Few cycads have generated more taxonomic confusion per square centimetre of herbarium sheet than Cycas miquelii. Described from cultivated plants of uncertain origin in 1900, later elevated to its own genus (Epicycas) on the strength of distinctive morphological features, then sunk back into synonymy with Cycas revoluta by some authorities while maintained as a valid species by others — this is a plant whose botanical identity has been debated for over a century. And yet, for the grower who encounters it, the plant itself is unmistakable: an elegant, medium-sized Cycas with long, flat leaflets, a graceful habit, and a quiet charisma that distinguishes it from the ubiquitous sago palm.
Taxonomy and nomenclature — the long debate
Cycas miquelii Warb. was described by Otto Warburg in 1900, based on plants cultivated in European botanical gardens. The epithet honours Friedrich Anton Wilhelm Miquel, the Dutch botanist who had described several Cycas species earlier in the 19th century. The critical problem with Warburg’s description is that the provenance of the cultivated plants was never precisely established — a common issue with 19th-century botanical descriptions based on garden material, where the chain of documentation between wild collection and herbarium sheet was often broken.
This uncertain provenance has been the source of the taxonomic instability. The plant has been interpreted in three fundamentally different ways by different authors:
Interpretation 1 — a synonym of Cycas revoluta: Several authorities, including the compilers of major databases such as Plants of the World Online (POWO), treat Cycas miquelii as a synonym of Cycas revoluta Thunb. Under this view, the plants Warburg described were simply cultivated sago palms that had developed atypical morphology in garden conditions.
Interpretation 2 — a distinct species: Other cycad specialists have maintained Cycas miquelii as a valid species, distinct from Cycas revoluta, based on consistent morphological differences observed in living collections. Plants consistently referred to as Cycas miquelii in specialist nurseries and botanical gardens typically display flat (not revolute) leaflet margins, longer and more graceful fronds, a more open crown architecture, and broader leaflets than Cycas revoluta. Proponents of this view argue that these differences are stable, heritable, and not simply the product of cultivation conditions.
Interpretation 3 — Epicycas miquelii: The most radical treatment was proposed by David de Laubenfels (2002), who not only maintained the species as distinct from Cycas revoluta but transferred it to an entirely new genus, Epicycas, based on differences in megasporophyll morphology, seed structure, and vegetative characters. Under de Laubenfels’ classification, Epicycas miquelii (Warb.) de Laub. was the sole member of a monotypic genus. This treatment has not been widely accepted by other cycad specialists — most consider the morphological differences insufficient to warrant generic separation from Cycas — but it underscores the genuine distinctiveness of the plant.
The practical situation in horticulture is clearer than the taxonomy: plants sold as “Cycas miquelii” in the specialist cycad trade are recognisably different from standard Cycas revoluta, and growers consistently report that these differences are maintained across generations from seed. Whether this plant deserves species rank, varietal rank, or is merely a geographic form of Cycas revoluta remains unresolved. For the purposes of this article, we treat it as a distinct entity — the plant that the horticultural world knows as Cycas miquelii — while acknowledging the ongoing taxonomic debate.
Common names: Miquel’s cycad (English). Sometimes sold under the trade name “Cycas revoluta var. miquelii” or simply as Epicycas miquelii.
Morphological description
Habit and caudex: Plants grown under the name Cycas miquelii develop an erect, columnar trunk typically reaching 1.5–4 m in height and 15–25 cm in diameter. The trunk is straight, clothed in persistent leaf bases, and similar in general form to Cycas revoluta — but tends to be somewhat more slender and to develop height more readily than the typically squat, slow-growing sago palm.
Leaves — the key distinction: Fronds are 1–2 m long — comparable to or slightly longer than typical Cycas revoluta fronds. The critical difference is in the leaflets. In Cycas revoluta, the leaflet margins are strongly revolute — rolled under toward the midrib, giving each leaflet a narrow, almost cylindrical cross-section. In Cycas miquelii, the leaflet margins are flat or only very slightly recurved, giving each leaflet a broader, more open, strap-like appearance. This single character — flat versus revolute margins — is the most reliable field distinction and the one that prompted the specific epithet revoluta for the Japanese species in the first place.
