PLUMBAGINACEAE Juss.
Family comprised of 24 genera and about 635 species, mostly herbaceous, rarely shrubby or lianescent, distributed almost throughout the planet. In North Africa there are only 4 genera with shrubby species: Limoniastrum, Plumbago, Ceratolimon and Saharanthus, the latter two recently redefined by M.B. Crespo & Lledó (2000). The 2 species that now form the genus Ceratolimon M.B. Crespo & Lledó. are small shrubs that do not usually exceed 0.5 m in height.
C. weygandiorum (Maire & Wilczek) M.B. Crespo & Lledó (L. weygandiorum Maire & Wilczek), with slightly fleshy leaves, obovate, a little lobulate, is endemic to the coastal rocky cliffs of the Draa region.
C. feei M.B. Crespo & Lledó [L. feei (Girard) Batt.], in Arabic “Ouden el-hmar”, has entire lanceolate leaves, fleshier, and it is endemic to the NW continental Sahara.
None of these 2 species seems threatened. Currently, they have not been assessed at a global level on the IUCN Red List of Threatened Species.
Crespo, M.B. & Lledó, M.D. 2000. Two new North African genera related to Limoniastrum (Plumbaginaceae). Botanical Journal of the Linnean society, 132: 165-174.
Key to genera
1 Stems striated. Calyx angular, covered with visible glands Plumbago
1 Stalk non-striated. Calyx tubular, not angular, ± scarious but glandulous 2
2 External bract of the spikelets shorter than the inner bract, with white granulationson leaves, staminal filaments inserted at the throat of thecorolla tube Limoniastrum
2 External and internal bracts of the spikelets of the same length, without white granulationson leaves, staminal filaments inserted at the base of the petals 3
3 Leaves alternate, middle bract of the spikelets present Saharanthus
3 Leaves arranged in rosettes, middle bract of the spikelets absent Ceratolimon
Updated by: A.F. Carrillo & J. Charco.