence of cycasin and related compounds (methylazoxymethanol, BMAA — β-methylamino-L-alanine), which are hepatotoxic and neurotoxic. No domestic or culinary use of the species should be considered. Cultivated specimens should be kept out of reach of pets and young children.
The only current legitimate use is ornamental, in scientific botanical collections or conservation institutions, and exclusively from material produced under legal ex situ propagation (Colombian botanical gardens within the framework of the National Action Plan).
Frequently Asked Questions
Does Zamia wallisii really have the largest leaflets of any gymnosperm? Yes, in terms of individual blade area. Its leaflets reach approximately 60 cm long and 28 cm wide. Zamia imperialis of Panama holds the genus record for leaflet length (up to 75 cm), but with narrower blades (around 21 cm), so the total area per leaflet remains greater in Zamia wallisii. No other extant gymnosperm — conifer, Ginkgo, Welwitschia, or other cycad — produces leaflets approaching these dimensions.
Was Zamia wallisii really lost for 100 years? Effectively yes. After the second collection of 1888 by Wilhelm (Guillermo) Kalbreyer, no living plants of Zamia wallisii were documented for almost a century. Both historical collection series were lost, and no holotype had been formally designated. Surveys led by Ian Sutherland Turner in the 1980s rediscovered living populations near Frontino, Antioquia. The taxonomic status of the name was subsequently stabilized by Lindstrom (2009), who designated a lectotype from surviving material at the Stockholm Herbarium.
Is Zamia wallisii available in cultivation? Almost never. The species is listed in CITES Appendix II and remains concentrated in a few Colombian botanical gardens (Medellín, Bogotá, Floridablanca). Any commercial offer should be subjected to rigorous verification of legal-origin documentation. At present, responsible distribution flows exclusively through scientific and conservation networks.
How does Zamia wallisii relate to Zamia montana and Zamia oligodonta? All three belong to the Wallisii subclade — a group of prominently-veined zamias endemic to the Pacific slope of the Colombian Western Cordillera. Zamia wallisii occupies the lowest elevations (600–1,300 m), Zamia oligodonta the intermediate band (1,500–1,800 m), and Zamia montana the highest (1,750–2,080 m). The three species share subterranean to semi-arborescent stems, broad coriaceous leaflets, ovoid female cones with few large seeds, and a strictly Colombian distribution.
Why such enormous leaflets? The evolution of broad, leathery leaflets in Zamia wallisii most plausibly represents adaptation to the shaded understory of humid montane forest, where the photosynthetic efficiency of individual plants depends on maximizing light-capture surface in a chronically light-limited environment. The same evolutionary trajectory is detectable in several other tropical understory plant groups, but rarely expressed to the degree observed in this species.
Reference Sites
Plants of the World Online (POWO), Royal Botanic Gardens, Kew. Zamia wallisii: https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:77176960-1
World List of Cycads (Calonje, Stevenson & Osborne), Montgomery Botanical Center. Zamia wallisii: https://cycadlist.org/scientific_name/8
International Plant Names Index (IPNI). Zamia wallisii: https://www.ipni.org/n/77176960-1
IUCN Red List of Threatened Species. Zamia wallisii (2022, CR): https://www.iucnredlist.org/species/42121/69834104
Sociedad Colombiana de Cícadas (SCC). Zamias de Colombia: https://www.cycadascolombia.org/
Catálogo de Plantas y Líquenes de Colombia, Universidad Nacional de Colombia: http://catalogoplantasdecolombia.unal.edu.co
The Cycad Pages, Royal Botanic Gardens Sydney: https://plantnet.rbgsyd.nsw.gov.au/PlantNet/cycad/
CITES, Appendices: https://cites.org/eng/app/appendices.php
Bibliography
Braun, A. (1875). Die Frage nach der Gymnospermie der Cycadeen erläutert durch die Stellung dieser Familie im Stufengang des Gewächsreichs. Monatsberichte der Königlich Preussischen Akademie der Wissenschaften zu Berlin, May 1875: 289–377, Zamia wallisii p. 376. [Extended diagnosis published the same year as Veitch’s prior publication; Zamia wallisii A.Braun remains the author attribution retained by the World List of Cycads.]
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. [Calibrated molecular phylogeny — defines the Wallisii subclade and hypothesizes Zamia montana membership.]
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. [Taxonomic revision and diagnostic keys for the closely related Wallisii subclade species.]
Calonje, M., López-Gallego, C. & Castro, J. (2018). Zamia paucifoliolata, a new species of Zamia (Zamiaceae, Cycadales) from Valle del Cauca, Colombia. Phytotaxa, 385(2): 85–93. [Description of a closely related species; provides the primary statement that Zamia wallisii bears the broadest leaflets in the genus and a maximum of 11 leaflets per leaf.]
Calonje, M., Stevenson, D.W. & Osborne, R. (2026). The World List of Cycads (Version 2026.03.10). Coral Gables, FL: Montgomery Botanical Center. https://www.cycadlist.org/ [Reference taxonomic resource for cycads; retains Zamia wallisii A.Braun.]
Glos, R.A.E., Salzman, S., Calonje, M., Vovides, A.P., Coiro, M., Gandolfo, M.A. & Specht, C.D. (2022). Leaflet Anatomical Diversity in Zamia (Cycadales: Zamiaceae) Shows Little Correlation with Phylogeny and Climate. The Botanical Review, 88: 437–452. [Comparative leaflet anatomy across the genus, including Zamia wallisii.]
Haynes, J.L. (2022). Etymological compendium of cycad names. Phytotaxa, 550(1): 1–31. [Etymology of the specific epithet and biographical note on Gustav Wallis.]
Lindstrom, A.J. (2009). Typification of some species names in Zamia L. (Zamiaceae), with an assessment of the status of Chigua D.W.Stev. Taxon, 58(1): 265–270. [Lectotype designation for Zamia wallisii from material conserved at the Stockholm Herbarium (S).]
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. [First phylotranscriptomic study of the genus, including Zamia montana for the first time in a large-scale molecular analysis.]
López-Gallego, C. (2022). Zamia wallisii. The IUCN Red List of Threatened Species 2022: e.T42121A69834104. https://doi.org/10.2305/IUCN.UK.2022-1.RLTS.T42121A69834104.en [Current IUCN assessment, Critically Endangered B1ab(iii,v).]
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Veitch, H.J. (1875). Zamia wallisii. Gardeners’ Chronicle, new series, 3: 795. [Original publication of the name, retained by POWO as the valid protologue.]