Desmodium arizonicum |
Desmodium retinens |
|
---|---|---|
Arizona tick trefoil |
Santa Rita Mountain ticktrefoil |
|
Habit | Herbs, perennial. | Herbs, perennial, diffuse; base woody, rootstock woody. |
Stems | erect or ascending, usually striate, sparsely branched, 20–80 cm, pubescent. |
erect, ascending, or procumbent, usually striate, 30–60(–100) cm, sparsely to densely pilose and uncinate-pubescent. |
Leaves | trifoliolate; stipules caducous, narrowly ovate, 6–8 mm; petiole 1–5 mm; leaflet blades narrowly oblong-elliptic to linear, apex acute, surfaces villosulous; terminal blade 40–60 × 4–10 mm, length 3.5–10 times width. |
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. |
Inflorescences | usually unbranched; rachis uncinate-puberulent; primary bracts caducous, broadly ovate, 4.5–5.5 mm. |
usually unbranched, sometimes branched; rachis patent uncinate-puberulent; primary bracts narrowly ovate, 2.5–3 mm. |
Pedicels | 8–15 mm. |
8–15 mm. |
Flowers | calyx 3 mm, uncinate-puberulent, lobes pubescent, tube 1.2 mm; abaxial lobes 2 mm, lateral lobes 1.5 mm; corolla blue-purple, 5–6 mm. |
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. |
Loments | sutures undulate abaxially, crenate adaxially; connections adaxial, 1/3 as broad as segments; segments (2 or)3–5, semiorbiculate, 4–5(–6) × 4 mm, rounded abaxially, convex adaxially, uncinate-puberulent; stipe 1–2 mm. |
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. |
2n | = 22. |
|
Desmodium arizonicum |
Desmodium retinens |
|
Phenology | Flowering summer–fall. | Flowering late summer–fall. |
Habitat | Oak-juniper or pine woodlands, canyons, roadsides. | Wooded or grassy rocky slopes, oak or oak-pine forests. |
Elevation | 1700–2500 m. (5600–8200 ft.) | 1400–2100 m. (4600–6900 ft.) |
Distribution |
AZ; NM; Mexico (Baja California, Chihuahua, Sinaloa, Sonora, Tamaulipas)
|
AZ; Mexico; Central America (Guatemala) |
Discussion | In the flora area, Desmodium arizonicum is known from southeastern Arizona and adjacent New Mexico. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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.) |
Source | FNA vol. 11. | FNA vol. 11. |
Parent taxa | Fabaceae > subfam. Faboideae > Desmodium | Fabaceae > subfam. Faboideae > Desmodium |
Sibling taxa | ||
Synonyms | Meibomia arizonica | D. wislizeni, Meibomia retinens |
Name authority | S. Watson: Proc. Amer. Acad. Arts 20: 363. (1885) | Schlechtendal: Linnaea 12: 311. (1838) |
Web links |