Ipomoea leptophylla Torr. in J.C. Fremont

Wood, John R. I., Munoz-Rodriguez, Pablo, Williams, Bethany R. M. & Scotland, Robert W., 2020, A foundation monograph of Ipomoea (Convolvulaceae) in the New World, PhytoKeys 143, pp. 1-823 : 1

348. Ipomoea leptophylla Torr. in J.C. Fremont , Rep. Exped. Rocky Mts. 94. 1845. (Torrey 1845: 94)

Convolvulus caddoensis Buckley , Proc. Acad. Nat. Sc. Philadelphia 165: 6. 1862 [pub. 1863]. (Buckley1863: 6). Type. UNITED STATES. [Texas], Addo peak in NW Texas, Durand s.n. sine data (probable holotype PH00006612).

Type.

J.C. Frémont s.n. (holotype NY00319064, isotypes K, NY).

Description.

Erect branched undershrub, stems glabrous, yellowish, rootstock massive, spindle-shaped, woody. Leaves subsessile, 3.5-10 × 0.2-0.6 cm, narrowly oblong, obtuse and mucronate, base cuneate, glabrous; petioles 2-6 mm. Inflorescence of few-flowered axillary cymes; peduncles 0.5-3.5 cm, rather stout; bracteoles 1-3 mm, deltoid, caducous; pedicels 7-15 mm, thickened upwards and of different texture to peduncle; sepals unequal, outer 5-8 mm, ovate, obtuse with scarious margins, inner similar but 10-12 mm, broadly elliptic and more rounded; corolla 5.5-7 cm long, funnel-shaped, glabrous, pink, limb entire, 4.5-7 cm diam. Capsules 14 × 14 mm, subglobose, rostrate with 6 mm long mucro, glabrous, much larger than calyx; seeds 10 × 4 mm, brown, tomentellous.

Illustration.

Figure 166 ; Haddock et al. (2015: 235).

Distribution.

Prairie region of Midwest United States extending into northern Mexico. It is usually found in short grassland on sandy or gravelly soil mostly between 1000 and 1900 m.

MEXICO. Chihuahua: 10 km W of Chihuahua, L. McGill 8280 (ASU).

UNITED STATES. Colorado: Denver, J.L. Wingate 8527 (KHD); Adams Co., D. Demaree 29534 (BM); North Denver, Eastwood 39 (K). Kansas: B. Kuhn 7375 (RM). Nebraska: Sheridan, S.M. Clarke 15-17 (BRY). New Mexico: Kiowa Nat. Grassland, Van Devender 84 -377 (ARIZ); Fendler 660 (BM). Oklahoma: Glass Mts., M. Fishbein 6913 (ARIZ). South Dakota: hot springs at Mammoth site, M. Nee 21515 (NY, FTG); Black Hills, P.A. Rydberg 903 (K). Texas: Lindheimer fasc. 4: 661 (BM, OXF, P); Gaines Co, H.S. Gentry 20616 (ARIZ). Wyoming: Goshen, Fort Laramie, B.C. Buffum s.n, 5/9/1892 (RM); E.W. Nelson 2575 (BM, US).

Note.

Differs from Ipomoea longifolia in the linear-oblong leaves and shorter sepals. The rootstock is reported to be “massive” with the "diam. of a telephone pole" (Weber and Wittmann 2012: 166).

Figures

Figure 166. Ipomoea leptophylla. A habit B outer sepal C inner sepal D corolla opened out to show stamens E ovary and style F fruiting calyx and capsule. Drawn by Rosemary Wise A-C E from Fendler 660; D from Eastwood s. n.; F from Lindheimer fasc. 4: 66.