Wahlenbergia roxburghii
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Wahlenbergia roxburghii (Syn. Wahlenbergia burchellii ) |
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Wahlenbergia roxburghii is an extinct plant species from the genus of the bog bells ( Wahlenbergia ) within the bluebell family . It was endemic to St. Helena . The species name honors the Scottish botanist William Roxburgh . The species was described by Alphonse Pyrame de Candolle in 1830. Anindependent formalso described by de Candolle in 1839 as Wahlenbergia burchellii wassynonymouswith Wahlenbergia roxburghii in 2012.
features
Wahlenbergia roxburghii was a shrub that reached a stature height of 50 to 90 centimeters. The pachycaule trunk was not very branched. The young branches were finely haired. The semi-sitting, finely hairy leaves were 8 to 14 inches long and 2 to 3.5 inches wide. The leaf blade was wedge-shaped-lanceolate or oblong-lanceolate. The leaf margin was notched to finely serrated. The inflorescence was a narrow terminal, finely hairy panicle. The upright inflorescence axis was hairy and had lanceolate, pointed bracts that were 14 mm long and 2 mm wide. The white flowers were 10 to 12 mm in diameter. The calyx was bare. The ovate-lanceolate, somewhat pointed, whole-margined calyx lobes were 4 to 4.5 mm long and 1 to 1.5 mm wide. The white corolla was deep five-lobed. The elongated flower tube and the corolla lobes were approximately 5 mm long. The elongated ovary was two-chambered. The capsule fruit was oblong-inverted-cone-shaped.
Occurrence
Wahlenbergia roxburghii occurred in the central mountains of St. Helena. Documented sites are the thicket forests on the southern slopes of Diana's Peak , the dense forests on Halley's Mount and the Sandy Bay mountain range near Taylor's Flat.
die out
Wahlenbergia roxburghii was last detected in 1872 by John Charles Melliss , the form described as Wahlenbergia burchellii last in 1877. Possible causes for its extinction were the destruction of vegetation by goats and the displacement by New Zealand flax ( Phormium tenax ).
Individual evidence
- ↑ Phil Lambdon: Flowering plants & ferns of St Helena . Pisces Publications for St Helena Nature Conservation Group, Newbury, Berkshire, 2012. ISBN 978-1-8743-5752-0
literature
- QCB Cronk: The endemic Flora of St Helena. Anthony Nelson, Oswestry, 2000, ISBN 0-904614-35-2 .