REVISION OF ANACYCLUS 



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Fig. 13 Distribution of Anacyclus pyrethrum () and A. maroccanus (A). 



of A. pyrethrum. The second seems to be an aberrant cultivar. Therefore specimen 18 is chosen 

 as the lectotype. 



Variation: Anacyclus pyrethrum is perhaps the most distinctive species of the genus, since it 

 possesses several morphological and biological features not shared by other species. Amongst 

 the prominent morphological features are the submerged woody caudex, the heteromorphic 

 leaves, the unusual prostrate inflorescence and the tough thickened cypselas. From a biological 

 point of view, it appears to be the only species with a self-compatible breeding system (Uitz, 

 1970; Humphries, in press a) and occasionally has vestigial stamens in the normally female 

 ligulate florets, suggesting its derivation from a homogamous hermaphrodite form. The 

 cypselas are remarkably persistent at maturity and this, coupled with the fact that the receptacular 

 scales overtop the cypselas so that they touch the next layer of bracts, makes the whole capitulum 

 into a hard, round, almost woody head. Consequently it is often dispersed as a complete diaspore. 



A. pyrethrum can be compared with the annual species A. maroccanus, since they share a 

 number of plesiomorphous features, the most striking of which is the white ligules with the red 

 stripe below. The hypothesis that they represent sister species should be tested as and when live 

 material becomes available. The possibility that they have a recent common ancestry cannot be 

 completely ruled out, especially in the light of their apparent vicariant distribution (Fig. 13). 



A. pyrethrum is a very variable species, often occurring in small discrete montane populations. 

 Formerly it was recognized as two species, A. pyrethrum and A. depressus Ball, the former usually 

 being taken to comprise the more robust forms from Algeria and the eastern Moyen Atlas 

 mountains of Morocco, which have longer stems, large capitula, longer ligules, harder fruits and 

 generally larger vegetative parts, whereas the latter, variously called A. feyni Porta & Rigo, 

 A. pyrethrum var. subdepressus Doumergue, var. depressus (Ball) Mai re and var. microcephalus 

 Maire, includes those shorter, less robust and occasionally hairier plants with small, but more 

 numerous capitula, shorter ligules and smaller, softer cypselas, which occur in higher and drier 

 habitats of western Algeria and the Sierra de Alcaraz, the Haut Atlas, the Anti-Atlas and the 

 eastern Moyen Atlas. All the material of A. pyrethrum will fit into one of these form series; 

 but since it is possible to find in the Moyen Atlas and parts of Algeria populations with plants 

 which will fit into either series, to consider them as separate species or subspecies is artificial. 