Leaflets are 15–25 cm long and 0.8–1.2 cm wide (measured flat), linear-lanceolate, with a leathery but slightly softer texture than the rigid leaflets of Cycas revoluta. The colour is glossy dark green. The overall frond is more graceful and open than the stiff, compact rosette of Cycas revoluta — the flat leaflets give the frond a lighter, more feathery quality.
New fronds emerge in a single annual flush, initially pale green to bronze. The basal leaflets are reduced to spines, as in Cycas revoluta.
Reproductive structures: Male cones are cylindrical, 20–35 cm long. Female megasporophylls are arranged in an open whorl. It is in the megasporophyll morphology that de Laubenfels found the differences he considered sufficient for generic separation — the lamina shape and tooth pattern differ from those of Cycas revoluta. Seeds are ovoid, approximately 3–4 cm long, with an orange sarcotesta.
Probable wild origin
Although the original provenance of Warburg’s plants is uncertain, the morphological profile of Cycas miquelii — flat leaflets, moderate size, arborescent habit — is consistent with populations of Cycas known from northeastern Queensland and/or Papua New Guinea. Some authors have suggested that Cycas miquelii may represent the same entity as certain populations currently included within a broadly defined Cycas media or related Australian species. Others have linked it to Melanesian populations.
Without definitive molecular data connecting the cultivated plants to specific wild populations, the geographic origin remains an educated guess. What is clear is that the plant is distinct in cultivation from both typical Cycas revoluta (from southern Japan) and typical Cycas media (from tropical Australia).
Cultivation guide
| Parameter | Recommendation |
|---|---|
| Light | Full sun to partial shade |
| Soil | Well-drained; slightly acidic to neutral |
| pH | 5.5–6.5 |
| Watering | Regular in summer; reduced in winter |
| Cold hardiness | Moderate — probably comparable to or slightly less than Cycas revoluta |
| Growth rate | Slow to moderate; slightly faster than Cycas revoluta in warm conditions |
| Container culture | Excellent |
Light
Adaptable. Full sun produces the most compact growth; partial shade is well tolerated and may produce longer, more graceful fronds. The flat leaflets display to best effect in bright, indirect light where the broader leaf surface catches the light in a way that the narrow, rolled leaflets of Cycas revoluta do not.
Soil
Standard cycad substrate: two parts quality potting compost, one part perlite or pumice, one part coarse sand. Slightly acidic to neutral pH (5.5–6.5). Good drainage is essential, as for all cycads.
Watering
Regular during the growing season, reduced in winter. The care regime is essentially identical to that of Cycas revoluta. Allow the substrate to dry partially between waterings. Less water is better during the cool season.
Cold hardiness
Limited data exists specifically for plants labelled Cycas miquelii. If the wild provenance is northeastern Queensland or Melanesia, the species would be expected to be slightly less cold-tolerant than Japanese Cycas revoluta. In practice, cultivated plants have proven hardy in the same range as Cycas revoluta in many gardens, though potentially slightly more frost-sensitive.
| USDA Zone | Expected performance (provisional) |
|---|---|
| Zone 9b+ (above −4 °C) | Should succeed outdoors year-round with good drainage |
| Zone 9a (−4 to −7 °C) | Possible with winter protection; fronds may be killed but trunk likely survives |
| Zone 8b (−7 to −10 °C) | Marginal; less likely to survive than Cycas revoluta at these temperatures |
| Zone 8a and below | Container culture with frost-free winter storage |
Container culture
Cycas miquelii is excellent in containers — manageable size, elegant frond form, and slightly faster growth than Cycas revoluta make it a rewarding pot subject. The flat leaflets create a softer, more open crown than the tightly rolled foliage of the sago palm, giving the plant a more refined appearance. Use a terracotta pot with generous drainage and the standard substrate.
