Flora of North America species comparison

The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Acmispon strigosus

Acmispon rubriflorus

strigose lotus

red-flower bird's-foot trefoil, red-flower deervetch or trefoil
Habit Herbs, annual, usually mat-forming, sometimes cespitose (ascending and bushy), green to grayish, 0.3–5 dm, not or ± fleshy, strigillose, hirsute, canescent-tomentose, or scantily pubescent; taprooted. Herbs, annual, cespitose, greenish, 0.4–0.9 dm, not fleshy, villous; taprooted.
Stems

1–20+, procumbent or decumbent to ascending, branched basally, herbaceous, slender, leafy.

1–5+, decumbent to ascending, branched basally, herbaceous, leafy.
Leaves

irregularly pinnate;

stipules glandlike;

subsessile;

rachis 3–20 mm, flattened;

leaflets 4–10, blades unequal, obovate to oblanceolate to linear-oblong or oblong, apex acute to obtuse or truncate, surfaces ± densely tomentose to glabrate.

irregularly pinnate or palmate;

stipules glandlike, barely visible;

subsessile;

rachis 4–6 mm, flattened;

leaflets 4, 2 on one side and 2 terminal, blades lanceolate, sometimes asymmetric apex acute, surfaces villous.
Inflorescences

1–3-flowered.

1-flowered.
Peduncles

ascending or reflexed, upturned, 3–25 mm, shorter to longer than leaves (often elongated in fruit);

bract absent or 1–3-foliolate, usually subtending umbel.

± sessile;

bract absent.
Flowers

(5–)6–10(–12) mm;

calyx 3–5.5 mm, tube ± sparsely strigillose or glabrous, lobes subulate;

corolla yellow (sometimes banner orangish abaxially), turning orange or reddish, claws ± equaling calyx tube, banner implicate-ascending or remaining closely implicate, wings longer than keel;

style corneously thickened, marked by color, straight, puberulent or glabrous.

5–8 mm;

calyx 1.5–5 mm, tube villous, lobes subulate, acuminate;

corolla bright pinkish red, claws shorter than calyx tube, banner implicate-ascending, wings ± equaling keel;

style curved or geniculate, glabrous.
Legumes

persistent, exserted, erect or divergent, brown, straight to ± curved distally, compressed, not or slightly constricted, incompletely septate, linear-oblong, 10–35 × 2–3 mm, thinly leathery, apex initially short-beaked, dehiscent, smooth, margins smooth, thin, glabrous or ± strigose.

persistent, mostly included, erect, stramineous, straight, compressed, slightly constricted, not septate, broadly oblong, 8–9 × 2.5 mm, papery, apex obtuse, dehiscent, smooth, margins smooth, keeled, villous.
Seeds

5–10, greenish to brown, ± mottled, ovoid to cuboid or globose, rugulose or granular.

2–4, olive green to brownish, ± mottled, ± lenticular, semilustrous, smooth to rugose.

Acmispon strigosus

Acmispon rubriflorus
Phenology Flowering spring.
Habitat Open, oak woodlands, grasslands.
Elevation 100–500 m. (300–1600 ft.)
Distribution
sw United States; n Mexico
[BONAP county map]
from FNA
CA
[BONAP county map]
Discussion

Varieties 3 (3 in the flora).

D. Isely (1981) discussed the variation in Acmispon strigosus (as Lotus), distinguishing three varieties, two rather distinct but with intergrading phases, and one apparently more transitional, although distinct enough to be recognized. These varieties were only noted for California in recent treatments (for example, L. Brouillet 2012, following D. Isely 1993). Nonetheless, the typical (for example, excluding intergrading phases) varieties represent recognizable morphologies that also have geographic distinction. Specimens representing intergradation seem to occur throughout the range of overlap of these varieties, sometimes rendering determination difficult.

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

Acmispon rubriflorus is known only from Colusa, Stanislaus, and Tehama counties.

(Discussion copyrighted by Flora of North America; reprinted with permission.)
Key
1. Herbs evidently hirsute, especially at apex, greenish.
var. hirtellus
1. Herbs usually strigillose or canescent-tomentose to scantly pubescent, rarely strigillose, green or cinereous.
→ 2
2. Stems ascending or decumbent, not markedly succulent, usually appearing green, sometimes cinereous; leaflet blades linear-oblong, apices acute to obtuse; corolla opening; California.
var. strigosus
2. Stems prostrate, succulent, cinereous(–greenish); leaflet blades oblong, apices obtuse or truncate; corolla not opening; Arizona, California, Nevada.
var. tomentellus
Source FNA vol. 11. FNA vol. 11.
Parent taxa Fabaceae > subfam. Faboideae > Acmispon Fabaceae > subfam. Faboideae > Acmispon
Sibling taxa
A. americanus, A. argophyllus, A. argyraeus, A. brachycarpus, A. cytisoides, A. decumbens, A. dendroideus, A. denticulatus, A. glaber, A. grandiflorus, A. haydonii, A. intricatus, A. junceus, A. maritimus, A. mearnsii, A. micranthus, A. neomexicanus, A. parviflorus, A. plebeius, A. procumbens, A. prostratus, A. rigidus, A. rubriflorus, A. tomentosus, A. utahensis, A. wrangelianus, A. wrightii
A. americanus, A. argophyllus, A. argyraeus, A. brachycarpus, A. cytisoides, A. decumbens, A. dendroideus, A. denticulatus, A. glaber, A. grandiflorus, A. haydonii, A. intricatus, A. junceus, A. maritimus, A. mearnsii, A. micranthus, A. neomexicanus, A. parviflorus, A. plebeius, A. procumbens, A. prostratus, A. rigidus, A. strigosus, A. tomentosus, A. utahensis, A. wrangelianus, A. wrightii
Subordinate taxa
A. strigosus var. hirtellus, A. strigosus var. strigosus, A. strigosus var. tomentellus
Synonyms Hosackia strigosa, Anisolotus strigosus, Lotus strigosus, Ottleya strigosa Lotus rubriflorus
Name authority (Nuttall) Brouillet: J. Bot. Res. Inst. Texas 2: 392. (2008) (Sharsmith) D. D. Sokoloff: Ann. Bot. Fenn. 37: 130. (2000)
Web links 
Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).



Type/paste one or more Latin names into the boxes above; matching taxa will show up below the box as you type. You can use the up/down arrow keys to move through the list.

(If the plant you're looking for doesn't show up in the auto-complete list, that means it either isn't described in Flora of North America yet, or it's listed under a synonym. And please note that Flora of North America is still missing several plant families, including Fabaceae, Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America

The species comparison tool is brought to you by:
Northwest Wildflowers