Arabidopsis lyrata

(Linnaeus) O’Kane & Al-Shehbaz

Novon 7: 325. 1997.

Basionym: Arabis lyrata Linnaeus Sp. Pl. 2: 665. 1753
Synonyms: Cardaminopsis lyrata (Linnaeus) Hiitonen
Treatment appears in FNA Volume 7. Treatment on page 449. Mentioned on page 448, 450.

Biennials or perennials; (caudex branched or not, sometimes root crown present); glabrous or pubescent, trichomes simple, with stellate, forked, and rayed ones. Stems simple or few to several from base, erect or decumbent, usually branched distally, 0.5–5 dm, pubescent basally, trichomes mixed simple, 1-forked, and (fewer) stellate ones, rarely 3-rayed, glabrous or pubescent apically. Basal leaves: petiole 0.5–6 cm; blade oblanceolate or ovate, 0.5–8.5 cm × 2–18 mm, margins entire, dentate, or lyrate-pinnatifid (when lobed, terminal lobes larger than lateral), apex obtuse, surfaces glabrous or sparsely to densely pubescent. Cauline leaves shortly petiolate or sessile; blade oblanceolate, 0.4–4.2 cm × 1–8 (–10) mm (smaller distally), margins usually entire, repand, or obscurely toothed, rarely lobed. Fruiting pedicels divaricate or ascending, 2–15 mm. Flowers: sepals 2–4.5 mm, lateral pair saccate basally, (glabrous or densely pubescent); petals white or purplish, spatulate or obovate, 4–10 × 1.5–4 mm, (claw to 2 mm, toothless); filaments 2–4 mm. Fruits torulose, flattened, (1.5–) 2–4.5 cm × 0.8–1.8 mm; valves each with distinct midvein; ovules 24–46 per ovary; style 0–1 mm. Seeds light-brown, (flattened), oblong, 0.8–1.4 mm; cotyledons accumbent.

Distribution

V7 681-distribution-map.gif

Alta., B.C., Man., N.W.T., Ont., Sask., Yukon, Alaska, Conn., D.C., Del., Ill., Ind., Iowa, Mass., Md., Mich., Minn., Miss., Mo., N.C., N.J., N.Y., Ohio, Pa., Tenn., Va., Vt., W.Va., Wash., Wis., n Europe, n, e Asia

Discussion

Subspecies 3 (3 in the flora).

Arabidopsis lyrata and its infraspecific taxa recognized below were treated in Arabis by R. C. Rollins (1993) and G. A. Mulligan (1996). As shown by S. L. O’Kane and I. A. Al-Shehbaz (1997, 2003), the two genera are relatively distantly related and A. lyrata should be placed in Arabidopsis with the rest of its relatives.

Arabidopsis lyrata is highly variable. It has been divided (see synonymy below) into independent species. The three subspecies recognized here are rather difficult to separate, especially where their ranges overlap. Cytological data are not helpful; both diploid and tetraploid populations have been reported for each of the three subspecies.

Selected References

None.

Key

1 Basal leaf blade margins entire or toothed; caudices well-developed, often branched, somewhat thickened. Arabidopsis lyrata subsp. petraea
1 Basal leaf blade margins lyrate or lyrate-pinnatifid; caudices often slender, unbranched, or with a root crown > 2
2 Basal leaf blade surfaces usually pubescent; petioles often hirsute; petals 6-8 mm; fruits 0.8-1 mm wide; styles 0.5-1 mm. Arabidopsis lyrata subsp. lyrata
2 Basal leaf blade surfaces glabrous or sparsely pubescent; petioles often glabrous; petals (4-) 5-5.5(-6) mm; fruits 1.2-1.5(-1.8) mm wide; styles 0-0.5 mm. Arabidopsis lyrata subsp. kamchatica

"elongated" is not a number."thick" is not a number."dm" is not declared as a valid unit of measurement for this property.

... more about "Arabidopsis lyrata"
ovate +  and oblong +
Ihsan A. Al-Shehbaz +
(Linnaeus) O’Kane & Al-Shehbaz +
Arabis lyrata +
appendaged +  and unappendaged +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (4.2 cm42 mm <br />0.042 m <br />) +
lyrate +, lobed +, toothed +  and entire +
oblanceolate;ovate;oblanceolate +
much smaller +  and reduced +
1mm;8mm +
urceolate +, campanulate +  and tubular +
branched +  and simple +
sessile +  and petiolate +
well-developed +
distinct +
differentiated +
emarginate +  and entire +
Alta. +, B.C. +, Man. +, N.W.T. +, Ont. +, Sask. +, Yukon +, Alaska +, Conn. +, D.C. +, Del. +, Ill. +, Ind. +, Iowa +, Mass. +, Md. +, Mich. +, Minn. +, Miss. +, Mo. +, N.C. +, N.J. +, N.Y. +, Ohio +, Pa. +, Tenn. +, Va. +, Vt. +, W.Va. +, Wash. +, Wis. +, n Europe +, n +  and e Asia +
straight +  and curved +
not winged +  and unappendaged +
connate +  and distinct +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
actinomorphic +
2-valved +  and capsular +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
2cm;4.5cm +
flattened +  and torulose +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
latiseptate +  and unsegmented +
indehiscent +  and dehiscent +
angustiseptate +  and terete +
latiseptate +, subsessile +  and stipitate +
terete +  and torulose +
subsessile +, sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
lyrate-pinnatifid +, dentate +  and entire +
lobed;toothed;repand;toothed;repand;entire +
obscure +  and prominent +
forked +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
0.4 cm4 mm <br />0.004 m <br /> (1 cm10 mm <br />0.01 m <br />) +
rudimentary +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (6 cm60 mm <br />0.06 m <br />) +
trinucleate +  and 3(-11)-colpate +
not elongated +
reflexed +  and ascending +
slender +
not +  and mucilaginous +
margined +  and not winged +
uniseriate +  and biseriate +
not +  and mucilaginous +
0.8mm +  and 1.4mm +
persistent +  and caducous +
distinct +
ascending +  and erect +
0.2 cm2 mm <br />0.002 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
reduced +
latiseptate +, schizocarpic +, samaroid +  and lomentaceous +
indehiscent +  and dehiscent +
angustiseptate +, flat +, angled +, terete +, torulose +, not +, segmented +  and nutletlike +
tetradynamous +
branched +, few to several +  and simple +
procumbent +  and decumbent +
decumbent +  and erect +
2-lobed +, entire +, conical +  and capitate +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
glabrous or +  and sparsely densely pubescent +
Cardaminopsis lyrata +
Arabidopsis lyrata +
Arabidopsis +
species +
pubescent +  and glabrous +
pubescent +  and glabrous +
anastomosing +
perennial +  and biennial +
pubescent +  and glabrous +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +