Ipomoea sescossiana Baillon

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

279. Ipomoea sescossiana Baillon , Bull. Mens. Soc. Linn. Paris 1: 385. 1883. (Baillon 1883: 385)

Ipomoea pringlei A. Gray , Proc. Amer. Acad. Arts 22: 307. 1887. (Gray 1887: 307). Type. MEXICO. Chihuahua, C.G. Pringle 782 (holotype GH00054532, isotypes AC, BM, COLO, F, IBUG, K, MA, MEXU, MIN, MO, MSC, NDG, NY, P, RSA, S, TEX).

Type.

MEXICO. San Luis de Potosí, Sescosse s.n. (lectotype P03560164, designated here; isolectotypes P, US).

Description.

Bushy perennial herb to c. 1 m, plant entirely glabrous. Leaves shortly petiolate, short, 1.5-3.5 cm long, ± pinnately divided into linear segments 0.5-1.5 × 0.1 cm; petioles 0.2-0.7 cm. Inflorescence of solitary, long-pedunculate flowers; peduncles stout, 1-5 cm; bracteoles 1-2 mm, lanceolate, caducous; pedicels 0.6-1.6 cm, widened upwards; sepals unequal, outer 5-7 × 3-4 mm, broadly or narrowly ovate-elliptic, obtuse, scarious-margined, inner 9-10 × 7 mm, obovate or broadly elliptic, rounded with broad, scarious margins and green centre; corolla 7.5-9 cm long, deep bluish-pink with a pale tube, glabrous, funnel-shaped, limb unlobed, 4-7 cm diam. Capsules 10-18 × 8-10 mm, ovoid, rostrate, mucro c. 3 mm long, glabrous; seeds 7 × 4 mm (possibly immature), pubescent.

Illustration.

Figure 140 .

Distribution.

Endemic to northern Mexico growing from 1600 to 2350 m on dry rocky mountains.

MEXICO. Aguas Calientes: Tepezalá, De La Cerda-García 1416 (IEB). Chihuahua: Mun. Guerrero, R. Spellenberg 13842 (ARIZ, NMC); 41 km S. of Villa Ahumada, J. Henrickson 5867 (MEXU); Los Encinillos, H.S. Gentry 8218 (MEXU). Coahuila: 8.4 miles S of Moctezuma, R. Worthington 7284 (ARIZ, TEX, UTEP). km 15 W of Concepción del Oro, L.R. Stanford et al. 534 (ARIZ, NY). Durango: El Oro to Guanacivi, E.W. Nelson 4729 (K); L. McGill 9305 (ASU). San Luis de Potosí: C.L. Lundell 5149 (TEX); Venado, F. Sánchez 412 (ASU, DES, MEXU). Sonora: fide Felger et al. (2012). Zacatecas: Junction of Rutas 54 and 45, W.L. Wagner & J.C. Solomon 4212 (MO); NW of Fresnillo, G.L. Webster & G.J. Breckon 15505 (MEXU).

• Molecular sequence data suggests species 280-288 (and possibly 289) form a natural group but no obvious morphological feature seems to unite the whole clade although individual species clusters are readily discernible.

Figures

Figure 140. Ipomoea sescossiana. A habit B outer sepal C inner sepal. Drawn by Rosemary Wise from Pringle 782.