Knapweeds (Centaurea L. and some related genera) in North America

© Jörg Ochsmann 2006

(last updated: 29.01.2007)


The following knapweed species are listed for North America. Neophythes are marked with (N).

Note: This page is currently under revision, major changes may occur.


Plant List References Taxonomic Information

Plant List


References / Literatur

  • Britton, N.L. & Brown, A. (Eds.) 1913: An illustrated flora of the Northern United States, Canada and the British possesions. (2nd ed.). 3: 556-560.
  • Clement, E.J. & Foster, M.C. 1994: Alien plants of the British Isles. B.S.B.I., London, 590 pp.
  • Hickman, J.C. (Ed.) 1993: The Jepson Manual: higher plants of California. University of California Press, 1400 pp.
  • Maddox, D.M. 1979: The knapweeds: their economics and biological control in the western states, U.S.A. - Rangelands 1: 139-141.
  • Newmaster, S.G., Lehela, A., Uhlig, P.W.C., McMurray, S. & Oldham, M.J. 1998: Ontario plant list. - Forest Res. Inf. Paper 123.
  • Keil, D.J. & Ochsmann, J. 2006: Centaurea L. In: Flora of North America [online version]
  • Ochsmann, J. 2000: Morphologische und molekularsystematische Untersuchungen an der Centaurea stoebe L.-Gruppe (Asteraceae-Cardueae) in Europa. - Diss. Bot. 324: 242 pp.
  • Roché, B.F., Piper, G.L. & Talbott, C.J. 1986: Knapweeds of Washington. U.S. Dept. of Agriculture, Washington, 41 pp.
  • Roché, C.T. & Roché, B.F. Jr 1989: Introductory notes on squarrose knapweed (Centaurea virgata Lam. ssp. squarrosa Gugl.). - Northwest Sci. 63(5): 246-252.
  • Roché, C.T. & Roché, B.F. Jr 1991: Meadow Knapweed invasion in the Pacific Northwest, U.S.A. and British Columbia, Canada. - Northwest Sci. 65: 53-61.
  • Wagenitz, G. (Ed.) 1987: Gustav Hegi. Illustrierte Flora von Mitteleuropa. (2. Ed.) VI/4. Parey, Berlin, 1483 pp.
  • Wagenitz, G. & Hellwig, F.H. 1996: Evolution of characters and phylogeny of the Centaureinae. In: Hind, D.J.N. & Beentje, H.J. (Eds.): Compositae: Systematics. Proceedings of the International Compositae Conference, Kew, 1994. Kew, 491-510.
  • Yatskievych, G. & Turner, J. 1990: Catalogue of the flora of Missouri. - Monogr. Syst. Bot. 37: 345 pp.

Taxonomic Information

Acroptilon Cass. (1827) in Dict. Sci. Nat. 1: 464.


Acroptilon repens (L.) DC. (1838) Prodr. 6: 663.
Typus: "Carduus orientalis caicitrapae folio, flore minimo. tournef. cor. 31", P-LAM (holo-)
Synonyms / Synonyme:
Basionym: Centaurea repens L. (1763) Sp. pl. (ed. 2): 1293.
= Centaurea picris PALL. ex WILLD. (1803) Sp. pl. 3(3): 2302.
    = Acroptilon picris (PALL. ex WILLD.) C.A. MEY. (1831) Verz. Pfl. Cauc.: 67.
incl. Acroptilon australe ILJIN (1937) in Not. Syst. Herb. Inst. Bot. Acad. Sci. URSS 7: 59.
    = Acroptilon alpinum subsp. australe (ILJIN) RECH.f. (1980) Fl. Iran. 139b: 309.
Chromosome no. / Chromosomenzahl (2n): 26
Distribution / Verbreitung:
Common Names / Volksnamen: E. creeping knapweed, hardheads, hardhead thistle, Russian knapweed, Turkestan thistle G. Federblume; Swed. hinnklint
Images / Bilder: Acroptilon_repens_02_stamp.jpg (1150 Byte)  Acroptilon_repens_01_stamp.jpg (994 Byte)
Biological control / Biologische Bekämpfung: (Lethbridge Research Centre Biology of Target Weeds): Puccinia acroptili (rust desease /Rostpilz), Subanguina picridis (gall nematode/ Gall-Nematode)
References / Literatur:
  • McIlroy, D.A & Faithfull, I. 1998: Hardheads/Russian knapweed. - Landcare Notes PP0045
  • Watson, A.K. 1980: The biology of Canadian weeds, 43. Acroptilon (Centaurea) repens (L.) DC. - Canad. J. Pl. Sci. 60: 993-1004.
  • Wagenitz, G. 1987: Centaurea. in: Hegi, G., Illustrierte Flora von Mitteleuropa VI/2 (2. Aufl.): Nachträge, Berichtigungen und Ergänzungen zum Nachdruck der 1. Aufl. von Band VI/2 (1928/9). 1405-1413. Berlin.
  • Weinert, E. & Breitkopf, H. 1967: Acroptilon repens (L.) DC., ein Neophyt in Mitteldeutschland. - Hercynia, N.F. 4: 146-151.
Notes / Bemerkungen: Based on achene characters this species should not be included in Centaurea (see Wagenitz 1987). Information on the biology are presented by Watson 1980). Distribution data for Germany are given in Weinert & Breitkopf 1967).
(last updated: 29.01.2007)

