Tragopogon

Tragopogon L.

Tragopogon is a very complex genus of ca. 150 species (only 50 according to Matthews 2000), predominantly distributed in Eurasia and the Mediterranean area. Two allotetraploids derived from T. dubius are native to the United States (Ownbey 1950, Novak & al. 1991, Soltis 2006). One variable species, T. pratensis, is native in Belgium (Lambinon & Verloove 2012). Some of the widespread European species (e.g. T. dubius, T. pratensis, T. porrifolius, T. orientalis) may be non-monophyletic, comprising several distinct lineages and possibly unnamed “cryptic species” (Mavrodiev & al. 2012). Further molecular studies will probably shed new light on species boundaries within Tragopogon. Carpological studies also seem to be promising (e.g. Blanca & Díaz de la Guardia 1997, Sukhorukov & Nilova 2015). The present account is in accordance with traditional taxonomy of the genus and surely merely provisional.

The infraspecific variability and taxonomy of Tragopogon pratensis is still insufficiently known. The taxon usually called subsp. orientalis (L.) Čelak. (syn.: T. orientalis L.), distinguished by golden yellow ligules and achenes with a beak shorter than the body (see also Lambinon & Verloove 2012), is best accepted as a distinct species, as shown by molecular data (Mavrodiev & al. 2004; also Mavrodiev & al. 2012, Sukhorukov & Nilova 2015). Its residence status in Belgium is unknown. It was already known in the 19th century (e.g. Durand 1899) but possibly is not native. According to Regel (1955) it is the eastern and northeastern counterpart of T. pratensis. Recent records are from highly artificial habitats and also rather suggest non-native status. In Merelbeke, near to Ghent, for instance, this taxon was seen as an escape from a wild flower seed mixture in 2014.

The lectotypification of several widespread species of Tragopogon, incl. T. pratensis, by Díaz de la Guardia & Blanca (1992) may further complicate the issue. Their lectotype of the latter has five involucral bracts while plants usually seen in western Europe have ca. 7-8 bracts (see also Tison & de Foucault 2014).

Some plants are more or less intermediate between native Tragopogon pratensis and non-native T. dubius and might represent their F1-hybrid (T. xcrantzii Dichlt.). An allotetraploid, resulting from repeated crossings between both species, is known as Tragopogon miscellus Ownbey but apparently does not occur (yet) in Europe (Soltis 2006). It is similar to T. pratensis but larger and more robust.

In general, hybrids between species of Tragopogon are only exceptionally produced and are therefore not included in the key beneath. The only hybrid that has been reliably recorded (Tragopogon xmirabilis) is discussed under T. porrifolius.

Additional information on Tragopogon is available at Soltis lab at: http://www.flmnh.ufl.edu/soltislab/trags/


1       Ligules entirely purple === Tragopogon porrifolius

         Ligules yellow (rarely golden to orange) === 2

2       Peduncles distinctly inflated below the head, up to 10 mm wide. Achenes 25-35 mm long (incl. beak) === T. dubius

         Peduncles not or only slightly inflated below the head. Achenes 10-25 mm long (incl. beak) (native) === T. pratensis

Literature:


Blanca G. & Díaz de la Guardia C. (1996) Sinopsis del género Tragopogon L. (Asteraceae), en la Península Iberica. Anales Jard. Bot. Madrid 54: 358-363. [available online at: http://dialnet.unirioja.es/servlet/articulo?codigo=70447]

Blanca G. & Díaz de la Guardia C. (1997) Fruit morphology in Tragopogon L. (Compositae: Lactuceae) from the Iberian Peninsula. Bot. J. Linn. Soc. 125(4): 319-329. [available online at: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.378.2277&rep=rep1&type=pdf]

Bobowicz M.A. (1984) Species variability in Tragopogon L. genus (Asteraceae) in Poland. 1. Interspecific variability of Tragopogon dubius Scop., Tragopogon pratensis L., Tragopogon orientalis L., Tragopogon heterospermus (Schweigg.) C. Rgl. and Tragopogon porrifolius L. Bull. Soc. Amis Sci. Lett. Poznań, ser. D – biol. 24: 109-121.

Clausen J. (1966) Stability of genetic characters in Tragopogon species through 200 years. Trans. & Proc. Bot. Soc. Edinburgh 40: 148-158.

