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common twinpod, double twinpod, twin bladderpod

Arizona 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). Perennials; caudex branched, (cespitose); densely (silvery gray) pubescent, trichomes (sessile or subsessile), (4-), 6-, or 8-rayed, rays fused at base, furcate or bifurcate, (slightly umbonate, tuberculate throughout).
Stems

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

simple or few to several from base, erect, (unbranched, slender), 0.2–1(–1.5) dm.

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).

(densely tufted, not rosulate, reflexed in age);

blade obovate to oblanceolate, 0.7–2(–3) cm, margins usually entire, sometimes repand or shallowly dentate, (apex acute).

Cauline leaves

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

similar to basal, becoming narrower distally, somewhat reflexed, (distal) blade linear or narrowly oblanceolate, 0.5–2.5(–5.5) cm.

Racemes

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

dense, often subcorymbiform.

Flowers

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

petals spatulate, 10–12 mm.

sepals (green or greenish yellow), ovate or broadly ovate, 3.5–6.5 mm, (lateral pair subsaccate, cucullate, median pair thickened, slightly cucullate apically);

petals (spreading), oblanceolate to obovate, 5.5–8(–10) mm, (claw erect).

Fruiting pedicels

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

(erect or divaricate-spreading, straight or slightly curved), (3–)5–10(–15) 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), suborbicular to ovoid or ellipsoid, slightly inflated, 4–7 mm;

valves pubescent outside, trichomes substipitate, spreading, sometimes sparsely pubescent inside, trichomes sessile, smooth;

ovules 4–10(–16) per ovary;

style (0.5–)1–2(–4) mm (shorter than fruit).

Seeds

flattened.

flattened.

2n

= 10.

Physaria didymocarpa

Physaria arizonica

Phenology Flowering Apr–Jun.
Habitat Sandy and gravelly soils, limey knolls or limestone chip, often in open stands of sagebrush-pinyon, pinyon-juniper, Gambel oak and sometimes ponderosa pine
Elevation 1000-2200 m (3300-7200 ft)
Distribution
from FNA
ID; MT; WA; WY; AB; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; UT
[WildflowerSearch map]
[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.)

The circumscription of Physaria arizonica here is quite broad and includes plants that have densely tufted basal leaves and relatively few or no cauline leaves; plants that are loosely tufted and have several cauline leaves; and plants that have a strongly branched caudex, leafy stems, and sterile shoots (var. andrusensis). Additional study is needed to understand the pattern of variation in this complex species; all of the characters given above vary considerably.

(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. 627.
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. 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
Subordinate taxa
P. didymocarpa subsp. didymocarpa, P. didymocarpa subsp. lanata, P. didymocarpa subsp. lyrata
Synonyms Vesicaria didymocarpa, Coulterina didymocarpa Lesquerella arizonica, Lesquerella arizonica var. nudicaulis, P. arizonica var. andrusensis
Name authority (Hooker) A. Gray: Gen. Amer. Bor. 1: 162. (1848) (S. Watson) O’Kane & Al-Shehbaz: Novon 12: 321. (2002)
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