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Description
The stems of E. brevifoliolatus are well developed, usually unbranched but often suckering from the base to form clumps of up to 6 stems. The stem is erect but often leaning to some extent or even hanging from cliffs. Stems are up to 2.5m tall and 250mm to 300mm thick and covered by relatively small remains of leaf bases which are often charred from fires in its grassland habitat. The crown is not woolly but cataphylls (bracts) are initially covered by a thin, whitish, felt-like indumentum.
The leaves are 800mm to 900mm (1200mm?) long, rigid and straight or very slightly recurved near their apices. The petioles are unarmed, half-cylindrical and initially has a whitish felt-like indumentum but are hairless at maturity. Colour is yellowish and they are 90mm to 200mm long and 7mm to 10mm thick. The rachis is also yellowish.
The basal pinnae are very slightly reduced in size but not to prickles. The median pinnae overlap with upper margins over the lower margin of the adjoining leaflets, spaced 8mm to 10mm apart and directed towards the apex of the leaf at an angle of about 45°. Opposing leaflets are set at an angle of about 135° to each other. Colour is dark green and they are shaped very narrowly ovate and somewhat sickle-shaped, with margins entire and recurved and apices acute and pungent. The lower surface is finely ribbed with (12) 14 to 16 veins. The median leaflets are 60mm to 80mm long and 10mm to 12mm wide.
Up to 6 male cones were seen per stem. They are sessile, very narrowly egg-shaped and covered in minute and very short whitish felt-like hairs. It is about 350mm long and 60mm to 70mm in diameter in the dried state. The exposed faces of median microsporophylls (cone scales) are rhombic, about 22mm wide and 5mm high, and drawn out to a length of about 6mm to the central facet. The central facet is rhombic, smooth, 7mm to 9mm wide and 3mm to 5mm wide. The female cones are unknown.
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Distribution & Habitat
E. brevifoliolatus is known from five individuals which occur widely scattered over a few square kilometers on the Drakensberg escarpment in the Northern Province. In consideration of its vulnerable conservation status, the locality cannot be divulged in greater detail. It grows in short grassland, in very open Protea savanna, on quartzite-derived sandstone or on cliffs. Plants grow in direct sunlight at elevations of 1300m to 1500m.
Cultivation & Propagation
Very little is known about the cultivation of E. brevifoliolatus because it is so rare. None the less it is represented in at least one, possibly two , collections. It should be grown in full sun and the normal requirements for cycads should be adhered to. Since female cones are not known, this species can only be propagated by removing suckers from the base.
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Notes
Full credit for the discovery of this species is due to Mr. S.P. Fourie of the former Transvaal Chief Directorate of Nature and Environmental Conservation. He located the plants, brought them to the author's attention, collected herbarium material, and arranged for the author of the species to see the plants in nature.
Encephalartos brevifoliolatus resembles E. laevifolius by its practically identical male cones, thin but rigid and spineless petioles with whitish wool when young, and relatively narrow and entire leaflets which are finely ribbed on the lower surfaces. It differs from E. laevifolius and related species by its conspicuously wider and shorter leaflets with revolute margins and the greater number of veins per pinna, (12) 14 to 16 instead of 10 to 12 (Dyer 1965 & 1966).
Mention should be made of plants occurring on the north-eastern Drakensberg of the Northern Transvaal, and assigned to E. laevifolius. These represent a series of outlying populations of E. laevifolius, and differ from material at the type locality by their dark green instead of glaucous ("blue") foliage, as well as the densely velvety and somewhat differently shaped cones. Since Dr. Vorster discovered the first plants in 1969, they have been studied intensively, but in spite of their superficial dissimilarity to material from the type locality, the discontinuity in character states is considered insufficient to justify taxonomic separation. There is also some variation in the length/width ratio of the leaflets between populations of E. laevifolius along its geographical cline, but nowhere does it approach that of E. brevifoliolatus.
The possibility was considered that the meagre material represents a hybrid, with E. laevifolius as one of the parents, because the width/length ratio of the leaflets is larger than any ever recorded in the E. laevifolius group comprising in addition E. lanatus, E. humilis, E. friderici-guilielmi, and perhaps E. cycadifolius and E. ghellinckii. Arguments against this assumption are that there are no suitable putative parents growing nearby, that apart from the wider leaflets it shows no similarity to any species outside the E. laevifolius group, and that the reproductive cycle of the E. laevifolius group is half a year out of phase with that of the remaining species so that natural hybridizing is unlikely.
The fact that, in spite of a diligent aerial search, only five widely separated specimens could be located, coupled to the lack of evidence for the survival of female plants, leads to the conclusion that the conservation status of this species is extremely precarious. The general area where this species was found, is rich in relic endemic species of encephalartos. The fact that several of these were brought to the attention of the scientific world through the illegal activities of amateur collectors, is poor consolation for the havoc which they wreaked, to the extent that more than one species has so been reduced in numbers that it is no longer possible to study the plants in their natural habitat. E. brevifoliolatus is not present in any scientific collection but in view of the disastrous removal of an outlying population of E. laevifolius from the former Transkei to KwaZulu/Natal in the name of conservation, removal is not recommended (by the author of the species) of any material from nature, unless it proves impossible to protect the plants in situ.
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