noun, plural: areoles
(botany) A spot, which may be raised or depressed, on the cactus body where spines, hair, glochids, etc. arise from
(botany, entomology) An outlined space such as that forms on the surface of a leaf or on the wing of an insect
In botany, the term areole pertains to that spot or part of the cactus body where spines, hair, glochids, flowers, or branches arise from. It may be raised or depressed. It may be light or dark. The presence of areoles is an important feature of cacti and is used to distinguish them from other succulent plants.
The areole seems to be the equivalent to a bud. Many cactus species bear cluster of spines, which are vestigial leaves of cactus species, arising from the areoles. Others have glochids, which are fine, detachable bristles that provide additional protective function. Spines may also arise from the areoles. New branches have also been observed to grow from the areoles, such as those in Opuntioidiae and the saguaro.
For other usage of the term areole, it may be used to refer to that space created on the surface of a leaf or of an insect. In anatomy, it is an alternative form for areola.
Word origin: Latin areole (small space)
- areolate (adjective)