The manikensis complex — the five green-leaved, spiny-leafleted cycads from the Zimbabwe–Mozambique borderlands described by Dyer and Verdoorn in their 1969 Kirkia paper — has four species concentrated along the eastern highlands and the Manica province: manikensis itself, chimanimaniensis, pterogonus, and munchii. The fifth species breaks the pattern. Encephalartos concinnus does not grow on the eastern escarpment. It does not grow in Mozambique. It grows in southern Zimbabwe — in the provinces of Matabeleland South, Midlands, and Masvingo — hundreds of kilometres from the nearest population of any other member of the complex, in hot, dry, steep-sided rocky valleys that share nothing with the misty Chimanimani grasslands or the humid Manica highlands except the granite substrate underfoot.
This geographic isolation is the species’ defining ecological character. Encephalartos concinnus is the outlier — the western satellite of an eastern complex, separated from its relatives by the breadth of Zimbabwe’s interior plateau. It is also the largest member of the complex: trunks reaching 3–4 m, often multiple, often lying along the ground in sprawling clumps of 3–7 stems. And it is the species for which the complex is named in miniature: concinnus means “neat” or “elegant” in Latin, referring to the compact, well-ordered arrangement of the male cone scales — a character so tidy, so visually pleasing, that Dyer and Verdoorn chose it as the species’ identity. In the genus Encephalartos where cone morphology separates species, the neat cone of concinnus is both its diagnosis and its name.
Taxonomy and nomenclature
Encephalartos concinnus R.A. Dyer & I. Verd. was first published in 1969 in Kirkia (volume 7: 147–158, page 152), in the paper that segregated the manikensis complex. The epithet concinnus derives from the Latin for “neat,” “trim,” or “well-adjusted” — referring to the orderly, compact appearance of the male cone scales. Haynes (2022) confirms this etymology. POWO gives the native range as “Zimbabwe.”
Within the complex, concinnus is diagnosed by its smaller pollen cones: 30–50 cm long and 7–10 cm in diameter — the same length range as pterogonus (30–38 cm) but narrower, and substantially shorter than the massive cones of chimanimaniensis (50–70 cm) and manikensis (25–65 cm, but typically larger in proportion to the plant). The cone scales are smooth and “neat” — lacking the curving edges of chimanimaniensis, the wing-like projections of pterogonus, and the extreme thickness of manikensis. It is a diagnosis by elegance and proportion rather than by any single dramatic character.
No synonyms exist. The species has not been subject to the parallel-naming problems that affected dolomiticus/verrucosus, nubimontanus/venetus, and dyerianus/graniticola — possibly because concinnus, in remote southern Zimbabwe, was known to fewer botanists.
Common names: Runde cycad (English, after the Runde River near one of the subpopulations).
Morphological description
Habit and caudex: Encephalartos concinnus is the largest species in the manikensis complex — and the most architecturally distinctive. The trunk reaches 3–4 m long (LLIFLE gives “up to 3–4 m”; Wikipedia gives 2.5–3 m) and 35–45 cm in diameter. Crucially, the trunks often lie along the ground rather than growing erect — a decumbent or procumbent habit that creates sprawling, multi-stemmed clumps of 3–7 trunks radiating from a common base. Africa Cycads describes it as “often producing multiple trunks and multiple branches.” This multi-stemmed, ground-hugging growth form is unique in the complex — manikensis, pterogonus, and chimanimaniensis all produce erect, single (or basally suckering) trunks — and gives concinnus a visual character quite different from its upright relatives.
LLIFLE provides the explanation for this growth habit: the species grows “on hot, dry steep-sided rocky valleys” — terrain where an erect 4 m trunk would be exposed to the full force of sun, wind, and gravity on the steep valley slopes. Lying along the ground — following the contour of the slope, spreading among the boulders — is a structural adaptation to this extreme terrain.
Leaves: The fronds are 150–200 cm long (LLIFLE; Wikipedia gives the same range), dark green, semi-glossy, with approximately 50 pairs of thin leaflets. LLIFLE adds an interesting detail: plants growing in shade develop “a distinct blue accent” — a blue-green tint on the foliage that disappears in full sun. This shade-induced blue is not the genetic blue of munchii’s ice-blue flush but an environmental response — a phenotypic plasticity that adds a further identification challenge in the field.
The leaflets bear 1–3 spines on each margin — fewer than the 3–6 of munchii, consistent with the moderate armament typical of manikensis and pterogonus. They are arranged at 45–80° on the rachis, creating a moderately keeled leaf cross-section. The petiole is short, with basal leaflets reducing to spines. LLIFLE notes: “There was some variation in the length and shape of the leaflets in the 2 existing colonies, suggesting that 2 slightly different forms of this cycad exist” — a morphological heterogeneity between populations that echoes the broader variation across the complex and raises the same taxonomic questions.
Reproductive structures: Male cones are 1–4, fusiform, green, 30–50 cm long and 7–10 cm in diameter. The cone scales are the species’ diagnostic feature: neat, compact, smooth, well-proportioned — the “elegant” arrangement that gives the species its name. The character is one of proportion and tidiness rather than any single dramatic morphological innovation (curving edges, wings, blue colour). Female cones are green, 35–45 cm long and 15–20 cm wide, ovoid. Seeds are oblong, 30–35 mm long and 8–23 mm wide, with a brown sarcotesta — a notably darker seed coat than the scarlet of manikensis or the red of chimanimaniensis.
Distribution and natural habitat
Encephalartos concinnus is endemic to southern Zimbabwe — the only member of the manikensis complex that does not extend into Mozambique or the eastern highlands. LLIFLE provides the most detailed distribution data: three subpopulations in the provinces of Matabeleland South, Midlands, and Masvingo, referred to as the Gwanda, Mberengwa, and Runde subpopulations.
Gwanda (West Nicolson): Approximately 50 mature plants. Matabeleland South province.
Mberengwa: At least 160 mature plants (only accessible areas counted — the actual number may be higher). Midlands province.
Runde: Unconfirmed reports indicate that this subpopulation may no longer exist. Masvingo province.
LLIFLE adds: “There may be other colonies close by those visited” — a hopeful note suggesting that the remote, inaccessible terrain of southern Zimbabwe may harbour undiscovered populations. The altitude range is 800–900 m.
The habitat is striking: hot, dry, steep-sided rocky valleys with few sparse trees (LLIFLE). Africa Cycads adds: “steep, rocky, misty valleys and woodlands” — the “misty” detail is significant, suggesting that despite the overall aridity of the lowveld, the valley microclimate provides some moisture through morning mist or fog, similar to the orographic mist that supports the Chimanimani species. The substrate is granite — the same acidic, sandy, well-drained rock that underlies the habitats of dyerianus, pterogonus, and munchii.
The geographic isolation of Encephalartos concinnus from the rest of the complex is remarkable. The nearest population of Encephalartos manikensis is along the Odzi and Garezi rivers in eastern Zimbabwe — several hundred kilometres to the northeast. The nearest population of any other segregate (chimanimaniensis, pterogonus, munchii) is even further, across the border in Mozambique. Encephalartos concinnus occupies the dry lowveld of southern Zimbabwe, a landscape that shares no obvious biogeographic connection with the humid eastern highlands. How did a member of an eastern-highland complex end up in the hot, dry south? The most likely explanation is a historically wider distribution — the manikensis complex may once have occupied granite outcrops across a broader swathe of Zimbabwe, with concinnus representing a relictual western/southern population that survived after the intervening populations disappeared.
Conservation — three colonies, one possibly gone
Encephalartos concinnus is assessed as Vulnerable (VU) on the IUCN Red List. The total known population is approximately 210+ mature plants across two (possibly three) subpopulations. The potential extirpation of the Runde subpopulation would reduce the species to two isolated colonies — Gwanda and Mberengwa — with a combined population of approximately 210 mature individuals.
