Encephalartos gratus
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Encephalartos gratus |
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| Prain |
Encephalartos gratus is a member of the cycads (Cycadales) and belongs to the genus of bread palm ferns ( Encephalartos ).
features
The trunks stand individually, are spherical or up to 1.2 meters high and 60 cm wide. The cataphylls are triangular, gradually pointed, 8 to 12 cm long, 3 to 4 cm wide at the base and mostly woolly hairy on the underside. The numerous leaves are arched, lanceolate or linear, 0.9 to 1.8 m long and 34 to 44 cm wide; they are flat with a rounded tip and an abruptly narrowing base. The petiole is 10 to 12 cm long, has a swollen base and is densely hairy brown. The rachis is slightly conical, smooth or provided with slight furrows. The leaflets are in 30 to 70 pairs; they do not overlap, are dull green, pliable, straight or curved forward. The basal leaflets are reduced to thorns . The middle leaflets are lanceolate, 18 to 26 cm long and 23 to 35 mm wide; the upper edge has two to seven thorns, the lower one no or up to six thorny teeth.
The female cones are single or up to ten. They are cylindrical to almost conical, 55 to 68 cm long and 15 to 20 cm in diameter. The color is dark brown. The stem is 11.2 to 13.7 cm long and 5 to 7.5 cm in diameter. The middle sporophylls are around 30 mm high and 56 mm wide. The sarcotesta of the seed is dull vermilion at maturity, the sclerotesta is ovate, 30 to 37 mm long, 19 to 210 mm in diameter and more or less smooth with 11 to 14 indistinct longitudinal furrows.
The male cones stand individually up to five. They are egg-shaped to spindle-shaped, 30 to 40 cm long and 7.5 to 10 cm in diameter. The cones are densely hairy red-brown. The stem is 15 to 17.5 cm long, hairy and dull yellow-green with deep red spots. The middle sporophylls are 19 mm high and just as wide. The sporangia stand in a single, somewhat heart-shaped patch.
Distribution and locations
Encepalartus gratus is native to Malawi and occurs on Mount Mulanje. More recent finds come from Mozambique near Mavita and in the Serra Namuli in the northeast of Gurué .
It grows in rocky gorges and on rocky river banks, often in crevices with no visible soil. It also occurs in the savannah , where the plants are defoliated by the annual fires. It occurs at altitudes from 675 to 925 m in areas with 1000 to 1750 mm annual, predominantly summer precipitation. The temperatures regularly reach 35 to 38 ° C. The species is not considered endangered.
History of discovery and systematics
The first reports of cycads in the area were in 1899, specimens of herbarium were sent to Kew Gardens . The species was first described by David Prain in 1916 . The closest related species are not exactly known. These are likely to be Encephalartos hildebrandtii and Encephalartos manikensis , there are transitional forms to the latter.
supporting documents
- Loran M. Whitelock: The Cycads. Timber Press, Portland OR 2002, ISBN 0-88192-522-5 .
Individual evidence
Web links
- Encephalartos on Cycad Pages of the Royal Botanic Gardens Sydney, accessed April 25, 2008.
- Encephalartos gratus onthe IUCN 2013 Red List of Threatened Species . Listed by: Donaldson, JS, 2009. Retrieved April 28, 2014.