20 (40)cm, extremely rare and highly endangered species native to few sites on the South-Western part of the Cañadas depression, Tenerife, where it grows at an elevation of up to 2.200 m. Frost-resistant to -5°C at night in its habitat during winter, but supposedly not winter hardy in Europe, unless cultivated in an unheated green-house, providing shelter from excessive humidity. Very unusual species as stems and leaves are highly succulent, densely covered with white hairs. Bright yellow flowers in June/July. This species requires extra drainage and careful watering, and is best grown in pure grit sand or lava. Southern side of Valle de Ucanca (2.000m).