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| Photo Ken Hill
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| The Cycad Pages
| | Encephalartos dolomiticus
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- Encephalartos dolomiticus Lavranos & D.L. Goode, Bull. Jard. Bot. Belg. 58: 219-224 (1988). H—NH
- TYPE: Republic of South Africa, Transvaal, Drakensberg Mountains, N of Penge and S of The Downs, alt ca 1200, 1975, A. Prozeski s.n. (holo NH iso MO).
Encephalartos verrucosus Robbertse, Vorster & S. van der Westhuizen, S. African J. Bot. 54: 487-490, figs 1-3 (1988). H—PRE
- TYPE: Republic of South Africa, North-eastern Transvaal, Farm "Ostend", north of Penge, Matthyson & Nitsche 9a (holo PRE).
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| Photo Ken Hill
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Etymology:
Dolomite, a type of magnesium-rich limestone, with the Latin suffix
iticus, --
Literature:
Illustrations:
Vernacular:
Historical notes:
Described in 1988 by South African botanists
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Lavranos and
Douglas Goode, who recognised
that the blue-leaved Transvaal cycads previously all included in E.
eugene-maraisii fell into a number of clearly morphologically distinct
and geographically separated populations (see also E. dyerianus and
E. middelbergensis). Similar observations were published more or less
simultaneously by Robbertse et al. (1990), resulting in creation of the
redundant names E. graniticola and E. verrucosus. E.
hirsutus is another more recently recognised member of this group.
Distinguishing features:
Distinguished within a group of blue-leaved Transvaal species by the
untidily twisted leaves with recurved tips, the entire leaflets, the
lower 1-2 pairs of leaflets reducing in size but remaining entire,
a clear petiole 9-14 cm long, and green, glabrous cones. This group
of species is
distinguished from the blue-leaved species of the Cape Province (E.
lehmannii and allies) by the almost concolorous leaves with stomata on
both surfaces.
Distribution and habitat:
Southern Transvaal Province, South Africa, restricted to a very small
population in the Drakensberg Mountains, in grassland on shallow soils over
dolomite ridges
Conservation:
1997 IUCN Red List of Threatened Plants
category E.
Description:
Plants arborescent; stem 2 m tall, 40 cm diam.
Leaves 60-80 cm long, blue or silver, dull, moderately keeled; rachis
blue, straight, stiff, slightly twisted in some leaves; petiole straight, with
1-6 prickles; leaf-base collar prominent; basal leaflets reducing to spines.
Leaflets lanceolate, concolorous, not lobed, insertion angle obtuse
(45-80°); margins flat; upper margin entire (no teeth); lower margin
entire (no teeth) to lightly toothed (1-3 teeth); median leaflets 12-17 cm long,
10-14 mm wide.
Pollen cones 1-4, narrowly ovoid, green, 35-50 cm long, 10 cm diam.
Seed cones 1-4, ovoid, blue-green, 30-45 cm long, 18-25 cm diam.
Seeds oblong, 30-35 mm long, 18-20 mm wide, sarcotesta yellow.