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Howell's thelypody

arrow-leaf thelypody, world thelypody

Habit Biennials or, rarely, perennials; (short-lived); glaucous, glabrous (except petioles). Biennials or perennials; (short-lived); glaucous, glabrous (except petioles).
Stems

branched distally, 1–8(–9.3) dm.

branched distally, 2–10 dm.

Basal leaves

petiole 0.5–2 cm, ciliate;

blade often oblanceolate to spatulate, sometimes oblong or lanceolate, 2–10(–13.5) cm × 10–23(–40) mm, margins often lyrate to dentate, sometimes entire or repand.

petiole (0.9–)1.4–3(–4.5) cm, ciliate;

blade usually oblanceolate to oblong or lanceolate, rarely ovate or elliptic, (2.8–)3.5–8.8(–11) cm × (7–)10–25(–35) mm, margins often entire or repand, sometimes sinuate.

Cauline leaves

(ascending);

sessile;

blade often lanceolate to linear, sometimes oblong, (0.8–)1–9.7(–14.5) cm × 2–10(–30) mm, (base usually amplexicaul to strongly sagittate, rarely auriculate), margins entire.

(ascending);

sessile;

blade lanceolate to oblong, 1.8–4.5(–6) cm × 5–16(–24) mm, (base amplexicaul to strongly auriculate), margins entire.

Racemes

lax, elongated in fruit, (flower buds ovate to lanceolate).

lax, slightly elongated in fruit, (flower buds oblong-linear).

Flowers

sepals erect, linear or lanceolate, (3.5–)5–8.5(–11.5) × (0.7–)1–2(–2.5) mm;

petals lavender to purple, linear or oblanceolate to spatulate, (6–)9–16.5(–22) × 0.5–2.7(–3) mm, margins partially crisped, claw differentiated from blade, [slender, (2.5–)4–7(–11) mm, narrowest at base];

nectar glands confluent, subtending bases of stamens;

filaments slightly tetradynamous, median pairs (3–)5.5–9(–12) mm, lateral pair (2.5–)4.5–8(–10) mm;

anthers slightly exserted to included, linear, (1.5–)2–4(–5.5) mm, not circinately coiled;

gynophore (stout), 0.5–1(–3.5) mm.

sepals erect, linear-oblong, 5–7(–8) × (0.8–)1–1.5(–1.8) mm;

petals dark purple, spatulate to oblanceolate, (6.6–)7.5–10(–11.5) × 1–1.8(–2) mm, margins not crisped, claw differentiated from blade, [slender, (3–)3.5–5(–5.5) mm, narrowest at base];

nectar glands confluent, subtending bases of stamens;

filaments subequal, (4.5–)6–9(–10) mm;

anthers exserted, linear to narrowly oblong, 2.5–4(–4.5) mm, circinately coiled;

gynophore (1–)2.5–6(–7.5) mm.

Fruiting pedicels

usually ascending, rarely divaricate-ascending, usually straight, rarely slightly incurved, stout, (2.5–)3.5–8(–14.5) mm, not flattened at base.

horizontal to divaricate, usually straight, rarely slightly incurved, slender, (2.5–)3–5.5(–6.5) mm, slightly flattened at base.

Fruits

often ascending, sometimes erect or divaricate, slightly torulose, straight or slightly incurved (forming straight line with pedicel), terete, 1.5–6.5(–8.2) cm × 1–1.3(–2) mm;

ovules 22–40 per ovary;

style cylindrical or subclavate, (0.5–)1–2.7(–4.3) mm.

divaricate to ascending, torulose, straight or slightly incurved, terete, (2–)2.4–5(–6.5) cm × 0.7–1(–1.3) mm;

ovules 44–58 per ovary;

style usually cylindrical, rarely subclavate, 0.5–1.5(–2) mm.

Seeds

(1–)1.2–1.7(–2) × 0.5–0.7 mm.

0.7–1.5 × 0.5–0.8 mm.

Thelypodium howellii

Thelypodium eucosmum

Phenology Flowering May–Jul.
Habitat Shady slopes and canyons, pinyon-juniper and oak woodland communities, stream beds, streamsides
Elevation 700-1000 m (2300-3300 ft)
Distribution
from FNA
CA; OR; WA
[WildflowerSearch map]
[BONAP county map]
from FNA
OR
[WildflowerSearch map]
[BONAP county map]
Discussion

Subspecies 2 (2 in the flora).

Streptanthus howellii (S. Watson) M. E. Jones is a later homonym of S. howellii S. Watson 1885.

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

Of conservation concern.

Thelypodium eucosmum is known only from Baker, Grant, and Wheeler counties. It is in the Center for Plant Conservation’s National Collection of Endangered Plants.

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

Key
1. Petals usually linear to narrowly oblanceolate, rarely spatulate, 0.5-1.2(-3) mm wide; median filaments connate most of their lengths; ne California, c, s Oregon, s Washington.
subsp. howellii
1. Petals usually spatulate, rarely oblanceolate, (1.2-) 1.5-2.7(-3) mm wide; median filaments distinct; e Oregon.
subsp. spectabilis
Source FNA vol. 7, p. 732. FNA vol. 7, p. 731.
Parent taxa Brassicaceae > tribe Thelypodieae > Thelypodium Brassicaceae > tribe Thelypodieae > Thelypodium
Sibling taxa
T. brachycarpum, T. crispum, T. eucosmum, T. flexuosum, T. integrifolium, T. laciniatum, T. laxiflorum, T. milleflorum, T. paniculatum, T. repandum, T. rollinsii, T. sagittatum, T. stenopetalum, T. texanum, T. wrightii
T. brachycarpum, T. crispum, T. flexuosum, T. howellii, T. integrifolium, T. laciniatum, T. laxiflorum, T. milleflorum, T. paniculatum, T. repandum, T. rollinsii, T. sagittatum, T. stenopetalum, T. texanum, T. wrightii
Subordinate taxa
T. howellii subsp. howellii, T. howellii subsp. spectabilis
Synonyms Cartiera howellii, Thelypodiopsis howellii
Name authority S. Watson: Proc. Amer. Acad. Arts 21: 445. (1886) B. L. Robinson: in A. Gray et al., Syn. Fl. N. Amer. 1(1,1): 175. (1895)
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