Amberboa (Pers.) Less. (1832) Syn. Comp. 8.


Amberboa moschata (L.) DC. (1838) Prodr. 6: 560.
    = Centaurea moschata L. (1753) Sp. pl.: 909.
    Common names: E. Sweet-sultan

    Native to SW Asia. A casual garden escape on the British Isles.


Centaurea L. (1753) Sp. pl.: 909.
    Typus: Centaurea centaurium L.
    incl. Cnicus L. (1753) Sp. pl.
    = Cyanus Mill. (1754) Gard. Dict. Abr., ed. 4: [422].
    = Jacea Mill. (1754) Gard. Dict. Abr., ed. 4: [663].
    = Calcitrapa Heist. ex FABR. (1759) Enum.: 94.
    = Acosta Adans. (1763) Farn. pl. 2: 117, 512.
    = Acrolophus Cass. (1827) Dict. Sci. Nat. 1: 253.
    = Bielzia Schur (1866) Enum. Pl. Transsilv. 409.


Centaurea aspera L. (1753) Sp. pl.: 916.
Chromosome no. / Chromosomenzahl (2n): 22 (Guinochet 1957; Hellwig 1994), 44 (Humphries et al. 1978)
Life form / Lebensform: polycarpic perennial
Distribution / Verbreitung: 
  •  Native to S Europe, N Africa; introduced into N America.
Habitat: Waste places, rocks and sandy places near the sea, 0-300 m.s.m.
Common Names / Volksnamen: E. rough star-thistle; It. fiordaliso ispido; Swed. raspklint
Images / Bilder:  (Scanned from herbarium specimens.)
References / Literatur:
  • GUINOCHET, M. 1957: Contribution à l'étude caryologique dur genre Centaurea L. sensu lat. - Bull. Soc. Hist. Nat. Afrique N. 48: 282-300.
  • HELLWIG, F.H. 1994: Chromosomenzahlen aus der Tribus Cardueae (Compositae). - Willdenowia 24: 219-248.
  • HUMPHRIES, C.J., MURRAY, B.G. et al. 1978: Chromosome numbers of phanerogams from Morocco and Algeria. - Bot. Notis. 131: 391-406.
(last updated: 29.01.2007)

Centaurea benedicta (L.) L. (1763) Sp. pl. (ed. 2): 1296.
    = Cnicus benedictus L. (1753) Sp. pl.: 826.
    = Cirsium pugnax
Sommier & Levier 
   
Common names / Volksnamen: E. blessed-thistle; F. chardon bénit; It. Cardo benedetto

    Chromosome no. / Chromosomenzahl (2n): 22 (Moore & Frankton 1962, Canad. J. Bot. 40: 284)

    Distribution: Native in the Mediterranean.

    Note: According to molecular evidence this taxon has to be included in Centaurea s.str..


Centaurea bovina Velen. (1890) Sitz.-Ber. Boehm. Ges. Wiss. 1889 (II): 36.
    Typus: Bornmüller: Bulgaria, pr. Varna (B?)


Centaurea calcitrapa L. (1753) Sp. pl.: 917.
   
= Calcitrapa stellata LAM. (1779) Fl. franç. 2: 34, nom. illeg.
   Common names: E. star-thistle, red star-thistle, purple star-thistle; F. (centaurée) chausse-trapé; G. Stern-Flockenblume
   Distribution map for NW America from Invaders Database System


??? Centaurea calcitrapoides 

Note: Clement & Foster (1994) list C. calcitrapoides L. as in error for C. ×pouzinii; this may also be true for North America. The Index Kewensis list four homonyms for C. calcitrapoides that refer to different taxa: 

Author Taxon
L., Cent 1: 29  
DC., Prodr. 6: 597 ?-> C. iberica
Gouan (1764) Fl. Monsp. 461. ?-> C. ×pouzinii
Thuill. Fl. Par.: 466. ?-> C. calcitrapa
  
References:
  • Clement, E.J. & Foster, M.C. 1994: Alien plants of the British Isles. B.S.B.I., London, 590 pp.
  • Index Kewensis CD-ROM, 2nd ed.

