The largest family of flowering plants , the Compositae (Asteraceae), comprising about 1,100 genera and more than 20,000 species and characterized by many small flowers arranged in a head looking like a single flower and subtended by an involucre of bracts. A head may consist of both ray flowers and disk flowers, as in the sunflower, of disk flowers only, as in the burdock, or of ray flowers only, as in the dandelion.
The Lactuceae are a tribe of closely related genera of the sunflower family that are easily recognized because the flowering heads are composed of wholly of ligulate florets that are usually 5-lobed. Another very distinguishing feature is the milky sap . Although not apparent without magnification, the pollen is distinctive in that the spines are more or less restricted to discrete ridges or flanges on the surface of the grain. In other members of the family the spines are distributed more or less evenly over the surface of the pollen grain . The pappus usually consists of scales or stiff hairs . -- Gerald D. Carr.
, biennials, or perennials
, 3-120 cm; usually taprooted, sometimes rhizomatous
deep or shallow, woody or fibrous
, caudices often woody). Stems 1-20+. erect
) or branched, usually striate
, often densely hispid
). Leaves basal (often in rosettes) and cauline; petiolate
(at least basal, petioles
) ; basal blades mostly elliptic
, or lanceolate to linear
, or spatulate
, often lyrate or runcinate, margins
, serrate, toothed
, or pinnately lobed
sometimes toothed; cauline usually present, lobed or entire, usually reduced in size and lobing distally. Heads (erect) usually in cymiform, corymbiform
, or paniculiform
arrays, sometimes borne singly. Peduncles not inflated
distally, not bracteate
. Calyculi of 5-12, reduced, subulate
to lanceolate or deltate bractlets
in ± 1 series, mostly unequal, glabrous, tomentulose
, or setose. Involucres cylindric
(sometimes becoming turbinate
in fruit), 4-15 mm diam. Phyllaries 5-18 in 1-2 series. lanceolate, equal or subequal
becoming thickened and keeled
, keels sometimes pronounced in fruit) margins green to yellowish, often scarious
, apices acute to acuminate, abaxial
, or setose, sometimes stipitate-glandular, adaxial
glabrous or with appressed
hairs. Receptacles flat or convex
, usually pitted
, glabrous or hairy, epaleate [paleate, paleae narrow, thin]. Florets 5-100+; corollas usually yellow or orange, sometimes white, pink, or reddish. Cypselae monomorphic
. yellow, brown, green, red, and/or black, subcylindric
or subterete, usually curved
, apices tapered or beaked
10-20, sometimes spiculate-roughened, faces glabrous or hispidulous
; pappi persistent
or falling, of 80-150, usually distinct
, sometimes basally connate
, white to tawny
to fine, ± equal (or outer shorter), barbellulate
in 1-2 series. x = 3, 4, 5, 6, 11.
Species ca. 200: North America, Eurasia , Africa; introduced nearly worldwide.
Crepis is generally recognized by the rosettes of coarse, often pinnately lobed leaves, erect heads, epaleate receptacles, calyculate involucres. yellow corollas, subcylindric or fusiform, ribbed cypselae, and pappi of barbellulate bristles. The taxonomy and evolutionary relationships of Crepis were studied by E. B . Babcock (1947) and his associates. Their work was thorough and important because of the effort to incorporate cytogenetic information in the evolutionary analysis. Extensive survey of chromosome number and karyotype indicated two major ploidy groups in Crepis, corresponding to New World and Old World species complexes. Of the 12 species of Crepis native to North America, 10 are polyploids with x = 11. The core diploid populations commonly occupy discrete ecologic zones and are thought to be entirely distinct from one another, yet they are interconnected by a continuous complex series of intergrading polyploid forms that are partly or completely apomictic (Babcock). The polyploids are of two forms, autopolyploids that are similar to the diploids, and allopolyploids that combine the characteristics of two or more diploid species. The allopolyploid forms of hybrid origin may exhibit the characteristics of multiple parental species and therefore are difficult to classify. Some of the heterogeneous apomictic populations, or groups of populations, have been grouped together and recognized as subspecies ; those taxa are often difficult to identify and further study is clearly needed. Despite these difficulties, the subspecific taxa of Babcock were tentatively included in the present study. The Old World species are mostly diploid (n = 3, 4, 5, or 6). Babcock concluded that there was a progressive decrease in the chromosome numbers, from n = 6 to n = 3. Along with the decrease is a corresponding increase in chromosome asymmetry and reduction in chromosome length.
