Rorippa microtitis

(B. L. Robinson) Rollins

Rhodora 59: 71. 1957.

Basionym: Sisymbrium microtitis B. L. Robinson Bot. Gaz. 30: 59. 1900
Synonyms: Nasturtium microtitis (B. L. Robinson) O. E. Schulz
Treatment appears in FNA Volume 7. Treatment on page 501. Mentioned on page 496.

Annuals or, rarely, biennials; usually glabrous throughout, rarely sparsely pubescent proximally. Stems (simple or few from base), erect, branched distally, 1.5–6 dm. Basal leaves often not rosulate; blade margins pinnatifid. Cauline leaves petiolate; blade pinnatifid to pinnatisect or pectinate, (lobes 4–10 on each side, linear or oblong to ovate), 4–13 cm × 9–35 mm; base auriculate, margins entire or dentate, or (distally) pinnately lobed. Racemes (subumbellate), considerably elongated. Fruiting pedicels divaricate-ascending to horizontal, straight, 3–11 mm. Flowers: sepals ascending to spreading, oblong, 2–3 × 0.7–1 mm; petals (spreading), yellow, spatulate, 2.5–4 × 0.7–1.2mm; median filaments 1.8–3 mm; anthers oblong, 0.5–0.8 mm. Fruits siliques, usually curved inward, rarely straight, linear, (8–)10–17(–20) × 1–2 mm; ovules 42–68 per ovary; style 0.5–1(–1.2) mm. Seeds biseriate, reddish brown, cordiform, 0.6–0.9 mm (0.5–0.6 mm diam.), reticulate-foveolate.


Phenology: Flowering Jun–Aug.
Habitat: Wet pastures, moist fields, ponds, ditches, meadows
Elevation: 1700-2300 m

Distribution

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Ariz., N.Mex., Mexico (Chihuahua).

Discussion

Selected References

None.

Lower Taxa

None.