Astroloba is a genus of flowering plants in the family Asphodelaceae, subfamily Asphodeloideae,Stevens, P.F. (2001 onwards), "Asphodeloideae", Angiosperm Phylogeny Website, retrieved 2016-06-10 native to the Cape Province of South Africa.
Naming
The name of the genus is derived from the Greek words astros, star, and lobos, lobe, and refers to the starlike shape of the petals, which appear at the end of the tube-like flowers.
Description They are very closely related to the genus Haworthia, but are distinguished by their flowers being regular and not double-tipped. The flowers are small and white, and appear clustered on slender racemes., p. 17
They bear very regular, sharp, triangular, succulent leaves along their symmetrical columnar stems. The leaves are in a number of distinctive spiral arrangements.Molteno S. (2022). Phyllotaxis in Asphodelaceae subfam. Alooideae: a tool in taxon delimitation. Haseltonia 28(1), https://doi.org/10.2985/026.028.0107 They are slow growing, multi-stemmed, and their longer stems tend to sprawl in their rocky natural habitat.
Within the genus, various subgroupings can be recognised, based on shared characteristics. The Foliolosa Complex (including the entities robusta, foliolosa and congesta) can be distinguished by the glossy sheen to their leaves, and by their flowers with long bracts, short pedicels, smooth perianth tubes and broad cream-white lobes.
Distribution and habitat These species are restricted to the dryer inland regions of the southern Cape, South Africa. In their arid natural habitat, they tend to favour semi-shade positions, with well-drained soil and winter rainfall.Molteno, S., Smith, G., Van Jaarsveld, E. (2017) Extending the Natural Distribution Range of Astroloba herrei Uitewaal (Asphodelaceae: Alooideae): Implications for Its Conservation Status. Haseltonia 23:39–47, https://doi.org/10.2985/026.023.0106
Species , the World Checklist of Selected Plant Families accepted twelve species. An overall list of species recognised include the following:Molteno S., Smith G.F., Figueiredo E. (2018). A Synopsis of Astroloba Uitewaal (Asphodelaceae: Alooideae): Species, Types, and Infrageneric Classification. Haseltonia 25: 72-83, https://doi.org/10.2985/026.025.0106Search for "Astroloba", Pandora Roberts Reinecke: Genus Astroloba Uitewaal (Liliaceae). MSc thesis. UCT Department of Biological Sciences. 1965.Introduction to the Astroloba species
Astroloba bullulata (Jacq.) Uitewaal Astroloba pentagona (Haw.) Uitewaal (="hallii" nom. nud.) Astroloba congesta (Salm-Dyck) Uitewaal Astroloba corrugata N.L.Mey. & Gideon F.Sm. Astroloba cremnophila van Jaarsv. Astroloba foliolosa (Haw.) Uitewaal Astroloba herrei Uitewaal Astroloba robusta P.Reinecke ex Molteno, Van Jaarsv. & Gideon F.Sm.G.Smith, E.Figeueiredo, S.Molteno (2017): Astroloba robusta: A new species from the Great Karoo, South Africa. Bradleya 35, pp. 201-211. Astroloba rubriflora (L.Bolus) Gideon F.Sm. & J.C.Manning (also known as Poellnitzia rubriflora) Astroloba spiralis (L.) Uitewaal Astroloba spirella (Haw.) Molteno & Gideon F.Sm. (="smutsiana" nom. nud.) Astroloba tenax Molteno, van Jaarsv. & Gideon F.Sm.S.Molteno, E.van Jaarsveld, G.Smith. (2017): Astroloba tenax Molteno, Van Jaarsv. & Gideon F.Sm., a new species from the Groot Swartberg Mountain, South Africa. Bradleya 35, pp. 139-149.
Natural hybrids of these species occur, and there are several varieties which are unresolved as to whether they constitute intermediate forms, hybrids or separate species. In addition there are naturally occurring hybrids between species of Astroloba and Tulista (formerly Haworthia Robustipedunculares), including the well-known ones named × Astrolista bicarinata (formerly x Astroworthia bicarinata / skinneri) which are crosses between Astroloba corrugata and Tulista pumila.G.Smith, E.Figeueiredo, S.Molteno (2017): xAstrolista: A new name for the South African endemic nothogenus x Astroworthia. Bradleya 35, pp. 195-200.
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