- Whittaker & Margulis,1978
- Haeckel, 1866
- Cavalier-Smith, 1981
- Sinnott, 1935 ex Cavalier-Smith, 1998
- Vascular Plants
- Brongniart, 1843
- Takhtajan, 1967
- Takhtajan Ex Reveal, 1992
- Lindley, 1833
- Giseke, 1792, nom. cons., nom. alt.
- Subfamily: Cichorioideae ()
- Family: Compositae () - Giseke, 1792, nom. cons., nom. alt.
- Order: Asterales () - Lindley, 1833
- Superorder: Campanulanae () - Takhtajan Ex Reveal, 1992
- Subclass: Asteridae () - Takhtajan, 1967
- Class: Spermatopsida () - Brongniart, 1843
- Subphylum: Euphyllophytina ()
- Phylum: Tracheophyta () - Sinnott, 1935 ex Cavalier-Smith, 1998 - Vascular Plants
- Subkingdom: Viridaeplantae () - Cavalier-Smith, 1981
- Kingdom: Plantae () - Haeckel, 1866 - Plants
Status: Accepted Name
Comment: Data Providers: Govaerts World Compositae Checklist A-G, IPNI, Tropicos, Euro+Med. GCC LSID: urn :lsid:compositae.org:names:CBBD8E18-9920-4C00-AE5D-F9B9C5245571
Last scrutiny: 25-Aug-09
Members of the genus Crepis
ZipcodeZoo has pages for 44 species, subspecies, varieties, forms, and cultivars in this genus:
C. acuminata (Long-Leaf Hawksbeard) · C. acuminata acuminata (Longleaf Hawksbeard) · C. acuminata pluriflora (Longleaf Hawksbeard) · C. atribarba (Hawksbeard) · C. atribarba atribarba (Hawksbeard) · C. aurea (Golden Hawks Beard) · C. bakeri (Baker's Hawksbeard) · C. bakeri cusickii (Baker's Hawksbeard) · C. bakeri idahoensis (Baker's Hawksbeard) · C. biennis (Rough Hawksbeard) · C. bursifolia (Italian Hawksbeard) · C. capillaris (Smooth Hawk's-Beard) · C. elegans (Elegant Hawksbeard) · C. foetida (Roadside Hawksbeard) · C. foetida foetida (Stinking Hawksbeard) · C. intermedia (Gray Hawksbeard) · C. modocensis rostrata (Common Hawksbeard) · C. monticola (Mountain Hawksbeard) · C. nana (Dwarf Alpine Hawksbeard) · C. nana ramosa (Dwarf Alpine Hawksbeard) · C. nicaeensis (Turkish Hawksbeard) · C. occidentalis conjuncta (Gray Hawksbeard) · C. occidentalis pumila (Large-Flower Hawk's-Beard) · C. pannonica (Pasture Hawksbeard) · C. pleurocarpa (Naked-Stem Hawksbeard) · C. pulchra (Hawksbeard) · C. pulchra pulchra (Smallflower Hawksbeard) · C. pumila (Largeflower Hawksbeard) · C. rostrata (Modoc Hawksbeard) · C. rubra (Hawksbeard) · C. rubra 'Alba' (Hawks Beard) · C. runcinata andersonii (Dandelion Hawksbeard) · C. runcinata barberi (Barber's Hawksbeard) · C. runcinata hallii (Fiddleleaf Hawksbeard) · C. runcinata hispidulosa (Fiddleleaf Hawksbeard) · C. runcinata imbricata (Fiddleleaf Hawksbeard) · C. runcinata runcinata (Fiddle-Leaf Hawk's-Beard) · C. setosa (Bristly Hawksbeard) · C. tectorum (Narrow-Leaf Hawk's-Beard) · C. tectorum tectorum (Narrowleaved Hawk's Beard) · C. vesicaria (Beaked Hawksbeard) · C. vesicaria haenseleri (Beaked Hawksbeard) · C. vesicaria taraxacifolia (Beaked Hawksbeard) · C. zacintha (Striped Hawksbeard)
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- An encyclopaedia of gardening; comprising the theory and practice of horticulture, floriculture, arboriculture, and landscape-gardening, including all the latest improvements; a general history of gardening in all countries; and a By J.C. Loudon. Illustrated with many hundred engravings on wood by Branston. London: Longman, Hurst, Rees, Orme, Brown, and Green, 1825. url p. 885.
