''Astroloba herrei'' is a small

succulent plant In botany, succulent plants, also known as succulents, are plants with parts that are thickened, fleshy, and engorged, usually to retain water in arid climates or soil conditions. The word ''succulent'' comes from the Latin word ''sucus'', meani ...

of the genus ''

Astroloba ''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. ...

'', restricted to the area around the

Swartberg mountains The Swartberg mountains (''black mountain'' in Afrikaans) are a mountain range in the Western Cape province of South Africa. It is composed of two main mountain chains running roughly east–west along the northern edge of the semi-arid Little Kar ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...

. It is listed as a

Vulnerable species A vulnerable species is a species which has been Conservation status, categorized by the International Union for Conservation of Nature as being threatened species, threatened with extinction unless the circumstances that are threatened species, ...

on the Red List of the South African National Biodiversity Institute (SANBI).

Description

''Astroloba herrei'' is a compact ''

'' species, with stems growing up to 20 cm high, that are densely covered in pointed succulent leaves. Flowers appear from June to November. With its sharp, grey-green, keeled leaves, and its puffed up, inflated flowers, the species is easily mistaken for the closely related ''

Astroloba spiralis ''Astroloba spiralis'' is a small succulent plant of the Astroloba genus, endemic to the southern Karoo regions of the Western and Eastern Cape Provinces, South Africa. Description ''Astroloba spiralis'' is a compact ''Astroloba'' species, wit ...

'' species. However it is genetically distinct and can always be distinguished by its flowers and its phyllotaxis. Both ''spiralis'' and ''herrei'' have puffed up, inflated flowers, but those of ''herrei'' are smooth (unlike ''spiralis'', which has a wrinkled, transversely rugose,

perianth The perianth (perigonium, perigon or perigone in monocots) is the non-reproductive part of the flower, and structure that forms an envelope surrounding the sexual organs, consisting of the calyx (sepals) and the corolla (petals) or tepals when ...

Other less reliable ways of identifying ''herrei'' are the fine, dark, longitudinal lines (striations) which are sometimes visible below the surface of the leaves, and the slight blueish colour which herrei attains in sheltered or shaded environments. Leaves often feature narrowly

acuminate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...

leaf tips that spread outwards more strongly than in ''spiralis''. However these are not certain ways of identifying it. Other than by its flowers, the only sure way of distinguishing this species is by its

phyllotaxis In botany, phyllotaxis () or phyllotaxy is the arrangement of leaf, leaves on a plant stem. Phyllotactic spirals form a distinctive class of patterns in nature. Leaf arrangement The basic leaf#Arrangement on the stem, arrangements of leaves ...

. The divergence angle of ''A. herrei'' is much smaller than that of ''A. spiralis''. This means that the five leaf-ranks of ''A. herrei'' will spiral in a direction counter to the direction of the generative spiral. Those of ''A. spiralis'' and ''A. spirella'' (among others) spiral in the same direction as the generative spiral. A variety of this plant was formerly recognised as a separate species, '' Astroloba dodsoniana'' (Uitewaal). The dark longitudinal stripes of this variety of ''herrei'' are faint or even invisible, and the leaves are slightly paler. This is just a growth form and it can appear at random among normal ''herrei'' plants in all ''herrei'' populations.

Distribution

This species has historically been considered rare, disjunct and restricted to small populations near Uniondale in the

Little Karoo The Karoo ( ; from the Afrikaans borrowing of the South Khoekhoe !Orakobab or Khoemana word ''ǃ’Aukarob'' "Hardveld") is a semi-desert natural region of South Africa. No exact definition of what constitutes the Karoo is available, so its ext ...

, and the widely separated Prince Albert in the

Great Karoo The Karoo ( ; from the Afrikaans borrowing of the South Khoekhoe !Orakobab or Khoemana word ''ǃ’Aukarob'' "Hardveld") is a semi- desert natural region of South Africa. No exact definition of what constitutes the Karoo is available, so its ex ...

. In 2017 its distribution was revised when it was found to be widespread in the more remote areas north of the Swartberg mountains. The species is listed as Vulnerable - partly because it was believed to have a very restricted range, and partly because it is threatened by

habitat destruction Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

and illegal collecting. In habitat, it grows on Karoo flats, often underneath bushes which provide it with some protection from the sun.S.Molteno (2018) ''Prince Albert's Astroloba''. Haworthiad 32, 1. ISSN 1359-1614

References

External links

Astroloba herrei - Introduction and images

Astroloba herrei - SANBI redlist
{{Taxonbar, from=Q751625 herrei Flora of the Cape Provinces