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roundtip twinpod

Snake River or creeping twinpod, Snake River twinpod

Habit Perennials; caudex simple or branched, (cespitose); (silvery) pubescent throughout, trichomes several-rayed, rays furcate or bifurcate, (relatively massive, smooth to few-tubercled). Perennials; caudex usually branched, (rhizomelike, cespitose); densely (silvery) pubescent, trichomes (often stalked, appressed), several-rayed, rays furcate or bifurcate, (umbonate, strongly tuberculate throughout).
Stems

several from base, usually decumbent to ascending, (arising laterally, unbranched, coarse), 1–2 dm.

several from base, ± erect, exceeding basal rosette by ± 0.5 dm.

Basal leaves

blade pandurate or obovate, 3–6 cm, margins usually deeply and broadly incised, rarely subentire, (apex obtuse).

(forming a strong rosette; long-petiolate);

blade oblanceolate to ovate or orbicular, (1.5–)2–4(–8) cm, (base usually abruptly tapering to petiole), margins entire.

Cauline leaves

blade oblanceolate to spatulate, similar to basal, (3–6 mm wide), margins entire, (apex often somewhat acute).

blade oblanceolate, 1–2 cm, margin entire, (apex acute).

Racemes

congested, (elongated in fruit).

congested, (greatly exceeding leaves).

Flowers

sepals oblong, 6–8 mm;

petals spatulate, to 10 mm.

sepals often keeled, 6–8 mm;

petals spatulate, 8–10 mm.

Fruiting pedicels

(usually curving upward, sigmoid), 6–10 mm.

(spreading, straight or slightly curved), 7–11 mm.

Fruits

didymous, irregular in shape, somewhat angular, inflated, 5–7 × 6–8 mm, (papery, often rigid, base obtuse or truncate, apical sinus broad, open and deep);

valves (retaining seeds after dehiscence), pubescent, trichomes spreading, loose;

replum oblong, often constricted, as wide as or wider than fruit, apex obtuse;

ovules 4 per ovary;

style 5–7 mm.

didymous, highly inflated, 8–22 × 10–25 mm, (papery, basal and apical sinuses deep);

valves (retaining seeds after dehiscence), densely pubescent, trichomes appressed;

replum linear to oblong, as wide as or wider than fruit;

ovules 8 per ovary;

style 7–9 mm.

Seeds

flattened.

flattened.

2n

= 8, 16.

= 16.

Physaria vitulifera

Physaria integrifolia

Phenology Flowering Apr–Jun. Flowering (May-)Jun–Jul(-Aug).
Habitat Rocky hillsides, dry banks, gravel and sand, granitic slopes, soil scree, red shale Calcareous hills and slopes, shale-limestone cliffs, bare steep slopes, red clay banks, shale
Elevation 1600-3000 m (5200-9800 ft) 1900-2700 m (6200-8900 ft)
Distribution
from FNA
CO
[WildflowerSearch map]
[BONAP county map]
from FNA
ID; MT; WY
[BONAP county map]
Discussion

Physaria integrifolia has traditionally been recognized as a variety of P. didymocarpa, but it is morphologically and ecologically quite distinctive. Variety monticola (no combination has been made at subspecific rank) is not recognized here; it is considered another example, in the genus, of caudices elongating in response to shifting substrates.

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

Source FNA vol. 7, p. 665. FNA vol. 7, p. 644.
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. rollinsii, P. saximontana, P. scrotiformis, P. sessilis, P. spatulata, P. subumbellata, P. tenella, P. thamnophila, P. tumulosa, P. valida, P. vicina
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. 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 P. didymocarpa var. integrifolia, P. integrifolia var. monticola
Name authority Rydberg: Bull. Torrey Bot. Club 28: 278. (1901) (Rollins) Lichvar: Madroño 31: 203. (1984)
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