The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

double bladderpod, pointleaf twinpod, Rydberg's twinpod, sharpleaf twinpod

silver twinpod, west silver bladderpod

Habit Perennials; caudex branched, (sometimes forming a thick crown, cespitose); (silvery) pubescent throughout, trichomes several-rayed, rays furcate, (moderately tuberculate, rays weakly so). Perennials; (diminutive); caudex simple or branched, (buried, with thatch of persistent leaf bases distally); (appearing silvery gray-green to silvery purple), densely pubescent, trichomes usually 5 or 6 (rarely 7)-rayed, rays bifurcate or incompletely so, (relatively short, stout, umbonate, moderately tuberculate to nearly smooth, lower layer smoother).
Stems

several from base, usually somewhat decumbent, (unbranched), (0.4–)0.5–2 dm.

1–5 from base, prostrate to slightly decumbent, (arising laterally, also erect or ascending from tuft of basal leaves, unbranched, purple-green), 0.08–0.3 dm.

Basal leaves

(petiole slender, often narrowly winged);

blade obovate to orbicular or rhombic-orbicular, 2–9 cm, (base abruptly narrowed to petiole), margins usually entire, rarely with few scattered teeth, (apex rounded or obtuse, sometimes with apical mucro).

(petiole slightly winged);

blade oblanceolate, elliptic, or rhombic, (mostly flat, sometimes somewhat folded), 0.6–2.7 cm, (base tapering to petiole), margins entire, (apex rounded to rounded-acute).

Cauline leaves

blade spatulate to oblanceolate, 1–3 cm, margins entire, (apex usually obtuse).

(3–7, shortly petiolate or sessile);

blade elliptic to oblanceolate, 0.3–0.5 cm, margins entire.

Racemes

loose, (elongated in fruit).

crowded, (ca. 3–7 fruits).

Flowers

sepals linear-oblong, 4–7.5 mm;

petals spatulate, 6–11 mm.

sepals (greenish yellow), linear-triangular, 3.7–5 mm, (lateral pair subsaccate);

petals oblanceolate to narrowly obovate, 4.5–9 mm.

Fruiting pedicels

(divaricate, slightly sigmoid or nearly straight), 6–12 mm.

(ascending, straight), 1.8–3.4 mm.

Fruits

(erect), didymous, suborbicular, inflated, (4–)6–15 × (4–)8–20 mm, (papery, basal and apical sinuses similar, basal rarely shallower, apical deep, narrow and closed or nearly so);

valves retaining seeds after dehiscence, pubescent, trichomes appressed;

replum oblong, constricted, 2–3.5 mm, narrower than fruit, apex obtuse;

ovules (2 or) 4 per ovary;

style 4–6(–9) mm.

(shortly stipitate, purple or greenish purple in age), slightly didymous, ovoid to obpyriform, 3–5 mm (wider than long, base rounded-obtuse, apex rounded, flattened, or slightly emarginate);

valves (inflated, slightly wider than replum), pubescent, trichomes scattered;

replum obovate to orbicular-obdeltate, apex rounded, obtuse, or truncate;

septum complete or medially small-perforate;

ovules 4–6(–8) per ovary;

style 2–3.6 mm.

Seeds

(dark brown), flattened, (2–3 mm).

relatively plump, (ovate to suborbicular, usually rounded on one side, ± flat or concave on the other, not mucilaginous when wetted).

2n

= 10, 16, 24.

Physaria acutifolia

Physaria scrotiformis

Phenology Flowering May–Jun(-Jul). Flowering Jun-early Jul.
Habitat Hillsides, roadcuts, sagebrush, pinyon-juniper, Gambel oak, ponderosa pine communities Tundra areas with islands of Engelmann spruce on Leadville limestone, amidst limestone cobbles and gravel
Elevation 1500-3500 m (4900-11500 ft) 3500-3700 m (11500-12100 ft)
Distribution
from FNA
AZ; CO; ID; MT; NM; NV; SD; UT; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
CO
[BONAP county map]
Discussion

Physaria acutifolia tends to be somewhat dwarfed, with a branched caudex and especially long styles (var. stylosa), where it grows at high elevations, especially at the western end of the Uinta Mountains in Utah. Intermediates form an uninterrupted cline and no infraspecific taxa are here recognized. In R. C. Rollins (1939), the discussion of P. acutifolia actually pertains to P. rollinsii. The discussion of P. australis pertains to what is now known as P. acutifolia. The plants are usually found in open soil patches, rarely into the subalpine or alpine tundra.

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

Physaria scrotiformis is known only from La Plata County.

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

Source FNA vol. 7, p. 624. FNA vol. 7, p. 662.
Parent taxa Brassicaceae > tribe Physarieae > Physaria Brassicaceae > tribe Physarieae > Physaria
Sibling taxa
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. rollinsii, 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. 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. sessilis, P. spatulata, P. subumbellata, P. tenella, P. thamnophila, P. tumulosa, P. valida, P. vicina, P. vitulifera
Synonyms P. acutifolia var. stylosa, P. australis, P. didymocarpa var. australis, P. stylosa
Name authority Rydberg: Bull. Torrey Bot. Club 28: 279. (1901) O’Kane: Novon 17: 376, fig. 1. (2007)
Web links