Carthamus L.
The generic circumscription of Carthamus is controversial. As a result of molecular phylogenetic studies its boundaries were broadened. It now counts ca. 55 species and includes, among others, Carduncellus Adans. (Vilatersana & al. 2000; subsequently followed by most authors, e.g. Greuter 2003, Mabberley 2008, Tison & de Foucault 2014). In its traditional, narrow sense Carthamus only counted 14 species (Hanelt 1963) and some recent authors prefer to maintain a slightly adapted, narrow circumscription (López González 2012, 2014). The genus is native to the Old World (primarily in the Mediterranean area but extending to Central Asia).
A few species are economically important: Carthamus lanatus and some related species have become nearly cosmopolitan weeds of arable land while C. tinctorius is an oilseed crop (see also Mabberley 2008 for additional uses).
1 Stem arachnoid-hairy. Leaves deeply lobed to pinnatifid. Flowers always yellow. Pappus present (scaly) === Carthamus lanatus
Stem glabrous. Leaves entire or toothed. Flowers red, orange or yellow. Pappus usually absent === C. tinctorius
References
Ashri A. & Knowles P.F. (1959) Further notes on Carthamus in California. Leafl. W. Bot. 9: 5-8.
Ashri A. & Knowles P.F. (1960) Cytogenetics of safflower (Carthamus L.) species and their hybrids. Agron. J. 52: 11-17.
Greuter W. (2003) The Euro+Med treatment of Cardueae (Compositae) – generic concepts and required new names. Willdenowia 33: 49-61. [available online at: http://www.bioone.org/doi/pdf/10.3372/wi.33.33104]
Hanelt P. (1963) Monographische Übersicht der Gattung Carthamus L. (Compositae). Feddes Repert. 67: 41-180.
Hanelt P. (1976) Carthamus. In: Tutin T.G. & al. (eds.), Flora Europaea, vol. 4. Cambridge University Press, Cambridge: 302-303.
Keil D.J. (2006) Carthamus. In: Flora of North America Editorial Committee (eds.), Flora of North America, vol. 19. Oxford University Press, New York-Oxford: 178-181. [available online at: http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=105754]
Khidir M.O. & Knowles P.F. (1970a) Cytogenetic studies of Carthamus species (Compositae) with 32 pairs of chromosomes. I. Intrasectional hybridization. Amer. J. Bot. 57: 123-129.
Khidir M.O. & Knowles P.F. (1970b) Cytogenetic studies of Carthamus species (Compositae) with 32 pairs of chromosomes. II. Intersectional hybridization. Canad. J. Genet. Cytol. 12: 90-99.
Lambinon J., Delvosalle L., Duvigneaud J. (avec coll. Geerinck D., Lebeau J., Schumacker R. & Vannerom H. (2004) Nouvelle Flore de la Belgique, du Grand-Duché de Luxembourg, du Nord de la France et des Régions voisines (Ptéridophytes et Spermatophytes). Cinquième édition. Jardin botanique national de Belgique, Meise: CXXX + 1167 p.
López González G. (1990) Acerca de la clasificación natural del género Carthamus L. s.l. Anales Jard. Bot. Madrid 47: 11-34. [available online at: http://dialnet.unirioja.es/servlet/articulo?codigo=2956780]
López González G. (2012) Sobre la clasificación del complejo Carthamus-Carduncellus (Asteraceae, Cardueae-Centaureinae) y su tratamiento en Flora Iberica. Acta Botanica Malacitana 37: 79-92. [available online at: http://www.biolveg.uma.es/abm/Volumenes/vol37/37_Lopez-Gonzalez.pdf]
López González G. (2014) Carthamus. In: Devesa J.A. (eds.), Flora Iberica, vol. XVI(I). Madrid, Real Jardín Botánico, CSIC: 304-313. [available online at: http://www.floraiberica.es/floraiberica/texto/pdfs/16_159_027_Carthamus....
Mabberley D.J. (2008) Mabberley’s plant-book (3th ed.). Cambridge University Press, Cambridge: XVIII + 1021 p.
Tarıkahya-Hacıoğlu B., Karacaoğlu Ç. & Özüdoğru B. (2014) The speciation history and systematics of Carthamus (Asteraceae) with special emphasis on Turkish species by integrating phylogenetic and Ecological Niche Modelling data. Pl. Syst. Evol. 300(6): 1349-1359.
Tison J.-M. & de Foucault B. (coord.) 2014) Flora Gallica. Flore de France. Editions Biotope, Mèze : xx + 1196 p.
Vilatersana R., Garnatje T., Susanna A. & Garcia-Jacas N. (2005) Taxonomic problems in Carthamus (Asteraceae): RAPD markers and sectional classification. Bot. J. Linn. Soc. 147(3): 375-383.
Vilatersana R., Susanna A., Garcia-Jacas N. & Garnatje T. (2000) Generic delimitation and phylogeny of theCarduncellus-Carthamus complex (Asteraceae) based on ITS sequences. Plant Systematics and Evolution 221(1): 89-105.
Vilatersana R., Susanna A., Garcia Jacas N. & Garnatje T. (2000) Karyology, generic delineation and dysploidy in the genera Carduncellus, Carthamus and Phonus (Asteraceae). Bot. J. Linn. Soc. 134(3): 425-438.