Tafel_595_01_Stamp.jpg (8046 Byte) Centaurea cyanus L. (1753) Sp. pl.: 911.
    = Cyanus segetum HILL (1769) Herb. Brit. 1: 82.
    = Centaurea pulchra DC. (1837) Prodr. 6: 578.
   Common names: E. corn flower, cornflower, blue-bottle, bachelor's button; F. bluet,
centaurée bleue; G. Kornblume; It. fiordaliso; Russ. vasiljok sinij, vasiljok posevnoj

Centaurea diffusa LAM. (1785) Encycl. 1: 675.
Typus: "Carduus orientalis caicitrapae folio, flore minimo. tournef. cor. 31", P-LAM (holo-)
Synonyms / Synonyme:
= Acrolophus diffusus (LAM.) Á. LÖVE & D. LÖVE (1961) in Bot. Not. 114: 44.
= Acosta diffusa SOJÁK (1972) in Cas. Nár. Muz., Odd. Prír. 140: 134.
Chromosome no. / Chromosomenzahl (2n): 18, 36 (Georgiadis & Phitos 1976, Kuzmanov et al. 1981, Moore & Frankton 1954, Powell et al. 1974, Taylor & Taylor 1977, Tonjan 1968, Uhrikova & Májovský 1977 u. 1978, Kuzmanov et al. 1979 u. 1981, Van Loon & De Jong 1978, Ochsmann 1999)
Life form / Lebensform: (annual to) biennual, monocarpic
Distribution / Verbreitung:
Common Names / Volksnamen: E. diffuse knapweed, tumble-knapweed, white knapweed; F. centaurée diffuse; G. Sparrige Flockenblume; It. Fiordaliso diffuso; Swed. spretklint
Images / Bilder: Centaurea_diffusa_01_Stamp.jpg (1902 Byte)
  • Hayek (1901: tab. VIII, fig. 7)
  • Prodan (1930: tab. IV, fig. 10 et tab. XXXIII)
  • Prodan & Nyárády (1964: 841, tab. 170, fig. 2)
  • Watson & Renney (1974: 688)
Molecular data / molekulare Daten: ITS 1 (EMBL database): AJ402890; IGS (EMBL database): AJ405093, AJ405124
Herbivores / Schadinsekten: (Cornell Univ., Biological Control): Agapeta zoegana, Cyphocleonus achates, Pterolonche inspersa, Sphenoptera jugoslavica, Urophora affinis
References / Literatur:
  • Callaway, R.M. & Aschehoug, E.T. 2000: Invasive plants versus their new and old neighbors: A mechanism for exotic invasion. - Science 290: 521-523.
  • Campobasso, G. Sobhian, R., Knutson, L., Pastorino, A.C. & Dunn, P.H. 1994: Biology of Pterolonche inspersa (Lep.: Pterolonchidae), a biological control agent for Centaurea diffusa and C. maculosa in the United States. - Entomophaga 39(3-4): 377-384.
  • Harris, P. 1980: Effects of Urophora affinis Frfld. and U. quadrifasciata (Meig.) (Diptera: Tephritidae) on Centaurea diffusa Lam. and C. maculosa Lam. - Z. Angew. Entomol. 90: 190-201.
  • Harris, P. & Cranston, R. 1979: An economic evaluation of control methods for diffuse and spotted knapweed in western Canada. - Canad. J. Pl. Sci. 59: 375-382.
  • Harrod, R.J. & Taylor, R.J. 1995: Reproduction and pollination biology of Centaurea and Acroptilon species, with emphasis on C. diffusa. - Northwest Sci. 69(2): 97-105.
  • Maddox, D.M. 1982: Biological control of diffuse knapweed (Centaurea diffusa) and spotted knapweed (C. maculosa). - Weed Sci. 30: 76-82.Myers, J.H. & Berube, D.E. 1983: Diffuse knapweed invasion into rangeland in the dry interior of British Columbia. - Canad. J. Pl. Sci. 63: 981-987.
  • Popova, A.Y. 1960: [Centaurea diffusa LAM., a steppe-pasture weed in the Crimea.] - Bot. Zhurn. (Moscow & Leningrad) 45: 1207-1213. [in Russian]
  • Powell, R.D. 1990: The role of spatial pattern in the population biology of Centaurea diffusa. - J. Ecol. 78(2): 374-388.
  • Powell, R.D. and Myers, J.H. (1988) The effect of Sphenoptera jugoslavica Obenb. (Col., Burprestidae) on its host plant Centaurea diffusa Lam. (Compositae). J. Appl. Ent. 106: 25-45.
  • Schirman, R. 1981: Seed production and spring seedling establishment of diffuse and spotted knapweed. - J. Range Managem. 34(1): 45-47.Sheley, R.L., Jacobs, J.S. & Carpinelli, M.F. 1998: Distribution, Biology, and Management of Diffuse Knapweed (Centaurea diffusa) and Spotted Knapweed (Centaurea maculosa). - Weed Technol. 12(2): 353-362.
  • Thompson, D.J. & Stout, D.G. 1990: Duration of the juvenile period in diffusa knapweed (Centaurea diffusa). - Canad. J. Bot. 69: 368-371.
  • Watson, A.K. & Renney, A.J. 1974: The biology of Canadian weeds. 6. Centaurea diffusa and C. maculosa. - Canad. J. Pl. Sci. 54: 687-701.
  • Zimmerman, J.A.C. 1997: Ecology and distribution of Centaurea diffusa LAM., Asteraceae. U.S. Geological Service- Biological Resources Division Colorado Plateau Research Station - Flagstaff, Arizona, Flagstaff, Arizona. [http://www.usgs.nau.edu/swemp/Info_pages/plants/Centaurea_diffusa/diffusa.html]
  • Zwölfer, H. (1976) Investigations on Sphenoptera (Chilostetha) jugoslavica Obenb. (Col., Buprestidae), a possible biocontrol agent of the weed Centaurea diffusa Lam. (Compositae) in Canada. Z. ang. Ent. 80:170-190.
Remarks / Anmerkungen: Die Sippe tritt in Deutschland verwildert auf Bahnanlagen, in Häfen und anderen Ruderalstandorten in der Nähe von Verkehrswegen auf, wo sie stabile Populationen aufbaut. Sie ist offenbar in Ausbreitung begriffen. Wenn die Art zusammen mit C stoebe vorkommt, kann es zu spontaner Bastardierung kommen (vgl. RECHINGER, 1950; SCHABERG, 1965; HERDAM et al., 1993).
(last updated: 29.01.2007)