- An encyclopædia of gardening; comprising the theory and practice of horticulture, floriculture, arboriculture, and landscape-gardening, including all the latest improvements; a general history of gardening in all countries; and a By J.C. Loudon. .. illustrated with many hundred engravings on wood by Branston. London: Printed for Longman, Rees, Orme, Brown, and Green, 1827. url p. 885.
- Bulletin of miscellaneous information /Royal Botanic Gardens, Kew. 1901 London: H.M. Stationery Office, 1900-1941. url p. 10.
- Compositae newsletter. Columbus, Ohio: Dept. of Botany, Ohio State University, 1975- url p. 44, p. 46, p. 9.
- Flora of the U.S.S.R. [Springfield, Va.: Israel Program for Scientific Translations; 1968- url p. 679.
- Hand-list of herbaceous plants cultivated in the Royal Botanic Gardens. London, Printed for H. M. Stationery Off. by Darling, 1902. url p. 341.
- Handbook of flower pollination based upon Hermann Müller's work 'The fertilisation of flowers by insects'; tr. by J.R. Ainsworth Davis. Oxford, Clarendon Press, 1906. url p. 586.
- Handbook of flower pollination: based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' / Oxford: Clarendon Press, 1906-09. url .
- Hortus suburbanus Calcuttensis; A catalogue of the plants which have been cultivated in the Hon. East India Company's botanical garden, Calcutta, and in the Serampore botanical garden. By the late J. O. Voigt, printed under the superintendence of W. Griffith. Calcutta, Bishop's College Press, 1845. url p. 431.
- Introduction to cytology, by Lester W. Sharp. .. New York, McGraw-Hill Book Company, inc., 1934. url p. 372.
- List of rare, threatened and endemic plants in Europe (1982 edition) Council of Europe url p. 312.
- Physiological genetics, by Richard Goldschmidt. New York, McGraw-Hill Book Company inc., 1938. url p. 149.
- Sweet's Hortus britannicus: or a catalogue of plants cultivated in the gardens of Great Britain, arranged in natural orders / by Robert Sweet. London: J. Ridgway, 1826. url p. 210.
- The Annals of Scottish natural history. Edinburgh: David Douglas, 1892-1911. url p. 100, p. 48.
- The Garden: an illustrated weekly journal of gardening in all its branches. London: [s.n., url p. 500.
- The Gardeners' chronicle: a weekly illustrated journal of horticulture and allied subjects. London: [Gardeners Chronicle], 1874-1955. url p. 172.
- The Philosophical transactions of the Royal society of London, from their commencement in 1665, in the year 1800. London, Printed by and for C. and R. Baldwin, 1809. url p. 201.
- The natural history of plants, their forms, growth, reproduction, and distribution; Dublin, Blackie & son, limited, 1902. url , .
- The natural history of plants; their forms, growth, reproduction, and distribution. From the German of Anton Kerner von Marilaun by F. W. Oliver, with the assistance of Marian Busk and Mary F. Ewart. London, Blackie, 1894-1895. url p. 215.
- Transactions of the Edinburgh Field Naturalists' and Microscopical Society. [Edinburgh]: The Club, 1891- url p. 138.
- University of California publications in agricultural sciences. Berkeley, University of California Press. url p. 318, p. 320, p. 329, p. 382.
- Babcock, E. B. 1947. The genus Crepis. Pt. 1: The taxonomy, phylogeny, distribution, and evolution of Crepis. Pt. II: Systematic treatment. Univ. Calif. Publ. Bot. 21, 22.
- Brands, S.J. (comp.) 1989-present. The Taxonomicon. Universal Taxonomic Services, Zwaag, The Netherlands. Accessed January 10, 2012.
- Biodiversity Heritage Library NamebankID: 5831766
- Catalogue of Life Accepted Name Code: Ast-6469
- Global Biodiversity Information Facility Taxonkey: 15123715
- Globally Unique Identifier: urn:lsid:ipni.org:names:199655-1
- Zipcode Zoo Species Identifier: 2086933