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Rollins' twinpod

arctic 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, (woody, cespitose); ± densely pubescent, trichomes (sessile or short-stalked), several-rayed, rays distinct, furcate or bifurcate, (somewhat umbonate, finely tuberculate to ± smooth).
Stems

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

simple or few to several from base, erect to spreading or prostrate, 0.5–2(–3) 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).

(usually ± rosulate);

blade obovate to oblanceolate, (1–)2–6(–15) cm, margins entire.

Cauline leaves

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

(sessile or shortly petiolate);

blade oblanceolate or lingulate, 0.5–1.5(–3) cm, margins entire.

Racemes

congested, (elongated moderately in fruit).

loose.

Flowers

sepals linear, 5–7 mm;

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

sepals ovate to elliptic, (3–)4–5(–6) mm, (median pair often thickened apically, cucullate);

petals spatulate, 5–6(–7) mm, (blade gradually narrowed to claw).

Fruiting pedicels

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

(erect to divaricate or ascending), (5–)10–20(–40) mm, (stout).

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 to ellipsoid, uncompressed, 4–6(–9) mm;

valves (not retaining seeds after dehiscence), glabrous or sparsely pubescent outside, trichomes sessile;

replum as wide as or wider than fruit;

ovules (8–)10–14(–16) per ovary;

style 1–2.5(–4) mm.

Seeds

slightly flattened.

plump.

2n

= 8.

= 60.

Physaria rollinsii

Physaria arctica

Phenology Flowering May–Jun. Flowering May–Aug.
Habitat Sagebrush, granitic talus, open knolls, limestone chiprock, steep slopes, clay banks, near granite boulders Typically on sand and gravel from calcareous bedrock, river bars and terraces, cliff ledges, scree and talus slopes, often growing after disturbance
Elevation 2300-2500(-3900) m (7500-8200(-12800) ft) 0-1800 m (0-5900 ft)
Distribution
from FNA
CO
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; AB; BC; MB; NL; NT; NU; QC; YT; Greenland; circumarctic (except n Europe, ne Russia)
[BONAP county map]
Source FNA vol. 7, p. 661. FNA vol. 7, p. 626.
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. 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. 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 arcticum, Lesquerella arctica, Lesquerella arctica subsp. purshii, Vesicaria arctica, Vesicaria leiocarpa
Name authority G. A. Mulligan: Canad. J. Bot. 44: 1663, fig. 2, plate 1, fig. 4. (1966) (Wormskjöld ex Hornemann) O’Kane & Al-Shehbaz: Novon 12: 321. (2002)
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