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arrow thelypody, slender thelypody

Howell's thelypody

Habit Biennials or perennials; (short-lived); sometimes glaucous, glabrous throughout or sparsely to densely pubescent. Biennials or, rarely, perennials; (short-lived); glaucous, glabrous (except petioles).
Stems

branched often proximally and distally, (2–)3–8(–12.5) dm, (glabrous or pubescent).

branched distally, 1–8(–9.3) dm.

Basal leaves

petiole (1–)2–8(–14) cm, ciliate;

blade usually oblanceolate to ovate, rarely oblong, (2–)6.5–20(–29) cm × 10–42(–50) mm, margins entire, (surfaces glabrous or pubescent).

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.

Cauline leaves

(ascending);

sessile;

blade lanceolate to oblong-lanceolate, (0.8–)1.6–8.5(–14) cm × 2–13(–28) mm, (base amplexicaul to sagittate), margins entire, (surfaces glabrous or pubescent).

(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.

Racemes

sometimes corymbose, lax or dense, elongated or not in fruit, (flower buds ovate to lanceolate).

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

Flowers

sepals erect, ovate to oblong, (2.5–)3–6(–10) × (1–)1.5–2(–2.5) mm;

petals white or lavender to purple, oblanceolate to spatulate or linear, (5–)7–14(–19) × (0.5–)1–3(–4) mm, margins slightly crisped between blade and claw, claw differentiated from blade, [slender, (2–)3–6.5(–10) mm, narrowest at base];

nectar glands confluent and subtending bases of stamens, sometimes only lateral;

filaments tetradynamous, median pairs 3–5.5(–8) mm, lateral pair (2–)2.5–4.5(–7) mm;

anthers included or partially exserted, oblong, (1.5–)2–3.2(–5) mm, not circinately coiled;

gynophore (stout), 0.5–1(–2) mm.

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.

Fruiting pedicels

horizontal to divaricate, often curved upward, stout or slender, (2.5–)3.5–11(–20) mm, not flattened at base.

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

Fruits

erect, torulose, straight or slightly incurved (forming arc with pedicel), usually terete, rarely 4-angled, 1–5.3(–6.9) cm × (0.5–)0.8–1(–1.2) mm;

ovules 20–62per ovary;

style cylindrical, 0.5–1.5(–3.3) mm.

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.

Seeds

(flattened), (0.7–)1–1.3(–1.5) × 0.5–0.7(–1) mm.

(1–)1.2–1.7(–2) × 0.5–0.7 mm.

Thelypodium sagittatum

Thelypodium howellii

Distribution
from FNA
CO; ID; MT; NV; UT; WA; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; OR; WA
[WildflowerSearch map]
[BONAP county map]
Discussion

Subspecies 2 (2 in the flora).

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

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.)

Key
1. Racemes often dense; fruiting pedicels 5-11(-20) mm; petals spatulate to oblanceolate, 1-3(-4) mm wide; median nectar glands often absent.
subsp. sagittatum
1. Racemes lax; fruiting pedicels (2.5-)3.5-7(-8) mm; petals linear to linear-oblanceolate, 0.5-1 (-1.5) mm wide; median nectar glands present.
subsp. ovalifolium
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. 736. FNA vol. 7, p. 732.
Parent taxa Brassicaceae > tribe Thelypodieae > Thelypodium Brassicaceae > tribe Thelypodieae > Thelypodium
Sibling taxa
T. brachycarpum, T. crispum, T. eucosmum, T. flexuosum, T. howellii, T. integrifolium, T. laciniatum, T. laxiflorum, T. milleflorum, T. paniculatum, T. repandum, T. rollinsii, T. stenopetalum, T. texanum, T. wrightii
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
Subordinate taxa
T. sagittatum subsp. ovalifolium, T. sagittatum subsp. sagittatum
T. howellii subsp. howellii, T. howellii subsp. spectabilis
Synonyms Streptanthus sagittatus, Pachypodium sagittatum, Thelypodiopsis nuttallii, Thelypodiopsis sagittata, Thelypodiopsis torulosa, T. nuttallii, T. torulosum Cartiera howellii, Thelypodiopsis howellii
Name authority (Nuttall) Endlicher: in W. G. Walpers, Repert. Bot. Syst. 1: 172. (1842) S. Watson: Proc. Amer. Acad. Arts 21: 445. (1886)
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