Centaurea diluta Aiton (1789) Hort. Kew. ed.1. 3: 261.
    Common names: E. lesser star-thistle


Centaurea iberica Trev. ex Spreng. (1826) Syst. Veg. 3: 406.
    = Calcitrapa iberica (Spreng.) Schur (1866) Enum. Pl. Transs. 409.
    = Leucantha iberica (Spreng.) Á. Löve & D. Löve (1961) in Bot. Notis. 114: 44.
    Distribution map for NW America from Invaders Database System


Centaurea jacea L. (1753) Sp. pl.: 914, s.l.
Typus: Herb. Linn. No. 1030.36, LINN (lecto- MARSDEN-JONES & TURRILL 1954: British Knapweeds, London: 14, t.2)
Synonyms / Synonyme:
    = Jacea pratensis LAM. (1778) Fl. Franc. 2: 55.
    = Centaurea decipiens THUILL. (1799) Fl. Env. Paris, ed. 2: 445.
        = Centaurea jacea subsp. decipiens (THUILL.) CELAK. (1871) Prodr. Fl. Böhmen 2: 250.
        = Centaurea amara subsp. decipiens (THUILL.) ARÈNES (1948) Bull. Soc. Franc. Ech. Pl. Vase. 1948: 40.
    = Centaurea pratensis THUILL. (1799) Fl. Env. Paris, ed. 2: 444 non SALISB. (1796) nom. illeg.
    = Cyanus jacea (L.) P. GAERTN., B. MEY. & SCHERB. (1801) Oekonom.-Techn. Fl. Wetterau 3(1): 172.
    = Centaurea jacea subsp. pratensis CELAK. (1871) Prodr. Fl. Böhmen 2: 250.
    = Centaurea subjacea (BECK) HAYEK (1901) Akad. Wiss. Wien, Math.-Naturwiss. Kl., Denkschr. 70: 712.
        = Centaurea jacea subsp. subjacea (BECK) HYL. (1945) Uppsala Univ. Arsskr. 1945(7): 322.
    = Centaurea debeauxii subsp. thuillieri DOSTÁL (1976) Bot. J. Linn. Soc. 71: 207.
       
= Centaurea thuillieri (DOSTÁL) J. DUVIGN. & LAMBINON (1978) Nouv. Fl. Belg. Lux. Nord-France, ed. 2: 829.

   
= Centaurea decipiens var. (?) subjacea BECK (1893) Fl. Nieder-Österr. 2(2): 1263.
    
