New cactus records from Gran Canaria with a key to the opuntioid species now established in the Canary Islands (Spain)

Further field work in Gran Canaria (Canary Islands, Spain) yielded new records of escaped cacti. Opuntia elatior, O. engelmannii, O. phaeacantha, O. stricta, Oreocereus pseudofossulatus, Pilosocereus polygonus, Thichocereus cuzcoensis and T. pachanoi are reported for the first time from Gran Canaria. A spontaneous hybrid between two invasive species (O. ficus-indica and O. robusta) was recorded in two localities. Several of these taxa appear to be firmly established while others are considered casuals, at least at present. Austrocylin-dropuntia cylindrica - a species formerly considered doubtful in the Canary Islands - is confirmed from Gran Canaria. New records are presented for three recently detected, naturalized or invasive species: Cylindropuntia bigelovii, C. prolifera and Opuntia lindheimeri. All newly detected taxa are illustrated and a key for the identification of the opuntioid species reliably recorded so far in the Canary Islands is presented.