Acantholimon joharchii, a new species of Acantholimon sect. Acantholimon (Plumbaginaceae) from Iran

Abstract

Acantholimon joharchii, a new species from northeastern Iran, is described and illustrated. The species belongs to Acantholimon sect. Acantholimon and is characterized by monomorphic, persistent leaves and one-flowered spikelets. It is morphologically most similar to A. gillii but differs in having oblong-obovate bracteoles that are distinctly shorter than the calyx tube, a longer calyx tube (6–6.5 mm), and calyx veins reaching the margin of the limb. A. joharchii occurs in mountainous habitats, on shallow, gravelly, and rocky soils. The species appears to have a very narrow distribution and may require conservation attention. Diagnostic characters, morphology, and habitat of the new species are discussed, highlighting its distinctiveness from related taxa.