Chromosome no. / Chromosomenzahl (2n): 22, 44
Life form / Lebensform: perennial
Distribution / Verbreitung:
Common Names / Volksnamen: E. brown knapweed, rayed knapweed; F. (centaurée) jacée; G. Wiesen-Flockenblume; SF. ahdekaunokki; Swed. rödklint
Images / Bilder: Tafel_594_01_Stamp.jpg (9206 Byte)
References / Literatur:
  • Wagenitz, G. (Ed.) 1987: Gustav Hegi. Illustrierte Flora von Mitteleuropa. (2. Ed.) VI/4. Parey, Berlin, 1483 pp. 

Remarks:
The illegitimate name C. pratensis Thuill. refers to a dubious, ill-defined taxon of presumably hybrid origin (see Wagenitz (1987: 1409) that is also treated as Centaurea thuillieri, Centaurea debeauxii subsp. thuillieri, and as subspecies of C. nigra. The name C. pratensis is also used for spontaneous hybrids between C. jacea and C. nigra (C. ×moncktonii C.E. Britton) by the Invaders Database System.

 

Anmerkungen:
Der illegitime Name C. pratensis Thuill. bezieht sich auf eine zweifelhafte, schlecht definierte Sippe mit möglicherweise hybridogenem Ursprung (vgl. Wagenitz (1987: 1409). Diese wird auch als Centaurea thuillieri, Centaurea debeauxii subsp. thuillieri und als Unterart von C. nigra bezeichnet. Der Name C. pratensis wird vom Invaders Database System auch für spontane Hybriden zwischen C. jacea und C. nigra (C. ×moncktonii C.E. Britton) verwendet.
Die Bearbeitung in Haeupler & Muer (2000) mit einer Aufspaltung in eine Vielzahl von Kleinarten entspricht nicht der Auffassung des Autors und ist aufgrund der sehr hohen Variabilität der Pflanzen nicht haltbar. Bei den dort publizierten neuen Namen handelt es sich um nomina nuda!

(last updated: 29.01.2007)

Centaurea macrocephala Muss. Puschk. ex Willd. (1803) Spec. Pl. 3(3): 2298.
    = Phaeopappus macrocephalus (Willd.) Boiss. (1846) Diagn. Pl. Or. ser. I. 6: 124.
    = Grossheimia macrocephala (Willd.) Sosn.& Takht. (1945) Dokl. Akad. Nauk Armyan. SSR 2: 23.
    Common names: E. bighead knapweed; Swed. gulklint
    Distribution map for NW America from Invaders Database System


Centaurea melitensis L. (1753) Sp. pl.: 917.
    = Triplocentron melitense (L.) Cass. (1828) in Dict. Sci. Nat. 55: 349.
    = Calcitrapa melitensis (L.) Soják (1972) in Cas. Nár. Muz., Odd. Prir. 140: 133.

    Common names: E. Maltese star-thistle; F. coix de Malte; Swed. maltaklint
    Distribution map for NW America from Invaders Database System


Centaurea ×moncktonii C.E. Britton (1921) in Rep. Bot. Exch. Cl. Brit. Isles 1920(6): 172.
    [Centaurea jacea L. × Centaurea nigra L.]
    = Centaurea ×drucei C.E. Britton (1921) in Rep. Bot. Exch. Cl. Brit. Isles 1920(6): 410.
    Distribution map for NW America from Invaders Database System

Named after H.W. Monckton (1857-1931).
Note: The Index Kewensis (CD-ROM ed. 2) gives a wrong spelling of the name ("monktonii").

References:
  • Stace, C.A. 1991: New Flora of the British Isles. Cambridge, 1226 pp. [see p. 815 for description]

Centaurea montana L. (1753) Sp. pl. (1753) 911.
    = Cyanus montanus (L) HILL (1768) Hort. Kew.: 64.
    Common names: E. montane knapweed, perennial corn flower; F. centaurée de montagne; G. Berg-Flockenblume;
                                   Swed. bergklint


Centaurea nigra L. (1753) Sp. pl.: 911, s.l.
Typus: Herb. Linn. No. 1030.13. LINN (lecto- Marsden-Jones & Turrill 1954: British Knapweeds, London: 13, t.4)
Synonyms / Synonyme:
= Jacea nigra (L.) HILL (1769) Herb. Brit. 1: 83.
= Centaurea nigra agg.
Chromosome no. / Chromosomenzahl (2n): 22, 44
Life form / Lebensform: perennial
Distribution / Verbreitung:
Common Names / Volksnamen: E. black knapweed, common knapweed, horse-knops, hardheads, centaury, Spanish buttons; F. centaurée noire; G. Schwarze Flockenblume G. Schwarze Flockenblume; Swed. svartklint
Images / Bilder: Centaurea_nigra_ssp_nigra_01_stamp.jpg (5710 Byte) Centaurea_nigra_ssp_nemoralis_01_stamp.jpg (5824 Byte) Centaurea_nigra_ssp_nemoralis_02_stamp.jpg (6157 Byte)
(last updated: 29.01.2007)

