Computer-generated Keys to the Flora of Egypt. 9. The Spiny Taxa of Asteraceae

Abstract

FRESH and herbarium specimens of 158 species and infra-specific taxa belonging to 77 genera, including the newly recorded Helenium amarum (Raf.) H. Rock var. amarum, Pulicaria dysenterica (L.) Gaertn. and Orbivestus cinerascens (Sch. Bip) H.Rob., were assembled to represent the spineless members of the Asteraceae in the flora of Egypt. Morphological variations in the stems, leaves, capitula, phyllaries and achenes of every taxon were recorded comparatively as 83 characters with 195 character-states in a data matrix and subjected to analysis under the key-generating suit of computer programs DELTA. Of the 83 characters, 56 are binary, while the rest are ordered multi-states; measureable characters were categorized into the latter type to allow for possible variation in the value of the same character in different specimens of the same taxon. A conventional key to all taxa was obtained together with detailed and item descriptions. The detailed descriptions are too voluminous and only the key and item descriptions are provided. The item descriptions, in conjunction with the list of characters, can be used to re-synthesize the detailed descriptions and to reconstruct the original data matrix which can be manipulated to accommodate additional characters and/or taxa. The key and descriptions have a number of advantages over all of their predecessors.