Jasminocereus

Morphological Summary

Jasminocereus is a monotypic genus of arborescent columnar cacti endemic to the Galápagos Islands (Ecuador), one of the most biologically unique volcanic archipelagos on Earth. Its single species, J. thouarsii, known as the Galápagos cactus or candelabra cactus, is an emblematic plant of the Galápagos ecosystem with a fascinating evolutionary history. The species evolved from a South American ancestor that colonized the islands and developed woody trunks with scaly reddish-orange bark to raise its photosynthetic pads and flowers beyond the reach of herbivorous reptiles, especially the Galápagos giant tortoises. The degree of arborization varies notably among island populations according to herbivory pressure: on tortoise-inhabited islands, stems reach 7 m; on islands without tortoises, plants remain shorter and more branching. Jasminocereus interacts closely with the Galápagos ecosystem: its flowers are visited by Darwin's finches and its fruits are a crucial food source for giant tortoises and land iguanas.