Centaurea nigrescens WILLD. (1803) Sp. pl. 3(3): 2288.
    = Jacea nigrescens (WILLD.) SOJÁK (1972) Cas. Nár. Mus., Odd. Prir. 140: 132.
    = Centaurea dubia subsp. nigrescens (WILLD.) HAYEK (1918) Verh. Zool.-Bot. Ges. Wien 68: 210.
    Common names: E. blackish knapweed, Tyrol knapweed; Swed. fjunklint
    Distribution map for NW America from Invaders Database System


Centaurea ×pouzinii DC. (1813) Cat. Pl. Horti Monsp.: 91.
[Centaurea calcitrapa L. × Centaurea aspera L.]
    ? Centaurea ×calcitrapoides Gouan (1764) Fl. Monsp. 461.
    = Centaurea ×aspero-calcitrapa Godr. & Gren. in Gren. & Godr. (1850) Fl. Fr. 2: 260.
    = Centaurea ×calcitrapo-aspera Godr. & Gren. in Gren. & Godr. (1850) Fl. Fr. 2: 260.


Centaurea ×psammogena GÁYER (1909) in Magyar. Bot. Lapok. 8: 61.
(= C. diffusa LAM. s.l. × C. stoebe L. s.l.)
Typus: "Bánhida, loco arenoso ad viam ferram versus Kis-Bér ducentem, 09.09.1908, Gáyer, G" (BP)
Synonyms / Synonyme:
    = Acosta ×psammogena (GÁYER) HOLUB (1972) in Folia Geobot. Phytotax. 7: 314.
= Centaurea ×zimmermanniana ZINSM. (1916) in Mitt. Bayer. Bot. Ges. 3: 282.
Chromosome no. / Chromosomenzahl (2n): 18 (Ochsmann 1998)
Life form / Lebensform: annual to biennual
Distribution / Verbreitung:
  • Europe: A, B, D, F, H, I, LV, PL, RO, UA; N America: USA, CAN [data based on herbarium specimens seen by the author]
Images / Bilder: Centaurea_x_psammogena_01_Stamp.jpg (4372 Byte)
References / Literatur:
  • Galenieks, P. (Ed.) 1959: Latvijas PSP Flora. 4: 522.
  • Gáyer, G. 1909: Vier neue Centaureen der Flora von Ungarn. - Magyar Bot. Lapok 8: 58-61.
  • Hayek, A. v. 1921: Über Centaurea Zimmermanniana Zinsm. - Mitt. Bayer. Bot. Ges. 3(30): 527-528.
  • John, H. & Zenker, E. 1996: Funde und Beobachtungen von höheren Pflanzen im südlichen Sachsen-Anhalt. - Mitt. florist. Kart. Sachsen-Anhalt 1: 49-57.
  • Kornas, J., Lesniowska, I. & Skrzywanek, A. 1959: Obserwacje nad flora linii kolejowych i dworców towarowych w Krakowie - Bemerkungen über die Flora der Eisenbahnlinien und Güterbahnhöfe in Kraków. - Fragm. Florist. Geobot. 5(2): 199-216.
  • Melzer, H. & Barta, T. 2001: Cotula coronopifolia, die Laugenblume, neu für Österreich und anderes Neue zur Flora von Wien, Niederösterreich und dem Burgenland. - Linzer Biol. Beitr. 33(2): 877-903.
  • Ochsmann, J. 1998: Ein Bestand von Centaurea × psammogena GÁYER (Centaurea diffusa LAM. × Centaurea stoebe L.) am NSG Sonnenstein (Thüringen). - Florist. Rundbr. 31(2): 118-125.
  • Ochsmann, J. 2000: Morphologische und molekularsystematische Untersuchungen an der Centaurea stoebe L.-Gruppe (Asteraceae-Cardueae) in Europa. - Diss. Bot. 324: 242 pp.
  • Prasse, R. & Ristow, M. 1995: Die Gefäßpflanzen einer Berliner Güterbahnhofsfläche (Schöneberger Straße) im vierten Jahrzehnt der Sukzession. - Verh. Bot. Ver. Berlin Brandenburg 128: 165-192.
  • Rechinger, K.H. 1950: Notizen zur Adventiv- und Ruderalflora von Wien. - Oesterr. Bot. Z. 97: 114-123.
  • Schaberg, F. 1965: Eine Bastardpopulation von Centaurea diffusa Lamk. und Centaurea stoebe L. in Halle. - Wiss. Z. Martin-Luther-Univ. Halle-Wittenberg, Math.-Naturwiss. Reihe 14(6): 502-503.
  • Schaberg, F. 1965: Eine Bastardpopulation von Centaurea stoebe L. und Centaurea diffusa Lamk. in Halle (Saale). - Wiss. Beiträge. Päd. Inst. Halle-Kröllwitz 1965: 31-34.
  • Verloove, F. 2006: Catalogue of neophytes in Belgium (1800-2005) - Scripta Botanica Belgica (in press)
  • Zinsmeister, J.B. 1916: Centaurea diffusa Lam. × rhenana Bor. = C. Zimmermanniana mh. - Mitt. Bayer. Bot. Ges. 3: 282.
Remarks / Anmerkungen: This hybrid has been often overlooked or confused with Centaurea diffusa LAM.
(last updated: 29.01.2007)

Centaurea scabiosa L. (1753) Sp. pl.: 913.
    = Acrocentron scabiosa (L.) Á. & D. Löve (1961) in Bot. Notis. 114: 44.
    = Colymbada scabiosa (L.) Holub (1972) in Folia Geobot. Phytotax. 7: 316.
    Common names: E. scabious knapweed, greater knapweed, greater centaury; F. centaurée scabieuse; G. Skabiosen-Flockenblume


Centaurea solstitialis L. (1753) Sp. pl.: 917.
    = Calcitrapa solstitialis (L.) Lam. (1778), Fl. Fr. 2: 34 ("solsticialis").
    = Cyanus solstitialis (L.) Baumg. (1816) Enum. Stirp. Transsilv. 3: 77.
    = Leucantha solstitialis (L.) Á. Löve & D. Löve (1961) Bot. Notis. 114: 44.
    Common names: E. Barnaby's thistle, yellow star-thistle; F. centaurée du solstice; G. Sonnenwend-Flockenblume; Swed. stjärnklint
    Distribution map for NW America from Invaders Database System


Centaurea_stoebe_micranthos_04_Stamp.jpg (3179 Byte) Centaurea stoebe L. subsp. micranthos (Gugler) Hayek (1931) Repert. Spec. Nov. Regni Veg., Beih. 30(2): 766.
    Typus: Gugler (1907: 169): "C. Baenitz, Herb. europ. sine No. (2 Bg.); diese von Borbás bei Budapest gesammelten Belege sind äußerst typisch". (BP, Isotypus?: M)
    Basionym: Centaurea maculosa Lam. subsp. micranthos Gugler 1907 Centaur. Ungar. Nationalmus.: 167.
    Common names: E. [small-headed] spotted knapweed; F. centaurée maculée, centaurée tachetée; G. Kleinköpfige Rispen-Flockenblume; Swed. sandklint
   Distribution map for NW America from Invaders Database System

Note: According to herbarium studies reports for Centaurea paniculata L. (E. panicled knapweed; F. centaurée paniculée) from N America refer to this taxon.

References:
  • Ochsmann, J. 2000: Morphologische und molekularsystematische Untersuchungen an der Centaurea stoebe L.-Gruppe (Asteraceae-Cardueae) in Europa. - Diss. Bot. 324: 242 pp.
  • Ochsmann, J. 2001: On the taxonomy of spotted knapweed (Centaurea stoebe L.). In: Smith, L. (ed.): Proceedings of the International Knapweed Symposium, March 15-16, 2001. USDA-ARS, Coeur d’Alene, ID.

Amberboa_muricata_et_Centaurea_sulphurea_01_Stamp.jpg (6584 Byte) Centaurea sulphurea Willd. (1809) Enum. Hort. Berol.: 930.
    = Calcitrapa sulphurea (Willd.) Soják (1972) Cas. Nár.. Muz., Odd.Prir. 140: 133.
    Common names: E. sulphur knapweed
    Distribution map for NW America from Invaders Database System

Centaurea trichocephala M. Bieb. ex Willd. (1803) Spec. Pl. 3(3): 2286.
    = Jacea trichocephala (Willd.) Soják (1972) in Cas. Nár. Muz., Odd. Prir. 140: 133.
    Common names: E. hairy head knapweed
Distribution map for NW America from Invaders Database System


??? Centaurea triumfettii ALL. (1773) Auct. Syn. Stirp. Hort. Taurin.: 16. 
    = Cyanus triumfettii (All.) A. Löve & D. Löve (1976) Bot. Not. 114: 44.

Note: The Invaders Database System and others list this species as synonym of C. virgata, but in fact both species belong to different sections of Centaurea. C. triumfettii is closely related to C. montana. The report is based on a misreading of C. virgata for C. variegata, a synonym of C. triumfettii.


Centaurea virgata subsp. squarrosa Gugler (1907) Centaur. Ungar. Nationalmus.: 248.
    = Centaurea virgata var. squarrosa Boiss. (1875) Fl. Orient. 3: 651.
    = Acosta squarrosa [Willd.] Soják (1972) Cas. Nár.Muz., Odd. Prir. 140: 134. 
    = Centaurea squarrosa Willd. non Roth (1803) Spec. Pl. 3(3): 2319, nom. illeg.
    Distribution map for NW America from Invaders Database System [under "C. squarrosa"]

Note: According to Wagenitz (1972: 482) Willdenow's name is a homonym of C. squarrosa Roth (1800) Catalecta 2: 118, which was validly published. Unfortunately its type was destroyed with the Berlin-Dahlem herbarium (B) during World War II, so that its identity remains unclear. "C. squarrosa Willd." clearly belongs to C. virgata Lam., a very variable group that needs further investigation.

References:
  • WAGENITZ, G. 1972: Beiträge zur Kenntnis der Gattung Centaurea L. 1. Zur Taxonomie türkischer Arten der Sektionen Acrolophus und Acrocentron. - Willdenowia 6(3): 479-508.
  • WAGENITZ, G. 1975: Centaurea. In: DAVIS, P.H. (Ed.): Flora of Turkey and the East Aegean Islands. 5: 465-585.

Mantisalca Cass.


Mantisalca salmantica (L.) Briq. & Cav.
    = Centaurea clusii (Spach) ined.
    =
Centaurea duriaei (Spach) Rouy
    = Centaurea microlonchus Salzm.
    = Centaurea salmantica L.
   
= Microlonchus clusii Spach
   
= Microlonchus duriaei Spach
   
= Microlonchus salmanticus (L.) DC.
    Common names / Volksnamen: E. dagger-flower; It. Fiordaliso di Salamanca

    Native to S Spain and NW Africa. A grain and bird seed casual.

References:
  • Clement, E.J. & Foster, M.C. 1994: Alien plants of the British Isles. B.S.B.I., London, 590 pp.

Plectocephalus D. Don in R. Sweet (1830) Brit. Flow. Gard. Ser. 2. t. 51.
    = Centaurea L. sect. Plectocephalus (D. Don) DC.

Note: According to molecular studies by Susanna et al. (1995) Plectocephalus is basal in the Centaureinae and not closely related to Centaurea s.l.

References / Literatur:
  • Susanna, A., Garcia-Jacas, N., Soltis, D.E. & Soltis, P.S. 1995: Phylogenetic relationships in tribe Cardueae (Asteraceae) based on ITS sequences. - Amer. J. Bot. 82(8): 1056-1068

Plectocephalus americanus (Nutt.) D. Don (1831) in Sweet: Brit. Fl. Gard. ser. 2: t. 51.
    = Centaurea americana Nutt. (1821) in J. Acad. Nat. Sci. Philad. 2(1): 117.
  
Common names / Volksnamen: E. American star-thistle, American basket flower, powderpuff thistle, thornless thistle; Sp. cardo del valle

   Chromosome no. / Chromosomenzahl (2n): 26 (Smith 1969; Hellwig 1994)

   Distribution / Verbreitung: Texas Distribution by vegetation zone from TAMU Database

References / Literatur:
  • HELLWIG, F.H. 1994: Chromosomenzahlen aus der Tribus Cardueae (Compositae). - Willdenowia 24: 219-248.
  • Smith, E.B. 1969. In IOPB chromosome number reports. XXII. Taxon 18: 433--442.

Plectocephalus rothrockii (Greenm) D.J.N. Hind (1996) Kew Mag. 13: 5.
    = Centaurea rothrockii
Greenm. (1904) Bot. Gaz. 37: 221.
   
Common names / Volksnamen: E. Rothrock's knapweed, Mexican basket flower

    Distribution / Verbreitung: N America: USA (Arizona, New Mexico, N Mexico)


Volutaria Cass.


Volutaria muricata (L.) Maire
    = Centaurea muricata L.
    = Amberboa muricata
(L.) DC.
    = Volutarella muricata
(L.) Benth. & Hook.f.
    = Cyanopsis muricata (L.) Dostál

    Common names: E. Morocco knapweed

    Native in the W Mediterranean