| | 1. Leaf hairs branched (sometimes also simple) |
| |
| | 2. Leaf deeply lobed or compound; fruit < 3 cm |
| |
| | 3. Leaf segments rigid, often sharp-pointed; fruit often flat perpendicular to septum |
| POLYCTENIUM (no key)2 |
| | 3' Leaf segments ± flexible, not sharp-pointed; fruit ± cylindric or ± flat parallel to septum |
| |
| | 4. Fruit ± cylindric, valves midribbed ± to tip; pedicel generally thread-like; petals yellow or whitish |
| DESCURAINIA |
| | 4' Fruit generally flat, valves midribbed only at base; pedicel linear, width nearly = fruit width; petals white to purplish |
| SIBARA |
| | 2' Leaf entire to generally shallowly lobed; fruit often > 3 cm |
| |
| |
| | 6. Hairs appressed, forked to multibranched; petals generally > 15 mm, blade much wider than claw |
| ERYSIMUM |
| | 6' Hairs appressed and not, simple to multibranched; petals < 15 mm, blade little wider than claw |
| |
| | 7. Seeds 1 row per chamber |
| |
| | 8. Fruit not long-tapered; taproot often ± slender; basal leaves entire or dentate, generally < 10 cm; seed often winged |
| ARABIS |
| | 8' Fruit long-tapered to tip; taproot very thick; basal leaves entire, 3–15 cm; seed unwinged |
| PHOENICAULIS (no key) |
| | 7' Seeds 2 rows per chamber |
| |
| | 9. Fruit 5–7 mm wide, tapered, sharp-pointed; seed coat silvery |
| ANELSONIA (no key)2 |
| | 9' Fruit < 5 mm wide (or tip not tapered and sharp-pointed); seed coat not silvery |
| |
| | 10. Fruit generally > 3 cm, > 10 × longer than wide; petals not yellow |
| ARABIS |
| | 10' Fruit generally < 2 cm, < 10 × longer than wide; petals often yellow |
| DRABA |
| | 5' Fruit ± flat to ± 4-sided or round in X-section |
| |
| | 11. Stigma lobes pointed, decurrent |
| MALCOLMIA (no key) |
| | 11' Stigma lobes not pointed, decurrent or not |
| |
| | 12. Flower showy (petals generally > 15 mm, blade much wider than claw); fruit generally > 4 cm (inflated if shorter) |
| |
| | 13. Leaf and stem hairs appressed, forked to multibranched; petals often yellow or orange |
| ERYSIMUM |
| | 13' Leaf and stem hairs appressed and not, simple to multibranched; petals not yellow or orange |
| |
| | 14. Fruit < 3 cm, inflated; style 4–8 mm; stigma lobes not decurrent |
| AUBRIETA (no key) |
| | 14' Fruit > 3 cm, not inflated; style < 4 mm; stigma lobes ± decurrent |
| |
| | 15. Leaf dentate; leaf hairs ± sparse, simple and forked, fruit hairs generally 0 |
| HESPERIS (no key) |
| | 15' Leaf ± entire; leaf and fruit hairs dense, multibranched, rarely also simple |
| MATTHIOLA (no key) |
| | 12' Flower not showy (petals generally < 10 mm, blade little wider than claw); fruit generally < 4 cm (except Arabis glabra), not inflated |
| |
| | 16. Hairs appressed, forked to multibranched; petals yellow |
| ERYSIMUM |
| | 16' Hairs appressed or not, simple to multibranched; petals white or cream-colored, rarely lilac |
| |
| | 17. Fruit 4–10 cm; upper stem leaves clasping |
| Arabis glabra |
| | 17' Fruit < 4 cm; upper stem leaves not clasping |
| |
| | 18. Annual; fruit glabrous; seeds ± 1 row per chamber |
| ARABIDOPSIS (no key) |
| | 18' Biennial or perennial herb; fruit sometimes hairy; seeds 2 rows per chamber |
| HALIMOLOBOS |
| | 1' Leaf hairs 0 or simple (rarely branched in Caulanthus) |
| |
| | 19. Fruit stalk above pedicel 1–3 cm; stamens ± equal |
| STANLEYA |
| | 19' Fruit stalk above pedicel 0(–1) cm; stamens generally 4 long, 2 short |
| |
| | 20. Calyx ± urn- or flask-shaped, nearly closed at full flower, often brightly colored; petals generally strap-shaped (except Streptanthella) |
| |
| | 21. Fruit generally ± cylindric or ± flat parallel to septum; seed generally unwinged |