The threats are the standard litany: illegal collection (the species is “extremely hard-to-find” in cultivation — Africa Cycads — which increases both its value and the incentive to poach it) and habitat degradation. The hot, dry valleys of southern Zimbabwe are marginal agricultural land, but they are subject to charcoal production, goat grazing, and periodic fires that can damage slow-growing cycad populations.
The species’ multi-stemmed, decumbent growth habit may provide some incidental protection: a plant with 3–7 trunks lying along a steep granite slope among boulders is physically more difficult to extract than an erect, single-trunked plant on flat ground. The logistical difficulty of removing a 4 m procumbent clump from a rocky valley is substantial. But logistical difficulty has not stopped collectors before — it merely raises the price.
Cold hardiness
The southern Zimbabwe lowveld at 800–900 m is hot in summer (often exceeding 35 °C) and mild to cool in winter. Frost is possible but infrequent and light.
Practical cold hardiness estimate: USDA Zone 9b–10a (−1 to −4 °C). The species’ hot, dry habitat origin suggests it is adapted to heat extremes rather than cold extremes. Light frost is tolerated; sustained freezing is not.
Caveat: Cold-hardiness data for Encephalartos concinnus is limited by its extreme rarity in cultivation. The two known populations are in a hot lowveld climate, and the species may have no genetic adaptation to frost. A single isolated success in a warm-temperate garden does not demonstrate reliable frost tolerance. Keep dry during cool months.
Cultivation — the slow starter with a spectacular payoff
Difficulty: 3/5. LLIFLE notes: “In its first 5 years, seedlings are not as vigorous as Encephalartos manikensis, Encephalartos munchii or Encephalartos pterogonus, however once the seedling caudex reaches 20–30 mm they grow more vigorously.” Africa Cycads confirms: the species is “extremely hard-to-find, as it does not occur in large numbers in any of its localities, but rather in small, isolated colonies. Historically, the lack of access to this plant and its seeds have made it a very rare plant in cultivation.”
The cultivation profile is therefore: slow to establish from seed (5+ years to get going), but once the caudex reaches sufficient size, the species becomes more vigorous. The ultimate reward is substantial: a multi-trunked, sprawling clump of 3–7 stems, each bearing long, dark green, semi-glossy leaves — a landscape feature that no other cycad in the complex can match for architectural impact.
Light: Full sun to partial shade. The open, steep valley habitat was exposed but with some topographic shading from valley walls. LLIFLE notes the blue-accent colour response in shade — growers who prefer the blue-green tint should provide partial shade; those who prefer the saturated dark green should grow in full sun.
Soil: Well-drained, granite-derived, acidic. The rocky valley habitat indicates a need for excellent drainage. A standard well-drained cycad mix of coarse sand, pumice, and loam works well.
Watering: Regular during the growing season. Africa Cycads: “despite the harsh environment in which it lives, does seem to like regular water and a little fertiliser.” The species is eventually drought-resistant but responds to generous watering with better growth.
Growth rate: Slow initially (seedlings), then moderate once the caudex exceeds 20–30 mm diameter. Africa Cycads describes it as deserving “to be grown more widely” — an endorsement of its garden potential despite the initial slow phase.
The multi-trunk habit: The species’ tendency to produce multiple trunks and branches — often lying along the ground — is its most distinctive ornamental character. In cultivation, this habit should be encouraged rather than trained into a single upright stem. The sprawling clump form is the species’ natural expression and its landscape strength. Allow space for horizontal spread.
Container culture: Possible when young, but the eventual multi-trunked, decumbent growth habit makes this a ground-planting species once mature. The wide-spreading clump will outgrow any reasonable container.
Propagation: Seed or suckers (the multi-stemmed habit provides natural vegetative propagation material). Seed germination follows standard protocols. Africa Cycads notes the species is “uncommon in cultivation” — any propagation effort contributes to the conservation gene pool.
