Encephalartos cupidus - Specie described by Dyer (Blyde River Cycad)


Description
Encephalartos cupidus has well developed stems, up to 2.7m long and procumbent, but usually subterranean, suckering and 200mm to 300mm in diameter.

The leaves are up to 1m long, with mature leaves spreading and often touching the ground, or intertwined in multi-headed plants, leaf tips arching upwards. The leaves are a glaucous bluish-green to venetian blue, turning yellowish-khaki with age.

Leaflets are inserted in a distinct V-disposition on the rachis and reduced to prickles on the lower petiole. Median leaflets are up to 150mm long and 20mm broad and are strongly armed with 4-6 spines on both margins.

The male cones are green, usually single, subcylindrical, 200mm to 300mm long and 50mm in diameter with a peduncle 50mm to 100mm long. The adaxial surface of the male sporophylls bears a slight median ridge with the terminal facet of the sporophyll glabrous in the centre. Female cones are green, turning apricot at maturity or staying green in shaded plants. They are usually solitary and occur rarely in pairs. The female cones are up to 300mm long and 200mm in diameter with a peduncle up to 60mm long. The terminal facet of the sporophyll is smooth to slightly warty. Seeds are ellipsoid and the sarcotesta is yellow to apricot.


Distribution & Habitat
E. cupidus used to occur within a restricted area of the eastern Transvaal Drakensberg escarpment area, between the Blyde and Steelpoort Rivers. At present populations appear to be confined to the Blyde River Nature Reserve, with some isolated plants sporadically being found further north between the Ohrigstad and Olifants Rivers. Populations are small, up to 200 individuals in the Blyde River Nature Reserve. Plants grow in inaccessible spots on precipitous promontories and on boulder-strewn grassland or typical Bankenveld and sometimes along seepage areas bordering gallery forest as well as in dry forest. It appears as if dolomites are preferred as substrate, but plants are also found on Black Reef quartzite of the Wolkberg group.

Droughts and fires are frequent, causing a high mortality rate amongst seedlings. Recruitment is poor, although individuals from all age classes are present within the larger populations. The leaves of E. cupidus are frequently attacked by larvae of the leopard magpie moth (Zerenopsis leopardina), which is also the case with E. dyerianus and E. laevifolius. Damage by baboons does not appear to be a problem as cones appear only to be damaged severely or removed after pollination. (It appears from observations on E. cupidus, E. laevifolius and E. middelburgensis in the wild, as if the cones are unpalatable before pollination, but that this rapidly changes directly after pollination. Seed of all three species removed experimentally or by baboons within a week after artificial pollination, has shown no loss in viability.)

Cultivation & Propagation
This is a delightful, frost-hardy species for temperate to tropical areas. The soil must be well drained with ample organic material. Plants sucker from an early age and may occupy an area of 2m² at maturity. Although it will tolerate full sun, afternoon shade is preferred. It also makes an interesting container plant on a sun deck or patio. Plants are not uncommon in collections, public or private, and several plants can be seen on display at the Lowveld National Botanical Garden in Nelspruit.


Notes
Astonishment was expressed by Dr. R.A. Dyer in 1964, when first describing E. inopinus, that an undescribed species of this remarkable genus should be discovered at this comparatively late stage in the botanical exploration of southern Africa. This trend continued with the description of E. cupidus and still continues today, with several more species being discovered and needing further investigation. The first indications of this new species came to light when a leaf was sent to the then Botanical Research Institute, Pretoria, by a Mr. J.S. Oliver from a plant in cultivation in the garden of Mr. D. van Heerden of White River. The parent plant had originated some time back from a farm on the Ohrigstad River, now part of the Blyde River Nature Reserve. Further investigations into the area by members of the then B.R.I. and Nature Conservation officials, made enough material available for a full species description to be published in 1971. The meaning of the specific epithet, cupidus, refers to the passionate desire by collectors to collect the new species from the wild.

Populations of this species used to exist over a much wider area, but distribution was severely reduced by collectorsand all known wild populations are now strictly monitored for illegal removal or disturbance. Although this species is well protected within the Blyde River Nature Reserve, it unfortunately (fortunately?) occurs in very inaccessible areas which makes it difficult for cycad enthusiasts to view the plants in their natural environment. This species must be considered as endangered by conservation authorities. An intensive ex situ conservation project of this species is underway at the Lowveld National Botanical Garden. This will hopefully curb this species' rapid decline in nature, and possible extinction, by supplementing wild populations and relieving the collector pressure through artificially propagated specimens.


References & Acknowledgements

  • Encephalartos Vol 36: Focus on Encephalartos cupidus - Riekie Slabbert & Johan Hurter
  • Cycads of the World - David L Jones, 1993
  • SPECIAL THANKS TO THE CYCAD SOCIETY OF SOUTH AFRICA www.cycadsociety.org