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Santa Rita Mountain ticktrefoil

Illinois tickclover, Illinois ticktrefoil

Habit Herbs, perennial, diffuse; base woody, rootstock woody. Herbs, perennial.
Stems

erect, ascending, or procumbent, usually striate, 30–60(–100) cm, sparsely to densely pilose and uncinate-pubescent.

ascending to erect, branched or unbranched, 50–100 cm, medially uncinate-pubescent, sometimes also ± pilose.

Leaves

trifoliolate, sometimes unifoliolate proximally;

stipules persistent, recurved, subulate, 2–3 mm;

petiole 7–25 mm;

leaflet blades usually oblong-ovate to narrowly so, sometimes broadly elliptic to oblong, apex obtuse or acute, surfaces sparsely uncinate-puberulent;

terminal blade 10–30(–35) × 8–10 mm, length 1–3.5 times width.

trifoliolate;

stipules persistent, ovate, 8–15 mm, base amplexicaul, pilose-ciliate;

petiole 30–50 mm;

leaflet blades narrowly ovate to ovate, thick, papery, apex acute to rounded, surfaces conspicuously reticulate-veined abaxially, uncinate-puberulent on veins abaxially, sparsely spreading-villous or glabrous adaxially;

terminal blade 35–80 × 30–70 mm, length 1.5–3 times width.

Inflorescences

usually unbranched, sometimes branched;

rachis patent uncinate-puberulent;

primary bracts narrowly ovate, 2.5–3 mm.

usually unbranched;

rachis patent-pilose and uncinate-puberulent;

primary bracts narrowly ovate, 4–5 mm.

Pedicels

8–15 mm.

7–15(–23) mm.

Flowers

calyx 1.5–2.5 mm, pubescent, tube 1 mm;

abaxial lobes 1.5 mm, lateral lobes 1 mm;

corolla pink-purple, 4–5 mm.

calyx 4–5 mm, uncinate-puberulent and pilose, tube 2–3 mm;

abaxial lobes 2.5 mm, lateral lobes 2 mm;

corolla purplish, 6–8 mm.

Loments

sutures subequally crenate;

connections central, 1/5–1/4 as broad as segments;

segments 2–7, rounded or broadly elliptic, 2.5–3 × 2.5 mm, abaxially and adaxially rounded, glabrous or slightly puberulent;

stipe 1–2 mm.

sutures equally crenate;

connections central, 1/2–4/5 as broad as segments;

segments 4–7, elliptic or suborbiculate, 4–7 × 3.5–5 mm, symmetrically convex abaxially and adaxially, densely uncinate-puberulent and villous;

stipe 2–4 mm.

Desmodium retinens

Desmodium illinoense

Phenology Flowering late summer–fall. Flowering summer(–fall).
Habitat Wooded or grassy rocky slopes, oak or oak-pine forests. Prairie relics, thickets, road­sides.
Elevation 1400–2100 m. (4600–6900 ft.) 100–500 m. (300–1600 ft.)
Distribution
from FNA
AZ; Mexico; Central America (Guatemala)
[BONAP county map]
from FNA
AR; IA; IL; IN; KS; MI; MN; MO; NE; OH; OK; SD; TX; WI
[WildflowerSearch map]
[BONAP county map]
Discussion

Desmodium retinens is known in the flora area from Cochise, Graham, Pima, and Santa Cruz counties.

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

Desmodium illinoense is considered extirpated from Ontario, where it was collected once in 1888 near London.

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

Source FNA vol. 11. FNA vol. 11.
Parent taxa Fabaceae > subfam. Faboideae > Desmodium Fabaceae > subfam. Faboideae > Desmodium
Sibling taxa
D. arizonicum, D. batocaulon, D. canadense, D. canescens, D. cinerascens, D. cuspidatum, D. floridanum, D. grahamii, D. gramineum, D. illinoense, D. incanum, D. intortum, D. laevigatum, D. lindheimeri, D. lineatum, D. marilandicum, D. metcalfei, D. nuttallii, D. ochroleucum, D. paniculatum, D. procumbens, D. psilocarpum, D. psilophyllum, D. rosei, D. rotundifolium, D. scopulorum, D. scorpiurus, D. sessilifolium, D. strictum, D. tenuifolium, D. tortuosum, D. triflorum, D. tweedyi, D. viridiflorum, D. ×humifusum
D. arizonicum, D. batocaulon, D. canadense, D. canescens, D. cinerascens, D. cuspidatum, D. floridanum, D. grahamii, D. gramineum, D. incanum, D. intortum, D. laevigatum, D. lindheimeri, D. lineatum, D. marilandicum, D. metcalfei, D. nuttallii, D. ochroleucum, D. paniculatum, D. procumbens, D. psilocarpum, D. psilophyllum, D. retinens, D. rosei, D. rotundifolium, D. scopulorum, D. scorpiurus, D. sessilifolium, D. strictum, D. tenuifolium, D. tortuosum, D. triflorum, D. tweedyi, D. viridiflorum, D. ×humifusum
Synonyms D. wislizeni, Meibomia retinens Meibomia illinoensis
Name authority Schlechtendal: Linnaea 12: 311. (1838) A. Gray: Proc. Amer. Acad. Arts 8: 289. (1870)
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