Aulacocalyx pallens
| Aulacocalyx pallens | |
|---|---|
 | |
| Aulacocalyx pallens subsp. letestui | |
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Embryophytes |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Gentianales |
| Family: | Rubiaceae |
| Genus: | Aulacocalyx |
| Species: | A. pallens |
| Binomial name | |
| Aulacocalyx pallens | |
| Subspecies[2] | |
| |
| Synonyms[2] | |
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Aulacocalyx pallens is a species of flowering plant in the family Rubiaceae. It is a tree with elliptical to obovate leaves, white flowers, and black fruits. The species is native to west-central Africa.
Aulacocalyx pallens was described in 1877, and is listed as Vulnerable by the IUCN.
Taxonomy
Aulacocalyx pallens was described by William Philip Hiern in 1877, and initially placed in the genus Randia.[2] In 1997, Diane Mary Bridson and Estrela Figueiredo moved it to the genus Aulacocalyx.[3][4]
There are two recognised subspecies:[2]
Distribution
Aulacocalyx pallens is native to the wet tropical biome of the Democratic Republic of the Congo, Gabon, and São Tomé.[1][2] Its extent of occurrence is estimated as 1,047,370 square kilometres (404,390 sq mi).[1]
The species grows in mature and secondary forests, at elevations of 180–1,100 metres (590–3,610 ft).[1]
Description
Aulacocalyx pallens is a tree that grows up to 18 metres (59 ft) high.[1] The branches are striped, and covered with short, soft hairs. The leaves are elliptical to obovate, 11–16 centimetres (4.3–6.3 in) long, and 3.5–6.5 centimetres (1.4–2.6 in) wide. When dry, the leaves are olive, light green, or brown. The leaves have domatia. The leaf stems are 3–6 millimetres (0.12–0.24 in) long.[4]
The inflorescences grow on 1.5–6 millimetres (0.059–0.236 in) stems, and usually have at least five flowers. The calyx tube is 2–2.5 millimetres (0.079–0.098 in) long, and has 0.2–0.5 millimetres (0.0079–0.0197 in) long lobes. The corolla is white, and 1.8–2.9 centimetres (0.71–1.14 in) long. The corolla has five elliptical to oblong lobes, which are 5–8 millimetres (0.20–0.31 in) long, and 2–2.8 millimetres (0.079–0.110 in) wide.[4]
The fruits are 8–10 millimetres (0.31–0.39 in) wide, and black when dry. The seeds are 5–6 millimetres (0.20–0.24 in) long, around 5 millimetres (0.20 in) wide, and black when dry.[4]
Conservation
In 2020, the IUCN assessed Aulacocalyx pallens as Vulnerable. Some populations are threatened by agriculture. The species is present in Parque Natural Obô de São Tomé.[1]
References
- 1 2 3 4 5 6 Paradis, A.-H.; Stévart, T. (2021). "Aulacocalyx pallens". IUCN Red List of Threatened Species. 2021 e.T62863A173324332. doi:10.2305/IUCN.UK.2021-3.RLTS.T62863A173324332.en. Retrieved 2026-07-27.
- 1 2 3 4 5 "Aulacocalyx pallens". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 2026-07-27.
- ↑ "Aulacocalyx pallens (Hiern) Bridson & Figueiredo". International Plant Names Index (IPNI). Royal Botanic Gardens, Kew; Harvard University Herbaria & Libraries; Australian National Botanic Gardens.
- 1 2 3 4 Figueiredo, Estrela (1997). "A Revision of Aulacocalyx (Rubiaceae-Gardenieae)". Kew Bulletin. 52 (3): 637–658. doi:10.2307/4110291. Retrieved 27 July 2026.
- ↑ "Aulacocalyx pallens subsp. letestui". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 2026-07-27.
- ↑ "Aulacocalyx pallens subsp. pallens". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 2026-07-27.