Copiapoa cinerea subsp. columna-alba

Cechy diagnostyczne

The stem generally remains solitary and branches rarely. Rib numbers reach 40, exceptionally 50. The ribs are relatively flat, slightly wavy and up to about 1 cm wide. They give the surface a more densely ridged appearance than in typical C. cinerea. [Larridon et al. 2018, description of subsp. columna-alba]

In the comparative description, the flowers are distinguished by the absence of red tips and stripes on the outer perianth elements that characterise the nominate subspecies. The seeds are smaller on average. These features were assessed together with growth form and geography. [Larridon et al. 2018]

Range and habitat

The subspecies occurs in the coastal belt between areas south of Taltal and north of Chañaral. The 2018 account particularly identifies sandy valleys and coastal plains. The current POWO name is Copiapoa cinerea subsp. columna-alba. [Larridon et al. 2018] [2-WWW]

Measurements of inclination and temperature

Ehleringer and colleagues studied Copiapoa cinerea subsp. columna-alba (C. columna-alba in the publication). In a sample of 100 plants from Pan de Azúcar, 93 inclined within 20° of north. The mean angle of the stem axis relative to the horizontal was 51.9°, with a standard deviation of 8.6°. [Ehleringer et al. 1980, tabela 1, p. 64–65]

Measurements on 12 September 1978 showed strong heating of the apical stem zone. For much of the day, the apex temperature was about 30–40°C, while air temperature was about 13–20°C. The radiation model linked this balance to the direction and angle of the apical surface. The thematic article compares field data and model results. [Ehleringer et al. 1980, pp. 65–67]