Clements D.R., Upadhyaya M.K. & Bos S.J. (1999) The biology of Canadian weeds: 110. Tragopogon dubius Scop., Tragopogon pratensis L. and Tragopogon porrifolius L. Canad. J. Pl. Sci. 79: 153-163. [available online at: http://pubs.aic.ca/doi/pdf/10.4141/P98-007]

Díaz de la Guardia C. & Blanca G. (1992) Lectotypification of five Linnean species of Tragopogon L. (Compositae). Taxon 41: 548-551.

Durand T. (1899) Phanérogames. In: De Wildeman E. & Durand T., Prodrome de la flore belge. A. Castaigne Editeur, Bruxelles: 1112 p.

Dvořák F. (1976) Cytotaxonomic study of Tragopogon L. in Czechoslovakia. Folia Geobot. Phytotax. 13: 305-330.

Lambinon J. & Verloove F. (avec coll. Delvosalle L., Toussaint B., Geerinck D., Hoste I., Van Rossum F., Cornier B., Schumacker R., Vanderpoorten A. & Vannerom H.) (2012) Nouvelle Flore de la Belgique, du Grand-Duché de Luxembourg, du Nord de la France et des Régions voisines (Ptéridophytes et Spermatophytes). Sixième édition. Jardin botanique national de Belgique, Meise: CXXXIX + 1195 p.

Matthews V.A. (2000) Tragopogon. In: Cullen J. & al. (eds.), The European Garden Flora, vol. 6. Cambridge University Press, Cambridge: 545.

Mavrodiev E.V., Gitzendanner M., Calaminus A.K., Baldini R.M., Soltis P.S. & Soltis D.E. (2012) Molecular phylogeny of Tragopogon L. (Asteraceae) based on seven nuclear loci (Adh, GapC, LFY, AP3, PI, ITS, and ETS). Webbia 67(2): 111-137. [available online at: https://www.researchgate.net/publication/271568580_Molecular_phylogeny_of_Tragopogon_L._%28Asteraceae%29_based_on_seven_nuclear_loci_%28_Adh_GapC_LFY_AP3_PI_ITS__and_ETS%29]

Mavrodiev E.V., Krahulec F., Soltis D.E. & Soltis P.S. (2013) A cryptic taxon rather than a hybrid species of Tragopogon (Asteraceae) from the Czech Republic. Kew Bull. 68(1): 1-9. [available online at: https://www.researchgate.net/publication/257776517_A_cryptic_taxon_rather_than_a_hybrid_species_of_Tragopogon_%28Asteraceae%29_from_the_Czech_Republic]

Mavrodiev E.V., Soltis D.E. & Alexeev Y.E. (2004) Diagnostics of Tragopogon x crantzii Dichtl (T. dubius Scop. x T. Orientalis L.), a new nothospecies for Russian flora, and taxonomic independence of T. orientalis L.: evidence from the ITS sequence data (in Russian). Byull. Mosk. Obshch. Ispyt. Prir., Biol. 109: 83-87.

Mavrodiev E.V., Tancig M., Sherwood A.M., Gitzendanner M.A., Rocca J., Soltis P.S. & Soltis D.E. (2005) Phylogeny of Tragopogon L. (Asteraceae) based on internal and external transcribed spacer sequence data. Int. J. Pl. Sci. 166: 117-133.

Novak S.J., Soltis D.E. & Soltis P.S. (1991) Ownbey’s tragopogons: Forty years later. Amer. J. Bot. 78: 1586-1600.

Ownbey M. (1950) Natural hybridization and amphiploidy in the genus Tragopogon. Amer. J. Bot. 37: 487-499.

Regel C. (1955) Die Verbreitung einiger europäisch-asiatischer Tragopogon-Arten. Gesellschaft Berichte der Schweizerischen Botanischen 65: 251-262.

Richardson I.B.K. (1976) Tragopogon. In: Tutin T.G. & al. (eds.), Flora Europaea, vol. 4. Cambridge University Press, Cambridge: 322-325.

Soltis P.S. (2006) Tragopogon. In: Flora of North America Editorial Committee (eds.), Flora of North America, vol. 19. Oxford University Press, New York-Oxford: 303-306. [available online at: http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=133279]

Sukhorukov A. & Nilova M.V. (2015) Carpology of the genus Tragopogon L. (Asteraceae). Phytotaxa 201(1): 27-49. [available online at: http://www.mapress.com/phytotaxa/content/2015/f/p00201p049f.pdf]

Tison J.-M. & de Foucault B. (coord.) 2014) Flora Gallica. Flore de France. Editions Biotope, Mèze : xx + 1196 p.

Taxonomic name: 
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith