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Rollins' twinpod

foothill bladderpod, silver bladderpod

Habit Perennials; (compact); caudex usually simple, (cespitose); (silvery) pubescent throughout, trichomes 6–8-rayed, rays furcate near base, fused at base, (umbonate, strongly tuberculate throughout). Perennials; caudex simple or branched; densely pubescent, trichomes (sessile or short-stalked), 4–7-rayed, rays usually furcate, sometimes bifurcate, (rough-tuberculate throughout).
Stems

several from base, decumbent, (unbranched, slender), 0.5–1 dm.

few from base, erect with outer usually decumbent, 1–3.5(–5) dm.

Basal leaves

(strongly rosulate);

blade usually oblanceolate or broader, sometimes triangular, 2–3.5 cm (width 5–10 mm), margins entire or with 1 or 2 broad teeth, (apex acute).

(erect);

blade narrowly lanceolate to linear or (outer) oblanceolate, (1–)2–6(–9) cm, margins usually entire, rarely shallowly dentate, (inner involute, outer usually flat, base usually with some simple trichomes).

Cauline leaves

blade oblanceolate, 1–1.5 cm (width 2–4 mm), margins entire, (apex acute).

blade narrowly oblanceolate to linear, (1–)2–4(–8) cm, margins flat or involute.

Racemes

congested, (elongated moderately in fruit).

compact, (elongated and loose in fruit, densely-flowered).

Flowers

sepals linear, 5–7 mm;

petals spatulate, 8–10 mm, (apex often somewhat truncate).

sepals oblong to broadly elliptic, 4–7(–8) mm, (lateral pair subsaccate, median pair cucullate);

petals oblanceolate or obovate, (5–)6.5–9.5(–11) mm, (claw undifferentiated from blade, or blade gradually narrowed to claw).

Fruiting pedicels

(spreading, straight or somewhat sigmoid), 5–8 mm.

(usually recurved), (5–)10–20(–25) mm.

Fruits

(erect), didymous, suborbicular, inflated, 2–5(–8) × 4–8(–10)mm, (coriaceous, base slightly cordate or nearly obtuse, sinus obsolete or absent, apical sinus broad and deep);

valves (retaining seeds after dehiscence), pubescent, trichomes appressed, (silvery on ovaries and immature fruit);

replum obovate to oblong, as wide as or wider than fruit, rarely somewhat constricted basally, apex obtuse;

ovules 4 per ovary;

style 5–7 mm.

subglobose or obovoid, usually inflated, sometimes slightly compressed, (3–)4–6 mm;

valves densely pubescent, trichomes spreading, usually pubescent inside, trichomes appressed, sessile;

ovules (4–)8–12(–16) per ovary;

style 3–4.5(–6.5) mm.

Seeds

slightly flattened.

slightly flattened.

2n

= 8.

= 10, 20, 30.

Physaria rollinsii

Physaria ludoviciana

Phenology Flowering May–Jun. Flowering Apr–Jul(-Aug).
Habitat Sagebrush, granitic talus, open knolls, limestone chiprock, steep slopes, clay banks, near granite boulders Sandy or gravelly soils, steep hillsides, prairie pastures, clay slopes, limestone outcrops, sand dunes, open plains, sandy bluffs, rocky flats, white tuff sands
Elevation 2300-2500(-3900) m (7500-8200(-12800) ft) 0-1900 m (0-6200 ft)
Distribution
from FNA
CO
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CA; CO; IA; IL; KS; MN; MT; ND; NE; NM; NV; OK; SD; UT; WI; WY
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[BONAP county map]
Discussion

Material previously reported as Physaria ludoviciana from Canada (Alberta, Manitoba, Saskatchewan) is here included in 6a. P. arenosa subsp. arenosa. Lesquerella argentea (Pursh) MacMillan is a later homonym that has been used for P. ludoviciana.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 7, p. 661. FNA vol. 7, p. 649.
Parent taxa Brassicaceae > tribe Physarieae > Physaria Brassicaceae > tribe Physarieae > Physaria
Sibling taxa
P. acutifolia, P. alpestris, P. alpina, P. angustifolia, P. arctica, P. arenosa, P. argyraea, P. arizonica, P. aurea, P. bellii, P. brassicoides, P. calcicola, P. calderi, P. carinata, P. chambersii, P. cinerea, P. condensata, P. congesta, P. cordiformis, P. curvipes, P. densiflora, P. didymocarpa, P. dornii, P. douglasii, P. eburniflora, P. engelmannii, P. eriocarpa, P. fendleri, P. filiformis, P. floribunda, P. fremontii, P. garrettii, P. geyeri, P. globosa, P. gooddingii, P. gordonii, P. gracilis, P. grahamii, P. hemiphysaria, P. hitchcockii, P. humilis, P. integrifolia, P. intermedia, P. kingii, P. klausii, P. lata, P. lepidota, P. lesicii, P. lindheimeri, P. ludoviciana, P. macrocarpa, P. mcvaughiana, P. montana, P. multiceps, P. navajoensis, P. nelsonii, P. newberryi, P. obcordata, P. obdeltata, P. occidentalis, P. oregona, P. ovalifolia, P. pachyphylla, P. pallida, P. parviflora, P. parvula, P. pendula, P. pinetorum, P. prostrata, P. pruinosa, P. pulvinata, P. purpurea, P. pycnantha, P. rectipes, P. recurvata, P. reediana, P. saximontana, P. scrotiformis, P. sessilis, P. spatulata, P. subumbellata, P. tenella, P. thamnophila, P. tumulosa, P. valida, P. vicina, P. vitulifera
P. acutifolia, P. alpestris, P. alpina, P. angustifolia, P. arctica, P. arenosa, P. argyraea, P. arizonica, P. aurea, P. bellii, P. brassicoides, P. calcicola, P. calderi, P. carinata, P. chambersii, P. cinerea, P. condensata, P. congesta, P. cordiformis, P. curvipes, P. densiflora, P. didymocarpa, P. dornii, P. douglasii, P. eburniflora, P. engelmannii, P. eriocarpa, P. fendleri, P. filiformis, P. floribunda, P. fremontii, P. garrettii, P. geyeri, P. globosa, P. gooddingii, P. gordonii, P. gracilis, P. grahamii, P. hemiphysaria, P. hitchcockii, P. humilis, P. integrifolia, P. intermedia, P. kingii, P. klausii, P. lata, P. lepidota, P. lesicii, P. lindheimeri, P. macrocarpa, P. mcvaughiana, P. montana, P. multiceps, P. navajoensis, P. nelsonii, P. newberryi, P. obcordata, P. obdeltata, P. occidentalis, P. oregona, P. ovalifolia, P. pachyphylla, P. pallida, P. parviflora, P. parvula, P. pendula, P. pinetorum, P. prostrata, P. pruinosa, P. pulvinata, P. purpurea, P. pycnantha, P. rectipes, P. recurvata, P. reediana, P. rollinsii, P. saximontana, P. scrotiformis, P. sessilis, P. spatulata, P. subumbellata, P. tenella, P. thamnophila, P. tumulosa, P. valida, P. vicina, P. vitulifera
Synonyms Alyssum ludovicianum, Lesquerella ludoviciana, Vesicaria ludoviciana
Name authority G. A. Mulligan: Canad. J. Bot. 44: 1663, fig. 2, plate 1, fig. 4. (1966) (Nuttall) O’Kane & Al-Shehbaz: Novon 12: 325. (2002)
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