Notes on Kalanchoe rotundifolia (Haw.) Haw. (Crassulaceae) in Southern Africa: The Taxonomy of a Species Complex

Abstract

Taxonomically, Kalanchoe rotundifolia (Haw.) Haw. (Crassulaceae) is one of the most complex of the southern African representatives of the genus. The expression of its vegetative morphology, especially leaf shape and plant size, is exceedingly variable. The reproductive morphology is more constant in terms of the size and shape of the corolla tube and lobes, as well as in the upper part of the corolla tube and lower part of the corolla lobes invariably becoming twisted at the post-anthesis stage. However, flower colour ranges from a yellow-infused light orange through pinkish-red to scarlet. At present we conclude that treating the species as a variable complex in southern and eastern Africa, as well as Socotra, is taxonomically the most sensible. We provide an amplified description and geographical distribution map for K. rotundifolia, and discuss and illustrate some of the remarkably variable forms. A neotype is designated for the name Kalanchoe integerrima Lange.