Growth form and comparative characters
Plants have fibrous roots and form loose clusters. Stem-segment shape and size vary between individuals. Small, nearly globular segments occur alongside elongated, ovoid ones. Predominantly straight spines help distinguish the populations studied from C. unguispina, whose spines are often wavy. The structure of the pericarpel, the stem-derived covering of the ovary, is also important for identification. [Pauca-Tanco and Quipuscoa 2020]
Lomas Camaná and Islay
The revision gives a range covering Peru and Chile. In Arequipa, sites are concentrated in the Camaná and Islay lomas at 30–1058 m elevation. Plants occupy lower hill slopes, leeward slopes and summits, on sandy and locally stony substrates. These are areas with sparse vegetation and relatively little moisture input from fog and occasional drizzle. [Pauca-Tanco and Quipuscoa 2020]
Flowering and fruit set
The authors recorded flowering in November and February, with rare fruiting in the material observed. Flowers were visited by hymenopterans and beetles. The fruit has a dry chamber and seeds have a pale funicular covering. These characters link the species to other cumulopuntias. [Pauca-Tanco and Quipuscoa 2020]
Extent of variation
Stem-segment size was described more narrowly in older descriptions than in the 2020 field material. The revision documents individuals with distinctly elongated segments, so diameter or a globular growth shape alone does not exhaust the diagnosis. A combination of root, areole, spine and fruit characters is more valuable. [Pauca-Tanco and Quipuscoa 2020]
Synonyms and names in the literature
Maihueniopsis rahmeri · Opuntia campestris · Opuntia leucophaea · Opuntia rahmeri · Sphaeropuntia leucophaea · Sphaeropuntia sphaerica subsp. leucophaea · Tephrocactus campestris [2-WWW]