Encephalartos


Encephalartos is a genus of cycad native to Africa. Several species of Encephalartos are commonly referred to as bread trees, bread palms or kaffir bread, since a bread-like starchy food can be prepared from the centre of the stem. The genus name is derived from Ancient Greek ἐγκέφαλος, meaning "head", and ἄρτος, meaning "bread", referring to the use of the pith to make food. They are, in evolutionary terms, some of the most primitive living gymnosperms.
All the species are endangered, some critically, due to their exploitation by collectors and traditional medicine gatherers. The whole genus is listed under CITES Appendix I which prohibits international trade in specimens of these species except for certain non-commercial motives, such as scientific research.

Description

Several of the species possess stout trunks. In E. cycadifolius, the main trunks are up to high, and several of them may be united at a base where a former main trunk once grew. The persistent, pinnate leaves are arranged in a terminal spreading crown, or ascending. The rigid leaflets are variously spiny or incised along their margins. The leaflets have a number of parallel veins and no central vein. The chromosome count is 2n=18.

Cones

Male cones are elongated, and three or four may appear at a time. Female cones are borne singly, or up to three at a time, and may weigh up to. In some species, male cones with ripe pollen emit a nauseating odour. When the pollen has been shed and the males cones decay, a strong odour of acetic acid has also been noted.

Roots

Colonies of the cyanobacterium Nostoc punctiforme occur in apparent symbiosis inside the root tissue, while the rootlets produce root tubercles at ground level which harbour a mycorrhizal fungus of uncertain function, which is however suspected to facilitate the capturing of nitrogen from the air.

Food value

Human consumption

In several species the pith of the trunk contains a copious amount of high quality starch below the crown. This was formerly cut out by native people as food. Thunberg recorded around 1772 that the Khoekhoe removed the stem's pith at the crown and buried it wrapped in animal skin for about two months, after which they recovered it for kneading into bread, whence the vernacular name "broodboom". The burial of the pith apparently facilitated its fermentation and softening, and the dough was lightly roasted over a coal fire. In 1779 Paterson likewise found that the pith of a "large palm" near King William's Town was utilised by the Africans and Hottentots as bread. The pith was removed and left till sourish, before it was kneaded into bread.

Animal food

Their large seeds consist of an often poisonous kernel covered by an edible fleshy layer. Female cones are consequently destroyed by baboons, as they relish the pith around the seeds. Vervet monkeys, rodents and birds also feed on the seeds, but due to their unpredictable toxic qualities they are not recommended for human consumption.

Insects

The early larval instars of some aposematic, day-flying looper moths are specific to cycads, and genus Encephalartos is one of their food plants. They include the leopard magpie, Millar's tiger, dimorphic tiger, spotted tigerlet, inflamed tigerlet, Staude's tigerlet and pallid grey.
In cultivation various scale insects attack the leaves of the genus. These include cycad aulacaspis scale, zamia scale and latania scale.

Taxonomy

The genus was named by German botanist Johann Georg Christian Lehmann in 1834. All cycads except Cycas had been regarded as members of the genus Zamia until then, and some botanists continued to follow this line for many years after Lehmann had separated Encephalartos as a separate genus. His concept was originally much broader than the one accepted today, including also the Australian plants we now know as Macrozamia and Lepidozamia.

