Eutrema

R. Brown

Chlor. Melvill., 9, plate A. 1823.

Etymology: Greek eu- , well, and trema, hole, alluding to perforation in fruit septum
Synonyms: Neomartinella Pilger Platycraspedum O. E. Schulz Thellungiella O. E. Schulz Wasabia Matsumura
Treatment appears in FNA Volume 7. Treatment on page 555. Mentioned on page 226, 231, 233, 246.
 TaxonIllustrator 
FNA7 P68 Strigosella africana.jpegStrigosella africana
Eutrema edwardsii
Halimolobos jaegeri
Yevonn Wilson-Ramsey
Yevonn Wilson-Ramsey
Yevonn Wilson-Ramsey

Annuals or perennials; (caudex simple or branched), [rhizomatous]; not scapose. Stems erect or ascending [decumbent], unbranched or branched distally. Leaves basal and cauline; petiolate or sessile; basal rosulate or not, petiolate, blade margins usually entire or palmately lobed, rarely dentate or pinnatifid, (pinnately or palmately veined); cauline petiolate or sessile, blade (base cuneate or sagittate-amplexicaul), margins entire or repand [dentate, crenate], (pinnately or palmately veined, ultimate veins sometimes ending with apiculate callosities). Racemes (corymbose). Fruiting pedicels divaricate to ascending, slender or stout. Flowers: sepals ovate or oblong; petals usually spatulate, rarely obovate, claw not differentiated from blade, (apex obtuse to emarginate); stamens slightly tetradynamous; filaments slightly dilated basally; anthers ovate or oblong, (apex obtuse); nectar glands confluent, often subtending bases of stamens, median glands present or absent. Fruits sessile or shortly stipitate, linear or oblong [ovoid, lanceoloid], smooth or torulose, terete, slightly 4-angled, latiseptate, or angustiseptate; valves each with obscure or prominent midvein; replum rounded; septum complete or perforated; ovules [2–] (6–) 8–96 per ovary; stigma capitate. Seeds usually uniseriate, rarely biseriate, plump, not winged, oblong or ovoid; seed-coat (usually obscurely reticulate, rarely foveolate or papillate), often not mucilaginous when wetted; cotyledons incumbent [rarely accumbent].

Distribution

North America, c, e Asia (Himalayas)

Discussion

Species 26 (2 in the flora).

The fleshy rhizomes of the eastern Asian Eutrema japonicum (Siebold) Maximowicz are pungent and are the main source of true wasabi (W. H. Hodge 1974). Paste of horseradish (Armoracia rusticana) is often used as an inexpensive substitute.

Molecular studies, combined with a critical evaluation of morphology, have shown that Thellungiella is nested within, and hardly distinct from, the earlier-published Eutrema, and therefore the two genera have been combined (I. A. Al-Shehbaz and S. I. Warwick 2005; Warwick et al. 2006).

Key

1 Perennials; cauline leaf blades: bases cuneate, not auriculate or sagittate; ovules (6-)8-12 (-14) per ovary. Eutrema edwardsii
1 Annuals; cauline leaf blades: bases usually sagittate-amplexicaul, rarely auriculate; ovules 55-96 per ovary. Eutrema salsugineum

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

... more about "Eutrema"
oblong +  and ovate +
Ihsan A. Al-Shehbaz +
R. Brown +
not +  and rosulate +
appendaged +  and unappendaged +
not auriculate +
pinnatifid +, dentate +, lobed +  and entire +
much smaller +  and reduced +
urceolate +, campanulate +  and tubular +
branched +  and simple +
sessile +  and petiolate +
well-developed +
not differentiated +
emarginate +  and entire +
North America +, c +  and e Asia (Himalayas) +
straight +  and curved +
Greek eu- , well, and trema, hole, alluding to perforation in fruit septum +
not winged +  and unappendaged +
connate +  and distinct +
actinomorphic +
latiseptate +, stipitate +  and sessile +
angustiseptate +, 4-angled +, terete +, torulose +, oblong +  and linear +
latiseptate +  and unsegmented +
angustiseptate +, 4-angled +  and terete +
latiseptate +  and unsegmented +
angustiseptate +, 4-angled +  and terete +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
emarginate to 2-fid +  and entire +
repand;entire +
prominent +  and obscure +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
pink +  and white +
rudimentary +
obovate +  and spatulate +
trinucleate +  and 3(-11)-colpate +
Chlor. Melvill., +
bracteate;ebracteate +
stout +  and slender +
al-shehbaz2005b +
mucilaginous +
not +  and mucilaginous +
white +, black +, brown +  and yellow +
ovoid +  and oblong +
persistent +  and caducous +
distinct +
oblong +  and ovate +
perforated +  and complete +
reduced +
latiseptate +, schizocarpic +, samaroid +  and lomentaceous +
indehiscent +  and dehiscent +
angustiseptate +, flat +, angled +, terete +, torulose +, not +, segmented +  and nutletlike +
tetradynamous +
branched +  and unbranched +
procumbent +  and decumbent +
ascending +  and erect +
2-lobed +, entire +, conical +  and capitate +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
Neomartinella +, Platycraspedum +, Thellungiella +  and Wasabia +
Eutrema +
Brassicaceae tribe Eutremeae +
eglandular +, peltate +, malpighiaceous +, dendritic +, sessile +, stalked +, simple +  and unicellular +
scale-like +  and forked +
coiled +, 1-7-veined +  and veined +
pubescent +  and glabrous +
anastomosing +
perennial +  and annual +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +