Grevea eggelingii
| Grevea eggelingii | ||||||||||||
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| Grevea eggelingii | ||||||||||||
| Milne-Redh. |
Grevea eggelingii is a plant type from the genus Grevea . It occurs in East Africa .
description
Vegetative characteristics
Grevea eggelingii is a shrub or small tree with stature heights of usually 3.5 to 7.5 m (rarely even 1 m). They often form thickets through root saplings. The older trunks are gray-brown or grayish white, brittle and have fine longitudinal cracks and densely distributed cork pores . Heart-shaped leaf scars can be seen on the lower nodes . The younger branches are green and have white cork pores. Young buds are woolly hairy and sit in the leaf axils and on leafless nodes.
The leaves are opposite or almost opposite. Their leaf blade is hairless, elliptical or ovate, usually 3.5 to 23.5 cm (rarely only 1.3 cm) long and usually 1.4 to 14 cm (rarely only 0.6 cm) wide. Towards the front they are pointed with a short point, the base is narrowed and broadly wedge-shaped. The leaf margin is entire or occasionally slightly wavy. Four or five pairs of curved lateral nerves extend from the main artery. The petiole is 0.4 to 3 (rarely up to 5 cm) long.
Inflorescences and flowers
The male inflorescences are in the axils of the young leaves, they are more or less umbel-shaped cymes with up to eight flowers . The inflorescence stalk is 0.4 to 5 cm long , the flower stalks are 0.2 to 1.8 cm long. The calyx of the male flowers is about 1 to 2 mm long, the crown is white or yellowish-green in color, the individual petals are oblong or oblong - almost spatulate, rounded at the tip and slightly narrowed at the base. They are strongly bent back and very slightly jagged irregularly. They have a length of 4 to 5 mm and a width of 2.5 to 3 mm. The stamens consist of 1.2 to 1.5 mm (rarely up to 3 mm) long stamens and 2.5 to 3 mm (rarely only 1.6 mm) long anthers . There is a rudimentary ovary 0.9 to 1.5 mm in length.
The female flowers have a calyx with an 8 mm long calyx tube, which is slightly expanded at the base, is cylindrical towards the top and is irregularly bumpy. The flower stalk is 1 to 4 mm (rarely up to 8 mm) long. The calyx lobes are triangular and about 0.5 mm long. The petals are cream-colored, elongated and 3.5 to 4 mm long and 2.5 mm wide. The tip is rounded, the base slightly narrowed. They are strongly bent back and very slightly jagged irregularly. The stamens, which have retreated to staminodes , are 1 mm long. The thick, white stylus is long 3 (rare to 6 mm) to 4 mm, the cap-shaped at the top short di- (rarely three) and limp with ovoid, 1.8 to 2.5 mm long scar occupied.
Fruits and seeds
The fruits are bottle-shaped, 1.5 to 3 cm (rarely up to 3.5 cm) long and 1 to 1.6 cm wide. They are irregularly densely prickly-warty or finely prickly, but can also be smooth. There are also smaller, rounded warts on the widened part. The upper part is more or less smooth, at the top is the permanent style. The five to eleven (rarely four or twelve) seeds are reddish or yellowish brown, more or less round and indented. They are about 5 to 6 mm long, 5 mm wide and 2.5 to 3.5 mm high.
Chromosome number
The number of chromosomes is 2n = 24.
Systematics and occurrence
Three varieties are distinguished within the species :
- Grevea eggelingii var. Eggelingii , the fruits of which have 1 to 2 (rarely also up to 3) mm long warts or spines.
- Grevea eggelingii var. Echinocarpa Mendes , with fruits that are covered with 4 to 6 (rarely also up to 8) mm long warts or spines.
- Grevea eggelingii var. Keniensis (Verdc.) Verdc. , with smooth fruits.
The range of the species is in East Africa , the three varieties occur there both geographically separated from each other and together. The type specimen of Grevea eggelingii var. Keniensis and thus this variety occurring in Kenya was initially incorrectly assigned to the species Grevea madagascariensis .
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Individual evidence
Most of the information in this article has been taken from the sources given under literature; the following sources are also cited:
- ^ Grevea eggelingii at Tropicos.org. In: IPCN Chromosome Reports . Missouri Botanical Garden, St. Louis
- ^ A b Bernard Verdcourt: A Reappraisal of the Grevea (Montiniaceae) Growing on the Kenya Coast. In: Kew Bulletin. Vol. 51, No. 4, 1996, ISSN 0075-5974 , pp. 771-773, JSTOR 4119730 .
literature
- Bernard Verdcourt: Montiniaceae (= Flora of Tropical East Africa. ). Royal Botanic Gardens et al., Kew et al. 1973, ISBN 0-85592-026-2 .