Comparison within the manikensis complex
| Character | E. concinnus | E. manikensis | E. pterogonus |
|---|---|---|---|
| Distribution | Southern Zimbabwe only (most isolated) | Zimbabwe + Mozambique (widest) | Mt Mruwere, Mozambique |
| Subpopulations | Gwanda (~50), Mberengwa (~160), Runde (extinct?) | Multiple, large (esp. Mozambique) | Mt Mruwere (reintroduced ~700) |
| Trunk | 3–4 m, multi-trunked, decumbent (largest) | To 1.5–2 m, erect | To 1.5 m, erect |
| Growth habit | Sprawling clumps of 3–7 stems (unique) | Erect, suckering | Erect, suckering |
| Leaf length | 150–200 cm | 100–200 cm | 100–150 cm |
| Shade response | Blue accent in shade | No colour change | No colour change |
| Male cone size | 30–50 × 7–10 cm (smallest in complex) | 25–65 × 15–22 cm (largest) | 30–38 × 9–11 cm |
| Cone scale character | Neat, compact, smooth (diagnostic) | Thick, flat | Winged projections |
| Seed colour | Brown sarcotesta (unique in complex) | Scarlet | Red/orange |
| Seedling vigour | Slow initially (5 years to establish) | Fast from the start | Fast from the start |
| IUCN status | VU (~210 plants, 2–3 colonies) | NT (<10,000) | CR (~700, reintroduced) |
The dry valleys — an unexpected home for an eastern species
The hot, dry, steep-sided granite valleys of Matabeleland South and Masvingo are among the least expected places to find a member of the manikensis complex. The complex’s centre of gravity is the humid, montane, eastern highlands — the Chimanimani Mountains, the Mapande Range, the granite inselbergs of Manica province. These are high-rainfall, mist-prone, subtropical-to-temperate environments. The Gwanda and Mberengwa valleys are the opposite: lowveld, hot, dry, receiving perhaps 400–600 mm of rain per year, with temperatures that regularly exceed 35 °C in summer.
Yet Encephalartos concinnus thrives here — or at least persists, in its small colonies among the granite boulders. The species has adapted to the heat and drought through its multi-stemmed, ground-hugging habit (reducing wind exposure and keeping the meristems close to the thermally buffered ground surface), through its moderate cone size (smaller cones require less investment per reproductive event than the massive cones of manikensis), and possibly through its slow seedling development (a strategy that prioritises root establishment over rapid above-ground growth in a moisture-limited environment).
The presence of concinnus in southern Zimbabwe raises biogeographic questions that extend beyond the manikensis complex. Are there other granite outcrops in the interior of Zimbabwe — between the known concinnus sites and the eastern highlands — that harbour undiscovered cycad populations? LLIFLE’s note that “there may be other colonies close by those visited” suggests the answer is yes. A systematic survey of granite inselbergs across southern Zimbabwe — from Gwanda through the Masvingo lowveld to the Eastern Highlands — could fill a significant gap in our knowledge of both the species’ distribution and the broader biogeography of the manikensis complex.
Until that survey is conducted, concinnus remains the lonely western outlier — the elegant, neat-coned, multi-trunked cycad of the dry valleys, separated from its relatives by hundreds of kilometres of unsuitable habitat, counting its remaining individuals in dozens rather than thousands, and waiting for someone to look more carefully at the granite hills between here and there.
Authority websites
POWO — Plants of the World Online: https://powo.science.kew.org/…
IUCN Red List: https://www.iucnredlist.org/species/41878/121558413
World List of Cycads: https://cycadlist.org
Bibliography
Dyer, R.A. & Verdoorn, I.C. (1969). Encephalartos manikensis and its near allies. Kirkia 7(1): 147–158, p. 152. [Original description; JSTOR stable/23501059]
Whitelock, L.M. (2002). The Cycads. Timber Press, Portland. 374 pp.
Donaldson, J.S. (ed.) (2003). Cycads: Status Survey and Conservation Action Plan. IUCN/SSC Cycad Specialist Group, IUCN, Gland.
Donaldson, J.S. (2010). Encephalartos concinnus. The IUCN Red List of Threatened Species.
Haynes, J.L. (2022). Etymological compendium of cycad names. Phytotaxa 550(1): 1–31.