Distephanus qazmi, recently discovered on the island of Socotra, c. 250 km off the Horn of Africa, is described as a species new to science. The palaeotropical genus Distephanus, which has its greatest diversity on Madagascar, differs from all other genera of the Vernonieae in having yellow flowers. D. qazmi combines yellow flowers with presence of a basal stylar node, unstructured, elongate, polarized thickening of the median endothecial cells, calcarate-caudate anther appendages and ‘type A’ pollen, whereas trinervate leaves with strongly ascending basal secondary veins as in some Distephanus species and, within the Vernonieae, restricted to this genus, are not present in the new species. Within Distephanus, the new species is unique in its scapose habit and uniseriate pappus. The pappus of D. qazmi is, moreover, plumose, a feature known from a single other Distephanus species, D. plumosus from Kenya, Ethiopia and Somalia, which is possibly its closest relative. The habit and diagnostic features of the new species are illustrated.
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7 August 2000
Studies in the Compositae of the Arabian Peninsula and Socotra — 5. Distephanus qazmi (Vernonieae, Gymnantheminae) , a remarkable new species from the island of Socotra, Yemen
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