Table S1. Genetic diversity in species of the genus Centaurea. Range size, Ploidy, and Biological traits as indicated by the authors (? = ploidy not available in the reference). Pop is the number of local populations used for genetic diversity estimates. Diversity values are Nei’s gene diversity unless otherwise indicated (I = Shannon information index).

Species / Range size / Pop. / Habitat and biological traits / Ploidy / Marker / Species/Population diversity / References
C. borjae / Endemic / 6 / Perennial herb, no pappus, enthomoplilous outcrosser, insect pollinated, sea cliffs, asexual reproduction. / 6x / AFLP / 0.258/0.192-0.258
I=0.413/I= 0.309-0.435 / This study
C. corymbosa / Endemic / 6 / Perennial, fruit with pappus, mostly self-incompatible, entomophilous outcrosser, limestone cliff, insect pollinated. / ? / Allozymes / 0.074/0.03-0.074 / (Colas et al. 1997)
Allozymes / 0.20/0.11-0.26 / (Fréville et al. 2001)
Microsatellites / 0.50/0.36-0.62 / (Fréville et al. 2001)
C. horrida / Endemic / 7 / Dwarf, long-living, sea cliffs, outcrossing, insect pollinated. / 2x / Microsatellites / No data/0.603-0.854 / (Mameli et al. 2008)
C. nivea / Endemic / 5 / Perennial, rhizomatous plant, calcareous soils. / 2x / RAPD / 0.296/0.244-0.258
I=0.451/ I=0.372-0.389 / (Sözen and Özaydin 2009)
C. wiedemanniana / Endemic / 6 / Perennial. / 2x / RAPD / 0.278/0.183-0.211
I=0.429/ I= 0.283-0.324 / (Sözen and Özaydin 2010)
Feminasia balearicaa / Endemic / 7 / Shrub, enthomophilous outcrosser, siliceous costal cliff, deciduous pappus. / 2x / AFLP / 0.237/0.157-0.190 / (Vilatersana et al. 2007)
C. cineraria / Endemic / 2 / Perennial, limestone cliff. / 2x / Allozymes / No data/0.126-0.186 / (Bancheva 2006)
C. ucriae / Endemic / 3 / Limestone cliff. / 2x / Allozymes / No data/0.130-0.205 / (Bancheva 2006)
C. todari / Endemic / 2 / Limestone cliff. / 2x / Allozymes / No data/0.226-0.276 / (Bancheva 2006)
C. tenorei / Endemic / 3 / Perennial herb. / 2x-4x / Allozymes / 0.08/No data / (Palermo 2002)
C. parlatoris / Endemic / 3 / Perennial herb. / 2x / Allozymes / 0.34/No data / (Palermo 2002)
C. maculosa spp. maculosa / Widespread / 5 / Perennial, self-incompatible, enthomophilous, monocarpic, calcareous rocky places. / 2x / Allozymes / No data/0.044-0.170 / (Fréville et al. 1998)
C. solstitialis / Widespread / 22 / Annual. Alien range (North America, since 1800). / 2x / Allozymes / No data/0.257-0.417 / (Sun 1997)
C. jacea / Widespread / 5 / Perennial, enthomophilous, self-incompatible, fruit with pappus. / 2x / Allozymes / No data/0.27-0.45 / (Hardy and Vekemans 2001)
5 / 4x / No data/0.36-0.41
C. diffusa / Widespread / 8 / Outcrosser. Alien range (North America, since 1907). / 2x / Microsatellites / No data/0.436-0.692 / (Marrs et al. 2008b)
5 / Outcrosser. Native range (Eurasia). / 2x-4x / Microsatellites / No data/0.311-0.592
C. stoebe spp. micranthos / Widespread / 11 / Alien range (North America). / 4x / Microsatellites / No data/0.616-0.809 / (Marrs et al. 2008a)
15 / Native range (Eurasia). / 4x / Microsatellites / No data/0.521-0.856
C. africana / Widespread / 1 / Perennial, / 2n=30b / Allozymes / 0.35/0.35 / (Garnatje et al. 1998)

a Formerly known as Centaurea balearica J.J. Rodr. b Ploidy not indicated.

REFERENCES

Bancheva SG, A. & Raimondo, F. M. (2006) Genetic diversity in the Centaurea cineraria group (Compositae) in Sicily using isozymes. Plant Biosystems- An International Journal Dealing with all Aspects of Plant Biology 140: 10-16

Colas B, Olivieri I, Riba M (1997) Centaurea corymbosa, a cliff-dwelling species tottering on the brink of extinction: A demographic and genetic study. Proc Natl Acad Sci USA94: 3471-3476

Fréville H, Colas B, Ronfort J, Riba M, Olivieri I (1998) Predicting endemism from population structure of a widespread species: Case study in Centaurea maculosa Lam. (Asteraceae). ConservBiol12: 1269-1278

Fréville H, Justy F, Olivieri I (2001) Comparative allozyme and microsatellite population structure in a narrow endemic plant species, Centaurea corymbosa Pourret (Asteraceae). Mol Ecol 10: 879-889

Garnatje T, Susanna A, Messeguer R (1998) Isozyme studies in the genus Cheirolophus (Asteraceae : Cardueae-Centaureinae) in the Iberian Peninsula, North Africa and the Canary Islands. Plant Syst Evol 213: 57-70

Hardy OJ, Vekemans X (2001) Patterns of allozyme variation in diploid and tetraploid Centaurea jacea at different spatial scales. Evolution 55: 943-954

Mameli G, Filigheddu R, Binelli G, Meloni M (2008) The genetic structure of the remnant populations of Centaurea horrida in Sardinia and associated islands. Ann Bot 101: 633-640

Marrs RA, Sforza R, Hufbauer RA (2008a) Evidence for multiple introductions of Centaurea stoebe micranthos (spotted knapweed, Asteraceae) to North America. Mol Ecol 17: 4197-4208

Marrs RA, Sforza R, Hufbauer RA (2008b) When invasion increases population genetic structure: a study with Centaurea diffusa. BiolInvasions 10: 561-572

Palermo AMP, G.; Musacchio, A. & menale, B. (2002) Allozymic variability in Centaurea tenorei Guss. ex Lacaita and in other species of C. parlatoris Heldr. group (Asteraceae). Plant Biosystems- An International Journal Dealing with all Aspects of Plant Biology 136: 331-337

Sözen E, Özaydin B (2009) A preliminary study of the genetic diversity of the critically endangered Centaurea nivea (Asteraceae). Ann Bot Fenn 46: 541-548

Sözen E, Özaydin B (2010) A Study of Genetic Variation in Endemic Plant Centaurea wiedemanniana by Using RAPD Markers. Ekoloji 19: 1-8

Sun M (1997) Population genetic structure of yellow starthistle (Centaurea solstitialis), a colonizing weed in the western United States. Can J Bot-Rev Can Bot 75: 1470-1478

Vilatersana R, Susanna A, Brochmann C (2007) Genetic variation in Femeniasia (Compositae, Cardueae), an endemic and endangered monotypic genus from the Balearic Islands (Spain). Bot J Linn Soc 153: 97-107