Status of the southern African Anapalina and Antholyza (Iridaceae) genera, based solely on characters for bird pollination, and a new species of Tritoniopsis

Abstract

Anapalina N.E. Br. (1932), erected for several species of long-tubed, red-flowered species previously assigned to Antholyza L., is closely allied to Tritoniopsis L. Bol. (Lewis 1959a; Goldblatt 1971). Distinctive leaves with more than one main vein (unless very narrow), short coriaceous bracts, the inner longer than the outer, and inflated capsules and large seeds with a loosely to elaborately folded seed coat are synapomorphies uniting the two genera. In addition some species of both genera have unusual pseudopetiolate leaves. Shared, unusually high chromosome numbers, 2 n = 32 and 30, support the contention that Anapalina and Tritoniopsis constitute a single monophyletic lineage. The flower of Anapalina with its long dimorphic tube, exserted stamens and more or less hooded upper tepal conforms to the classic model for ornithophily and the genus represents no more than a series of species of Tritoniopsis adapted primarily for bird pollination. Segregation of genera based solely on this criterion has little merit and such treatment is inconsistent with the circumscription of other genera of subfamily Ixioideae. The suite of characters associated with ornithophily appears to have evolved several times in Ixioideae and until recently some natural species assemblages were accorded generic rank on the basis of the adaptations to ornithophily of their flower, while others were placed in genera with other types of floral adaptation. This paper is the second of a series dealing with genera of Ixioideae defined exclusively by characters associated with ornithophily. Original chromosome counts for the genus and a new species, Tritoniopsis williamsiana, are included here. Like Anapalina , the genus Antholyza [as currently circumscribed sensu Brown (1932) and thus excluding the lectotype species] is based on floral adaptations associated with ornithophily. Except for its flowers, it is indistinguishable from Babiana Ker-Gawl., in which it was first included by Ker (1804), and then later by Baker (1896). I recommend inclusion of Antholyza sensu Brown in Babiana, noting their shared plicate leaves, general pubescence or puberulence, and base numbers of x = 7. New combinations are provided for the species of Anapalina now included in Tritoniopsis while the nomenclature of the species until now included in Antholyza is outlined.