科研之友
微信
新浪微博
Facebook
分享链接
摘要
Following field and herbarium investigation of the subequatorial African and mainly western southern African Ferraria Burm. ex Mill. (Iridaceae: Iridoideae), a genus of cormous geophytes, we recognize 18 species, eight more than were included in the 1979 account of the genus by M.P. de Vos. One of these, F. ovata, based on Moraea vain Thunb. (1800), was only discovered to be a species of Ferraria in 2001, and three more are the result of our different view of De Vos's taxonomy. In tropical Africa, F. glutinosa is recircumscribed to include only mid- to late summer-flowering plants, usually with a single basal leaf and with purple to brown flowers often marked with yellow. A second summer-flowering species, F. candelabrum, includes taller plants with several basal leaves. Spring and early summer-flowering plants lacking foliage leaves and with yellow flowers from central Africa are referred to F. spithamea or F. welwitschii respectively. The remaining species are restricted to western southern Africa, an area of winter rainfall and summer drought. We recognize three new species: F. flava and F. ornata from the sandveld of coastal Namaqualand, and F. parva, which has among the smallest flowers in the genus and is restricted to the Western Cape coastal plain between Ganzekraal and Langrietvlei near Hopefield. Ferraria ornata blooms in May and June in response to the first rains of the season. Among the remaining species, F. uncinata subsp. macrochlamys is now F. macrochlamys and is treated as comprising three subspecies: subsp. macrochlamys from central and northern Namaqualand has leaves with thickened, crisped margins; subsp. kamiesbergensis from the southern Kamiesberg has leaves with unthickened margins and blades curved in one direction; and subsp. serpentina from gravels and sands of coastal Namaqualand has serpentine leaves, also with unthickened margins. Among the remaining species, F. divaricata subsp. arenosa is now treated as a synonym of F. divaricata. Because of our re-interpretation of the type of F. divaricata, plants which were called F. divaricata subsp. divaricata and subsp. australis are now treated as synonyms under the name F. variabilis. Flowers of Ferraria are unique in Iridaceae in having tepal limbs with crisped margins and a style that divides into flattened branches, each deeply forked with finely fringed adaxial margins. Despite relative floral uniformity, the genus displays a surprising ranee of discrete pollination systems for so small a genus. Pollinators include Diptera in the families Muscidae, Calliphoridae, and Sarcophagidae (F. crispa group); anthophorine and honey bees (F. ferrariola); eumenid wasps (F. divaricata, F. macrochamys, F variabilis); and Coleoptera in the families Meloidae and Melyridae (F. uncinata). Preliminary phylogenetic analysis using plastid DNA regions shows F. glutinosa to be sister to an unresolved cluster of southern African species and confirms as plesiomorphic the open branching habit, many-flowered inflorescences and exserted globose capsules that characterize F glutinosa and its immediate allies in subgen. Glutinosa.
- 出版日期2011-5
