7. Funastrum utahense (Engelmann) Liede & Meve, Nordic J. Bot. 22: 589. 2003.
[E]
Utah milkvine
Astephanus utahensis Engelmann, Amer. Naturalist 9: 349. 1875; Cynanchum utahense (Engelmann) Woodson
Stems very sparsely pilosulose, more densely so at nodes. Leaves persistent, sessile, stipular colleter 1 on each side of leaf base; blade filiform, 1–4 × 0.05–0.2 cm, chartaceous, base cuneate, margins plane, apex acute or attenuate, mucronate, 1-veined, surfaces sparsely puberulent with curved trichomes, margins ciliate, laminar colleters absent. Inflorescences solitary at nodes, 3–6(–10)-flowered; peduncle 0.5–2 cm, sparsely puberulent with curved trichomes to glabrate; bracts caducous, 1, at base of each pedicel. Pedicels 3–10 mm, puberulent with curved trichomes. Flowers: calyx lobes linear-lanceolate, 1.3–2.5 mm, apex acute, spreading with reflexed tips, pilose, ciliate, colleters unknown; corolla yellow, becoming orange with age, green at base of tube, tubular, tube 1–3 mm, lobes incurved, closing corolla but for a pin hole, lanceolate, 0.5–1.5 mm, apex acute, puberulent to glabrate abaxially; corona absent; style apex shallowly convex. Follicles usually solitary, fusiform, 4–9 × 0.5–1 cm, apex acuminate, puberulent with curved trichomes to glabrate. Seeds not seen.
Flowering Mar–Jun(–Oct); fruiting May–Oct. Plains, arroyos, hills, bajadas, dunes, sand, silt, gravel, basalt, limestone, conglomerate, desert scrub, desert grasslands; 200–1200 m; Ariz., Calif., Nev., Utah.
Funastrum utahense is the most distinctive species in the genus and is placed here with some hesitation. Phylogenetically, it has been associated with species of Funastrum and Pattalias, but morphologically this species is not comfortably placed in either genus due to its unique, tubular corolla and lack of a corona. Whether it is best placed here, in Pattalias, or in a monospecific genus awaits further study. Like F. hirtellum, the range of F. utahense is restricted to the watershed of the lower Colorado River. However, F. utahense is far less commonly encountered. It is considered to be rare and of conservation concern in Arizona and Utah.