| |
| | 22. Sepals 3–18 mm, generally not green; petals 5–23 mm, blade base as wide as or narrower than claw; stigma lobes generally 2; fruit 1.5–18 cm, ± cylindric or ± flat; seed 1–4 mm, generally ± brown, wing sometimes narrow at 1 end or 0 |
| CAULANTHUS |
| | 22' Sepals 1–11 mm, greenish or not; petals 3–15 mm, blade base sometimes much wider than claw; stigma lobes 0 or 2; fruit 1–9 cm, ± cylindric; seed < 2 mm, brownish or yellowish, wing 0 |
| GUILLENIA |
| | 21' Fruit generally flat parallel to septum; seed generally winged |
| |
| | 23. Fruit pendent, valves persistent to beak |
| STREPTANTHELLA (no key) |
| | 23' Fruit ascending or pendent, valves dehiscent, falling, beak 0 |
| STREPTANTHUS |
| | 20' Calyx not urn- or flask-shaped, fully opening, generally greenish; petals generally clawed or spoon-shaped, sometimes linear to obovate |
| |
| | 24. Bracts subtending at least several flowers per inflorescence |
| |
| ERUCA (no key)STRUM* |
| TROPIDOCARPUM |
| | 24' Bracts generally 0 (may subtend a few lower flowers or main branches) |
| |
| | 26. Fruit not opening by valves |
| |
| | 27. Fruit flat, winged, oblong to oblanceolate, indehiscent, not breaking into segments |
| ISATIS (no key)2 |
| | 27' Fruit ± flat or ± round in X-section, unwinged, not oblong to oblanceolate, generally breaking into transverse segments |
| |
| | 28. Fruit beak narrow, > 5 mm; fruit breaking into 2–several 0–5-seeded segments |
| |
| | 29. Plant glandular; fruit often upcurved, not grooved |
| CHORISPORA (no key) |
| | 29' Plant not glandular; fruit straight, grooved below |
| RAPHANUS |
| | 28' Fruit beak either wide or < 5 mm; fruit breaking into 2 unlike segments, each generally 1-seeded |
| |
| | 30. Plant generally glabrous; leaf fleshy; ocean dunes; petals white to lavender; fruit 1–3 cm |
| CAKILE |
| | 30' Plant coarsely stiff-hairy; leaf not fleshy; disturbed areas (not dunes); petals yellow; fruit < 1 cm |
| RAPISTRUM (no key) |
| | 26' Fruit opening by valves |
| |
| | 31. Fruit beak prominent, generally nearly as wide as valves |
| |
| | 32. Seeds 2 rows per chamber; petals generally prominently dark-veined |
| ERUCA |
| | 32' Seeds 1 row per chamber; petals not dark-veined |
| |
| | 33. Fruit valves with 1 midvein |
| BRASSICA |
| | 33' Fruit valves with 3–7 veins, especially when young |
| |
| | 34. Fruit appressed to stem, beak base abruptly swollen |
| HIRSCHFELDIA (no key) |
| | 34' Fruit not appressed to stem, beak base generally not abruptly swollen |
| SINAPIS |
| | 31' Fruit beak generally 0 or obscure (except Brassica), narrower than valves |
| |
| | 35. Fruit generally ± flat |
| |
| | 36. Fruit clearly stalked above receptacle |
| THELYPODIUM |
| | 36' Fruit ± not stalked above receptacle |
| |
| | 37. Fruit valves without prominent midrib |
| |
| | 38. Fruit valves generally opening elastically, sometimes coiling from base |
| CARDAMINE |
| | 38' Fruit valves not opening elastically |
| SIBARA |
| | 37' Fruit valves with prominent midrib |
| |
| | 39. Leaves entire to toothed; petals white or straw to deep purple; cotyledons not doubly folded |
| ARABIS |
| | 39' Some leaves lobed; petals pale to lemon yellow; cotyledons doubly folded |
| DIPLOTAXIS |
| | 35' Fruit ± 4-sided to round in X-section |
| |
| | 40. Seeds 2 rows per chamber |
| RORIPPA |
| | 40' Seeds 1 row per chamber |
| |
| | 41. Petals white to purple |
| |
| | 42. Cauline leaves compound; wet places |
| Rorippa gambellii |
| | 42' Cauline leaves ± entire to dissected but not compound; drier places |
| |
| | 43. Plant woody at base; fruit not clearly stalked above receptacle — n White and Inyo Mountains |