How to distinguish Cycas miquelii from Cycas revoluta
This is the question that matters most to the grower. The two plants are similar in general form — both are medium-sized, arborescent cycads with a single trunk and a crown of pinnate fronds. But side by side, the differences are clear:
| Character | Cycas miquelii | Cycas revoluta |
|---|---|---|
| Leaflet margins | Flat (the key diagnostic) | Revolute — strongly rolled under toward midrib |
| Leaflet cross-section | Flat, strap-like, open | Narrow, V-shaped to cylindrical |
| Leaflet width (measured flat) | 0.8–1.2 cm | 0.5–0.8 cm (appears narrower due to rolling) |
| Leaflet texture | Leathery but somewhat flexible | Rigid, stiff |
| Frond overall impression | Lighter, more open, graceful | Stiff, compact, dense |
| Crown architecture | More open, fronds spreading wider | Tight, symmetrical rosette |
| Growth rate | Slightly faster | Very slow |
| Trunk | Tends to be more slender | Typically stockier for a given height |
The leaflet margin test is simple and conclusive: pick a leaflet and look at it in cross-section. If the margins curl under toward the midrib, forming a trough or cylinder, it is Cycas revoluta. If the margins lie flat, giving the leaflet a broad, open, strap-like profile, it is what the trade calls Cycas miquelii. This character is stable across cultivation conditions and is not affected by light, watering, or nutrition.
Propagation
Seed: Standard Cycas germination protocol. Clean the sarcotesta (toxic — wear gloves), soak 24–48 hours, germinate at 25–30 °C. Germination takes 1–3 months. Seedlings consistently produce flat leaflets from the first frond onwards — the character breeds true.
Offsets: Produced occasionally from the trunk base. Detach and root as for Cycas revoluta.
Pests and diseases
The same pest and disease profile as Cycas revoluta: Aulacaspis yasumatsui (cycad aulacaspis scale) is the most serious insect threat; root rot from overwatering is the primary disease risk. Mealybugs and spider mites are occasional problems in dry indoor conditions. The broader, flatter leaflets of Cycas miquelii may provide slightly more surface area for scale colonisation — inspect regularly.
Toxicity
All parts contain cycasin and are toxic to dogs, cats, and humans. The same level of toxicity and the same precautions as Cycas revoluta apply.
Why grow Cycas miquelii instead of (or alongside) Cycas revoluta?
For the cycad collector, the answer is simple: diversity and aesthetics. Cycas revoluta is magnificent — the most widely cultivated cycad on Earth for good reason — but its tight, symmetrical crown of rolled leaflets produces a particular look that becomes familiar. Cycas miquelii, with its flat leaflets, more open crown, and slightly more graceful frond architecture, offers a different aesthetic within the same general size range and care requirements. Placed side by side, the two plants highlight each other’s qualities: the compact precision of revoluta, the flowing elegance of miquelii.
For the taxonomically curious, it is also a living illustration of one of the most debated questions in cycad systematics — where does one species end and another begin? Growing both plants and observing their differences firsthand is worth more than reading a dozen monographs.
Authority websites
POWO — Plants of the World Online: https://powo.science.kew.org (search Cycas miquelii — currently treated as synonym of Cycas revoluta)
The Cycad Pages — Royal Botanic Gardens Sydney: https://plantnet.rbgsyd.nsw.gov.au/…
World List of Cycads: https://cycadlist.org
CITES species listing: https://speciesplus.net
Bibliography
Warburg, O. (1900). Cycadaceae. In: Engler, A. (ed.), Das Pflanzenreich IV.1: 1–92. [Original description of Cycas miquelii]
de Laubenfels, D.J. (2002). Cycadales. In: Flora Malesiana, Series I, 16: 1–32. [Erection of Epicycas]
Hill, K.D. (2004). Character evolution, species recognition and classification concepts in the Cycadaceae. In: Walters, T. & Osborne, R. (eds.), Cycad Classification: Concepts and Recommendations, pp. 23–44. CABI Publishing, Wallingford.
Whitelock, L.M. (2002). The Cycads. Timber Press, Portland. 374 pp.
Norstog, K.J. & Nicholls, T.J. (1997). The Biology of the Cycads. Cornell University Press, Ithaca. 363 pp.
Stevenson, D.W. (1992). A formal classification of the extant cycads. Brittonia 44(2): 220–223.