Species

ImageLeavesScientific nameDistribution
Encephalartos aemulansKwaZulu-Natal Province in South Africa
Encephalartos aferEastern Cape Province of South Africa
Encephalartos altensteiniiEastern Cape and south-western KwaZulu-Natal Provinces of South Africa
Encephalartos aplanatusnorth-eastern Eswatini, South Africa
Encephalartos arenariusEastern Cape Province, South Africa
Encephalartos bartericentral Nigeria, Nigeria, Benin, Ghana, Togo
Encephalartos brevifoliolatusTransvaal, South Africa
Encephalartos bubalinusnorthern Tanzania and southern Kenya
Encephalartos cerinusBuffelsrivier Valley of KwaZulu-Natal, South Africa.
Encephalartos chimanimaniensisChimanimani Mountains of eastern Zimbabwe
Encephalartos concinnusZimbabwe
Encephalartos cupidusLimpopo Province, South Africa
Encephalartos cycadifoliusWinterberg Mountains, Eastern Cape Province, South Africa
Encephalartos delucanusRukwa Region of western Tanzania
Encephalartos dolomiticusWolkberg, southeastern Limpopo Province, South Africa
Encephalartos dyerianusnorthern Transvaal area, South Africa
Encephalartos equatorialisThurston Bay, Lake Victoria, Uganda
Encephalartos eugene-maraisiiLimpopo Province, South Africa
Encephalartos feroxsouth-eastern coast of Africa
Encephalartos friderici-guilielmiEastern Cape and KwaZulu-Natal Provinces of South Africa
Encephalartos ghellinckiiKwaZulu-Natal and northern Transkei, South Africa
Encephalartos gratusMalawi and Mozambique
Encephalartos heenaniinorth of Eswatini and Mpumalanga Province in South Africa
Encephalartos hildebrandtiiKenya and Tanzania
Encephalartos hirsutusLimpopo Province, South Africa
Encephalartos horridusEastern Cape Province, South Africa
Encephalartos humilisMpumalanga, South Africa
Encephalartos inopinusLimpopo Province, South Africa
Encephalartos ituriensisIturi forest area in the Democratic Republic of the Congo
Encephalartos kisamboKenya and Tanzania
Encephalartos laevifoliusKwaZulu-Natal, Limpopo and Mpumalanga Provinces of South Africa
Encephalartos lanatusMpumalanga Province, South Africa.
Encephalartos latifronsEastern Cape Province, South Africa
Encephalartos laurentianusnorthern Angola and southern Congo
Encephalartos lebomboensisLebombo Mountains of South Africa
Encephalartos lehmanniiEastern Cape Province, South Africa
Encephalartos longifoliusEastern Cape Province, South Africa
Encephalartos mackenzieiDidinga Hills of Namorunyang State, South Sudan
Encephalartos macrostrobilusMoyo District, northwestern Uganda
Encephalartos manikensisMozambique and Zimbabwe
Encephalartos marunguensisDemocratic Republic of the Congo and Tanzania
Encephalartos middelburgensisGauteng and Mpumalanga Provinces of South Africa
Encephalartos msinganusKwaZulu-Natal Province, South Africa
Encephalartos munchiicentral Mozambique
Encephalartos natalensisQumbu and Tabankulu areas of the northern part of the Eastern Cape, and through most of KwaZulu-Natal, South Africa
Encephalartos ngoyanusNgoye Forest, in KwaZulu-Natal, South Africa
Encephalartos nubimontanusLimpopo Province, South Africa
Encephalartos paucidentatusnear Barberton in Mpumalanga Province, and near Piggs Peak in northwestern Eswatini, in South Africa
Encephalartos poggeiDRC, Angola
Encephalartos princepsEastern Cape Province of South Africa
Encephalartos pterogonusManica Province of Mozambique
Encephalartos relictusEswatini, South Africa
Encephalartos schaijesiinear Kolwezi in Shaba Province, Democratic Republic of the Congo
Encephalartos schmitziiLuapula River watershed, in Democratic Republic of the Congo and in Zambia. A subpopulation is also found in North-Western Province, Zambia, to the east of Solwezi
Encephalartos sclavoiTanzania
Encephalartos senticosusLebombo Mountains of Mozambique, Eswatini and KwaZulu-Natal Province of South Africa.
Encephalartos septentrionalisSouth Sudan, northern Uganda, northern Democratic Republic of the Congo
Encephalartos tegulaneusEastern Province near Embu and on the Matthews Range in Rift Valley Province, Kenya
Encephalartos transvenosusLimpopo Province, South Africa
Encephalartos trispinosusEastern Cape Province, South Africa
Encephalartos turneriNampula, Mazambique.
Encephalartos umbeluziensisMozambique and Eswatini
Encephalartos villosusEast London vicinity and Eswatini, South Africa
Encephalartos whitelockiiUganda
Encephalartos woodiiKwaZulu-Natal Province, South Africa