spiny succulent Euphorbia spiralis

spiny succulent Euphorbia spiralisDescription: Euphorbia spiralis is a scrubby, leafless, cactus like succulent related to Euphorbia polyacantha. It is the only spiny succulent euphorbia on Socotra (a typical example of convergent evolution, morphologically strongly reminiscent of neotropical cacti), possessing thick succulent stems with rows of paired spines arranged along the longitudinal ridges. The specific epithet spiralis coined by Balfour refers to the spiralling of the stem in

Description: Euphorbia spiralis is a scrubby, leafless, cactus-like succulent related to Euphorbia polyacantha. It is the only spiny succulent euphorbia on Socotra (a typical example of convergent evolution, morphologically strongly reminiscent of neotropical cacti), possessing thick succulent stems with rows of paired spines arranged along the longitudinal ridges. The specific epithet spiralis coined by Balfour refers to the spiralling of the stem in specimens he observed, however, stems can be either straight or spiraling and, in fact, spiralling of the stem seems rather rare. A second species, Euphorbia septumsulcata, was separated by the greater number of stem angles. However, this seems to fall within the variation found in E. spiralis and so is not recognized as an independent species. Euphorbia spiralis individuals varies noticeably in shape some form few branched open shrub while other have a distinct cushion-like growth-form, with the stems densely packed.

Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz