Carduus crispus L.:
Canada (North America)
China (Asia)
Kazakhstan (Asia)
Mongolia (Asia)
North Korea (Asia)
Russian Federation (Asia)
South Korea (Asia)
United States (North America)

Canada

Origin: Exotic

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

United States

Origin: Exotic

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

Canadian distributions above follow R. J. Moore and C. Frankton (1974); I have not seen those specimens. Carduus crispus has been reported also from Arkansas, Connecticut, Iowa, Illinois, Maine, Maryland, Massachusetts, Missouri, New York, North Dakota, Ohio, Rhode Island, Vermont, Virginia, and West Virginia; I have not seen specimens from those states.

Two subspecies of Carduus crispus have been recognized (S. M. A. Kazmi 1964); those are not differentiated here.

Carduus crispus closely resembles the much more common C. acanthoides. Some published records of C. crispus are probably C. acanthoides. Although the degree of spininess and tough versus brittle stems were used as key characters (A. Cronquist 1980; H. A. Gleason and A. Cronquist 1991) to differentiate the two taxa, both characters are subjective, and the second is impractical with dry material.

Annuals or biennials, 30–150 cm. Stems openly branching, villous with curled, septate hairs to nearly glabrous, spiny wings to 1.5 cm wide, wing spines to 3 mm. Leaves: basal tapering to winged petioles, blades 10–20 cm, margins spiny-toothed to ± shallowly pinnately lobed; cauline sessile, gradually smaller, margins often more deeply divided, marginal spines to 3 mm; abaxial leaf faces ± tomentose with long, one-celled hairs and/or long, curled, septate hairs along veins or glabrate; adaxial faces sparsely hairy or glabrate. Heads borne singly or in groups of 2–5, 15–18 mm. Peduncles spiny-winged to near apex or throughout, to 4 cm. Involucres ± spheric, 12–17 × 12–17 mm. Phyllaries narrowly lanceolate, outer and middle with appressed bases ca. 1 mm wide and appressed to spreading appendages 0.5–1 mm wide, spine tips 1–1.5 mm, inner with unarmed, straight tips. Corollas purple or ± white, 11–16 mm, lobes ca. 3.5 times length of throat. Cypselae light brown to gray-brown, 2.5–3.8 mm; pappus bristles 11–13 mm. 2n = 16 (Sweden).

Foodplant / sap sucker
Brachycaudus cardui sucks sap of Carduus crispus

Foodplant / internal feeder
larva of Chaetostomella cylindrica feeds within capitulum of Carduus crispus

Foodplant / internal feeder
larva of Cheilosia mutabilis feeds within root of Carduus crispus

In Great Britain and/or Ireland:
Foodplant / parasite
Golovinomyces cichoracearum parasitises live Carduus crispus

Foodplant / open feeder
larva of Lema cyanella grazes on windowed leaf (upper surface) of Carduus crispus

Foodplant / saprobe
scattered, immersed, neck erumpent pseudothecium of Ophiobolus cirsii is saprobic on dead stem of Carduus crispus

Foodplant / parasite
mostly hypophyllous telium of Puccinia calcitrapae parasitises live leaf of Carduus crispus
Other: minor host/prey

Foodplant / parasite
Puccinia cnici parasitises live Carduus crispus
Remarks: Other: uncertain

Foodplant / parasite
amphigenous telium of Puccinia cnici-oleracei parasitises live leaf of Carduus crispus
Remarks: season: 7-11
Other: minor host/prey

Foodplant / spot causer
amphigenous colony of Ramularia hyphomycetous anamorph of Ramularia cynarae causes spots on live leaf of Carduus crispus

Foodplant / internal feeder
larva of Tephritis hyoscyami feeds within capitulum of Carduus crispus

Foodplant / feeds on
larva of Terellia serratulae feeds on Carduus crispus

Foodplant / internal feeder
larva of Terellia winthemi feeds within capitulum of Carduus crispus
Other: major host/prey

Foodplant / gall
larva of Urophora solstitialis causes gall of capitulum of Carduus crispus

Foodplant / feeds on
larva of Urophora stylata feeds on Carduus crispus
Remarks: Other: uncertain

Foodplant / internal feeder
larva of Xyphosia miliaria feeds within capitulum of Carduus crispus

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Species: 2
Species With Barcodes: 1

Canada

Rounded National Status Rank: NNA - Not Applicable

United States

Rounded National Status Rank: NNA - Not Applicable

Rounded Global Status Rank: GNR - Not Yet Ranked