Astroloba spiralis

Astroloba spiralis is a compact Astroloba species, with upright, erect stems that are densely covered in pointed succulent leaves. Stems are roughly 15 cm in diameter, and reach a height of 200mm.

The leaves are blue-green to grey in colour, they grow in 5 rows that sometimes form a gentle spiral. The leaves also have smooth surfaces (unlike the tubercled leaves of Astroloba bullulata and Astroloba corrugata). Each leaf typically has an oblique keel near the point. The flowers appear in autumn (December to May).

This species is easily confused with its close relative, the rare Astroloba herrei. Both plants also have inflated, puffed up flowers (perianths). However the flowers of Astroloba spiralis are wrinkled (transversely rugose), and not smooth like those of herrei. Spiralis is also genetically distinct, being a tetraploid. Usually spiralis also has more erect leaves (unlike the more spreading leaves of A.herrei) but this is not a rule, and only the flowers can be used to distinguish these two species with certainty.

A variety of this plant was occasionally recognised as a separate species, Astroloba pentagona, that bears its leaves at a 45 degree angle from the stem, in 5 rows, and has tiny tubercles on the leave margins and keels (of which each leaf may have several). It is now recognised to be merely a variety of A. spiralis.[2]

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  Astroloba spiralis in cultivation - locality Calitzdorp
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  Astroloba spiralis in habitat
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  The wrinkled ("rugose") flowers of A. spiralis.
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  Astroloba spiralis, from an 1812 botanical drawing

It is indigenous to the "Little Karoo", on the southern edge of the Karoo region of South Africa. It extends through the Little Karoo from the Graaff Reinet District in the Eastern Cape Great Karoo, as far as Oudtschoorn and Calitzdorp in the Western Cape, where it becomes Astroloba smutsiana.[3]

Wikimedia Commons has media related to Astroloba spiralis.

Wikispecies has information related to Astroloba spiralis.

• Astroloba spiralis - Introduction and images
• Astroloba spiralis - SANBI redlist