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common twinpod, double twinpod, twin bladderpod

spreading 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). Annuals or biennials; (delicate, wiry); with a fine taproot; pubescent, trichomes (sessile or subsessile), 4–7-rayed, rays distinct, usually furcate, occasionally bifurcate, (smooth to somewhat tuberculate).
Stems

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

simple to several from base, erect, often outer decumbent, (unbranched or branched distally), 1–7 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).

blade oblanceolate to elliptic, 1.5–8(–11.5) cm, margins lyrate-pinnatifid to dentate or repand, (abaxial surface densely pubescent, adaxial sparsely pubescent).

Cauline leaves

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

(proximal petiolate, distal sessile);

blade oblanceolate to oblong, 1–7 cm, margins dentate to repand.

Racemes

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

loose, (elongated).

Flowers

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

petals spatulate, 10–12 mm.

sepals elliptic or broadly ovate, 3–6.5(–8) mm, (median pair slightly thickened apically, cucullate);

petals (yellow to orange), broadly obovate, 6–11 mm, (narrowing gradually to short claw).

Fruiting pedicels

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

(usually divaricate-spreading, sometimes horizontal or shallowly recurved, straight or slightly curved), (7–)10–20(–25) mm, (slender or stout).

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.

(stipitate or subsessile, gynophore 1–2 mm), globose, subglobose, obpyriform, or obovoid, not or slightly inflated, 3–9 mm;

valves (not retaining seeds after dehiscence), glabrous throughout or sparsely pubescent inside;

replum as wide as or wider than fruit;

ovules 8–20(–28) per ovary;

style 2–4.5 mm.

Seeds

flattened.

slightly flattened.

Physaria didymocarpa

Physaria gracilis

Distribution
from FNA
ID; MT; WA; WY; AB; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; IA; IL; KS; LA; MO; MS; OK; TN; TX
[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.)

Subspecies 2 (2 in the flora).

(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
1. Stems to 7 dm; cauline leaves: blade margins usually deeply dentate, rarely repand; fruits ± sessile, globose or subglobose, 3-6 mm, bases rounded.
subsp. gracilis
1. Stems usually less than 3 dm; cauline leaves: blade margins frequently repand, occasionally dentate; fruits stipitate (gynophore slender), obpyriform to narrowly obovoid, (5-)6-9 mm, bases truncate.
subsp. nuttallii
Source FNA vol. 7, p. 633. FNA vol. 7, p. 641.
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. globosa, P. gooddingii, P. gordonii, 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
P. gracilis subsp. gracilis, P. gracilis subsp. nuttallii
Synonyms Vesicaria didymocarpa, Coulterina didymocarpa Vesicaria gracilis, Alyssum gracile, Lesquerella gracilis
Name authority (Hooker) A. Gray: Gen. Amer. Bor. 1: 162. (1848) (Hooker) O’Kane & Al-Shehbaz: Novon 12: 323. (2002)
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