Rapistrum

Crantz

Cl. Crucif. Emend., 105. 1769.

Common names: Wild-turnip turnipweed
Etymology: Latin rapa, turnip, and -astrum, incomplete resemblance
Treatment appears in FNA Volume 7. Treatment on page 440. Mentioned on page 232, 238, 441.
 TaxonIllustrator 
FNA7 P54 Raphanus rapanistrum.jpegRaphanus raphanistrum
Rapistrum rugosum
Sinapis alba
Yevonn Wilson-Ramsey
Yevonn Wilson-Ramsey
Yevonn Wilson-Ramsey

Annuals [perennials]; not scapose; glabrous or pubescent. Stems erect, unbranched or branched basally. Leaves basal and cauline; petiolate or subsessile; basal not rosulate, petiolate, blade margins usually pinnate to lyrately pinnatifid, rarely undivided, dentate; cauline subsessile or shortly petiolate, blade (base not auriculate), margins lobed, subentire, or dentate. Racemes (corymbose, several-flowered), greatly elongated in fruit. Fruiting pedicels erect [ascending], (usually appressed to rachis), slender to stout. Flowers: sepals ascending, oblong, lateral pair not saccate basally, (hispid [glabrous or with subapical tuft of hairs]); petals yellow, obovate, claw differentiated from blade, (apex ± truncate); stamens tetradynamous; filaments not dilated basally; anthers ovate to suboblong, (apex obtuse); nectar glands confluent, median glands present. Fruits silicles, indehiscent, sessile, segments 2, elliptic to oblong, torulose, (slightly to strongly constricted at transverse joint), terete or angular; (valvular segment persistent, dehiscent [indehiscent], 1 (–3) -seeded, longitudinally striate or smooth, occasionally seedless and nearly as wide as pedicel; terminal segment indehiscent, caducous at maturity, usually 1-seeded, rarely seedless); valves glabrous or pubescent; septum complete; ovules 2–4; (style persistent, filiform); stigma capitate, (flattened), 2-lobed. Seeds uniseriate, slightly compressed, not winged, ovoid [oblong]; seed-coat (smooth), not mucilaginous when wetted; cotyledons conduplicate. x = 8.

Distribution

Introduced; s Europe (Mediterranean region), also nearly worldwide

Discussion

Species 2 (1 in the flora).

Both species of Rapistrum have been introduced into North America; only R. rugosum has persisted with naturalized populations. Rapistrum perenne (Linnaeus) Allioni was first collected in 1922 from southeastern Saskatchewan but has not been seen or collected from there since 1932. It can be distinguished by being a perennial with a conical style shorter than the strongly 8-ribbed terminal segment, whereas R. rugosum is an annual with a slender, filiform style longer than the slightly ribbed terminal segment.

Selected References

None.

Lower Taxa

"elongated" is not a number."thick" is not a number.

... more about "Rapistrum"
ovate +  and suboblong +
Suzanne I. Warwick +
Crantz +
appendaged +  and unappendaged +
not +  and auriculate +
dentate +  and undivided +
usually pinnate +  and lyrately pinnatifid +
much smaller +  and reduced +
urceolate +, campanulate +  and tubular +
branched +  and simple +
petiolate +  and subsessile +
well-developed +
distinct +
differentiated +
Wild-turnip +  and turnipweed +
emarginate +  and entire +
incumbent +, accumbent +  and conduplicate +
s Europe (Mediterranean region) +  and also nearly worldwide +
straight +  and curved +
Latin rapa, turnip, and -astrum, incomplete resemblance +
not winged +  and unappendaged +
connate +  and distinct +
actinomorphic +
indehiscent +  and dehiscent +
terete +  and segmented +
subsessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
dentate +  and entire +
dentate;subentire;dentate;subentire;lobed +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
rudimentary +
obovate +
trinucleate +  and 3(-11)-colpate +
Cl. Crucif. Emend., +
slender +  and stout +
flattened +  and rounded +
mucilaginous +
aseriate +, uniseriate +  and biseriate +
not +  and mucilaginous +
white +, black +, brown +  and yellow +
ovoid +  and compressed +
elliptic +  and oblong torulose punct terete or angular +
persistent +  and caducous +
distinct +
reduced +
indehiscent +  and dehiscent +
terete +  and segmented +
indehiscent +  and dehiscent +
terete +  and segmented +
tetradynamous +
branched +  and unbranched +
procumbent +  and decumbent +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
Cruciferae +
Rapistrum +
Brassicaceae tribe Brassiceae +
seedless +  and 1-seeded +
scale-like +  and forked +
coiled +, 1-7-veined +  and veined +
pubescent +  and glabrous +
seedless +  and 1(-3)-seeded +
anastomosing +
pubescent +  and glabrous +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +