Aloe subacutissima

Overview

Aloe subacutissima is a branching aloe of south-central Madagascar, growing on sandstone or granite rocky sites. It offsets to form clumps, and sources describe leaf colours ranging from green to light brown, blue-pink and blue-violet. [1, 2, 3]

Key characteristics

Growth form

Stems branch and may be erect, divergent or decumbent, reaching up to 100 cm and about 3 cm thick. Plants offset and form clumps of 1–5 individuals or more. [2, 3]

Leaves

Leaves are 8–30 cm long and 3–7 cm wide, green, light brown, blue-pink or blue-violet, sometimes with white spotting. Marginal teeth are triangular and usually separate, but may become almost fused. [3]

Inflorescence and flowers

The inflorescence is 30–70 cm high with 1–3 branches. Racemes are 10–20 cm long; flower density is described as dense in one source and sparse in another. The perianth is scarlet and 28 mm long. [3, 2]

Distribution

WCVP places the species in south-central Madagascar. J.-B. Castillon & J.-P. Castillon (2025) report it from Anosy and Androy, while Carter et al. (2011) report Tuléar and Fianarantsoa. [1, 2, 3]

Habitat

It grows on rocky ground and inselbergs, with records from sandstone and granite substrates. Carter et al. (2011) place it between 600 and 1,000 m elevation. [2, 3]

Classification and nomenclature

Accepted name: Aloe subacutissima G.D.Rowley [1]
Protologue bibliography: Rowley (1973), Natl. Cact. Succ. J. 28: 6. [1, 3]
Type locality and type material: Perrier de la Bâthie 12690; holotype P00413853 and isotype P00413854 (P), from Anosy, Betroka District, between Itrongay and Betroka at 600 m. [3]
Basionym: Aloe deltoideodonta var. intermedia H.Perrier [3, 1]
Synonyms: Aloe deltoideodonta subsp. brevifolia (H.Perrier) Rebmann [1]

Aloe deltoideodonta var. brevifolia H.Perrier [1]
Illegitimate names: Aloe horombensis J.-P.Castillon [1]

Aloe intermedia (H.Perrier) Reynolds [1]

Main references

World Checklist of Vascular Plants (WCVP).
Carter, S., Lavranos, J.J., Newton, L.E. & Walker, C.C. (2011). Aloes: The Definitive Guide. Royal Botanic Gardens, Kew. pp. 217, 564, 708.
Castillon, J.-B. & Castillon, J.-P. (2025). Révision taxonomique du groupe de plantes du sud malgache appartenant au complexe Aloe deltoideodonta Baker (Asphodelaceae). Adansonia 47(23): 363–376. DOI
Grace, O.M., Klopper, R.R., Figueiredo, E. & Smith, G.F. (2011). The Aloe Names Book. Strelitzia 28. South African National Biodiversity Institute, Pretoria. pp. 46–47, 110.
Castillon, J.-B. & Castillon, J.-P. (2010). Les Aloe de Madagascar / The Aloe of Madagascar. J.-P. Castillon. 400 pp.

Updates

Classification, distribution and descriptive information are revised as new sources are verified or taxonomic treatments change.