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common twinpod, double twinpod, twin bladderpod

globe bladderpod

Habit Perennials; caudex branched, (cespitose); densely pubescent, trichomes (often stalked, appressed to wavy and spreading), several-rayed, rays furcate or simple, (slightly to strongly umbonate, nearly smooth to strongly tuberculate). Biennials or perennials; caudex branched, (± woody); densely pubescent, trichomes (sessile), 3–6-rayed, rays distinct and simple or furcate, (in 2 layers, lower layer umbonate, smooth to finely tuberculate, some often with a U-shaped notch).
Stems

several from base, decumbent, (unbranched, leafy for the genus), ca. 1 dm.

several from base, erect, (arising among leaves of an elongated main axis), to 5 dm (± equal).

Basal leaves

(forming a strong rosette; long-petiolate);

blade obovate, 1.5–4(–8) cm, (base ± abruptly narrowing to petiole), margins usually repand or dentate, rarely entire, (apex usually angular, surfaces silvery).

(shortly petiolate);

blade obovate to oblanceolate, (1.5–)2.5–5(–6) cm, margins entire, sinuate to shallowly toothed, or pinnatifid.

Cauline leaves

blade oblanceolate, 1–2 cm (width 4–8 mm), margins entire or with occasional tooth, (apex acute).

(sessile or shortly petiolate);

blade oblanceolate to oblong, 1.3–3(–4) cm, (base cuneate), margins entire or repand to dentate.

Racemes

congested, (elongated in fruit, greatly exceeding leaves).

dense.

Flowers

sepals lanceolate to oblong, 6–8 mm, (often keeled);

petals spatulate, 10–12 mm.

sepals elliptic or obovate, 2.6–4.1 mm, (median pair thickened apically, cucullate);

petals (bright yellow), obovate, 3.5–6.5(–7.5) mm, (margins sinuate).

Fruiting pedicels

(spreading, straight or slightly curved), 8–12 mm.

(usually spreading horizontally, straight), 7–14(–21) mm.

Fruits

(erect), didymous, inflated, 10–20 × 10–20 mm, (papery or firm, basal sinus shallow to deep, sometimes barely notched, apical sinus deep, narrow, usually closed);

valves (retaining seeds after dehiscence), loosely pubescent, trichomes spreading (appearing fuzzy);

replum obovate to broadly oblong, not constricted, 3–4 mm, as wide as or wider than fruit, apex obtuse;

ovules (4–)8 per ovary;

style 7–9 mm.

(sessile or substipitate);

globose, often slightly compressed apically, (1–)2–3 mm;

valves sparsely pubescent, sometimes pubescent inside, trichomes spreading, 3–5-rayed;

ovules 4 per ovary;

style 2–3.5(–4) mm.

Seeds

flattened.

flattened or plump, (often outer surface hemispherical, inner surface flattened, or both surfaces rounded).

2n

= 14.

Physaria didymocarpa

Physaria globosa

Phenology Flowering Mar–May.
Habitat Open rocky areas, shale at cliff bases, open talus, ledges, open cedar glades
Elevation 100-300 m (300-1000 ft)
Distribution
from FNA
ID; MT; WA; WY; AB; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
IN; KY; TN
[BONAP county map]
Discussion

Subspecies 3 (3 in the flora).

The characters used to differentiate Physaria didymocarpa from P. saximontana (especially subsp. dentata) appear to be weak at best: whether there are 4 or 8 ovules per ovary and whether the silicle lacks a basal sinus or one is present. There appears to be intergradation in each of those characters. A traditional circumscription of these species is followed here. Further work is needed at both the species and subspecies level in these taxa.

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

Of conservation concern.

Physaria globosa is possibly introduced in Indiana. A report for Ohio was based on a collection by “Jones,” but that specimen cannot be located.

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

Key
1. Trichomes spreading throughout; basal leaf blade margins dentate.
subsp. lanata
1. Trichomes appressed (except fruits in subsp. didymocarpa); basal leaf blade margins repand to dentate, ± lyrate or, rarely, entire
→ 2
2. Fruits moderately inflated, trichomes spreading.
subsp. didymocarpa
2. Fruits highly inflated (papery), trichomes appressed.
subsp. lyrata
Source FNA vol. 7, p. 633. FNA vol. 7, p. 639.
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. 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. 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
Subordinate taxa
P. didymocarpa subsp. didymocarpa, P. didymocarpa subsp. lanata, P. didymocarpa subsp. lyrata
Synonyms Vesicaria didymocarpa, Coulterina didymocarpa Vesicaria globosa, Alyssum globosum, Alyssum shortii, Lesquerella globosa
Name authority (Hooker) A. Gray: Gen. Amer. Bor. 1: 162. (1848) (Desvaux) O’Kane & Al-Shehbaz: Novon 12: 323. (2002)
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