Convolvulus caput-medusae Lowe on Fuerteventura (Canary Islands, Spain)
Convolvulus caput-medusae is an endemic plant species of the Canary Islands growing only on Fuerteventura and Gran Canada. Because this species is highly threatened, the till now little known populations of Fuerteventura have been investigated. The population is minimum 50.000 individuals. The size distribution has been investigated by certain parts of subpopulations. The maximum height was 56 cm, the maximum diameter 125 cm. Convolvulus caput-medusaeis associated with other shrubs and subshrubs in communities belonging probably to the class Pegano-Salsoletea respectively to the new class Polycarpaeo niveae-Traganetea moquini. It grows on rocky plateaus covered with a shallow layer of carbonate sand in the Convolvulus caput-medusae - Ononisnatrix ssp. ramosissima community, whereas on steep rocky slopes in direct contact to the sea it grows in the Chenoleo tomentosae-Suaedetum vermiculatae. Both communities are documented by plant sociological releves. The need for further investigations is pointed out.