| CAULOSTRAMINA (no key) |
| | 43' Plant generally not woody at base; fruit ± stalked above receptacle |
| |
| | 44. Fruit stalk < 1 mm, ± as wide as body; fruit often reflexed, not densely clustered; cauline leaves generally not clasping |
| GUILLENIA |
| | 44' Fruit stalk < to > 1 mm, narrower than body; fruit not reflexed, often densely clustered; cauline leaves often clasping |
| THELYPODIUM |
| | 41' Petals ± yellow (sometimes very pale or pinkish in Guillenia) |
| |
| | 45. Cauline leaves clasping stem |
| |
| | 46. Fruit beak > 5 mm; seed spheric |
| BRASSICA |
| | 46' Fruit beak 0 or obscure, any remaining style < 3 mm; seed not spheric |
| |
| | 47. Leaf pinnately lobed to ± compound; plant not glaucous; fruit < 8 cm |
| BARBAREA |
| | 47' Leaf ± entire; plant glaucous; fruit 8–13 cm |
| CONRINGIA (no key) |
| | 45' Cauline leaves not clasping stem |
| |
| | 48. Fruit beak > 2 mm; seed spheric |
| BRASSICA |
| | 48' Fruit beak generally 0, any remaining style < 3 mm; seed not spheric |
| |
| | 49. Fruit ascending to reflexed, 1–7 cm; petals 3–6 mm, white, pale yellow, pinkish |
| Guillenia lasiophylla |
| | 49' Fruit erect to ascending, 0.8–10 cm; petals 1.5–10 mm, (pale) yellow |
| SISYMBRIUM
|
| | 1. Leaf generally lobed to compound, sometimes entire |
| |
| | 2. Fruit transversely jointed into 2 segments; leaf very fleshy; ocean dunes |
| CAKILE |
| | 2' Fruit not transversely jointed; leaf not very fleshy; inland |
| |
| | 3. Petals white to purplish; fruit ± flat parallel to septum to ± plump; alpine |
| SMELOWSKIA (no key) |
| | 3' Petals generally yellow (whitish); fruit generally ± cylindric or plump; not alpine |
| |
| | 4. Cauline leaf 1–many-pinnately lobed to compound, 1° segments at least again lobed; hairs generally multibranched |
| DESCURAINIA |
| | 4' Cauline leaf entire to deeply lobed (rarely compound), 1° segments ± entire to toothed; hairs simple or 0 |
| RORIPPA |
| | 1' Leaf entire to shallowly lobed |
| |
| |
| | 6. Lower leaves 3–5 dm; stem 6–20 dm; fruits and seeds generally abortive |
| ARMORACIA (no key) |
| | 6' Lower leaves < 3 dm; stem generally < 5 dm; fruits and seeds generally fertile |
| |
| | 7. Plant aquatic; leaf narrowly awl-like |
| SUBULARIA (no key) |
| | 7' Plant terrestrial; leaf wider than awl-like |
| |
| | 8. Lower petioles >> blades; coastal (North Coast) |
| COCHLEARIA (no key) |
| | 8' Lower petioles 0 or not > blades; generally not near coast |
| |
| | 9. Leaf entire, < 5 mm wide; seed generally 1 per fruit |
| CUSICKIELLA |
| | 9' Leaf generally toothed or lobed, > 5 mm wide; seeds 2–many per fruit |
| |
| | 10. Fruit ± indehiscent, ± flattened or plump; seeds 2–4 |
| CARDARIA |
| | 10' Fruit dehiscent, plump; seeds several–many |
| RORIPPA |
| | 5' Some hairs generally forked, stellate, or multibranched, especially near stem base (simple in Cardaria) |
| |
| | 11. Upper cauline leaves clasping stem |
| |
| | 12. Fruit dehiscent, generally > 4-seeded; inflorescence generally not flat-topped, longer than wide |
| CAMELINA (no key) |
| | 12' Fruit ± indehiscent, 2–4-seeded; inflorescence ± flat-topped, wider than long |
| CARDARIA |
| | 11' Upper cauline leaves 0 or not clasping stem |
| |
| | 13. Herbage hairs mostly stellate; seeds generally 2+ per chamber |
| |
| LESQUERELLA |
| | 14' Fruit tip (and often base) ± deeply notched |
| PHYSARIA (no key) |
| | 13' Herbage hairs mostly simple or multibranched; seed generally 1 per chamber |
| |
| | 15. Leaves generally ± basal, < 5 mm wide; fruit not beaked |
| CUSICKIELLA |
| | 15' Leaves cauline, often > 10 mm wide; fruit beak stout |
| EUCLIDIUM (no key)
|