Ipomoea steerei (Standl.) L.O. Williams

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

179. Ipomoea steerei (Standl.) L.O. Williams , Fieldiana, Bot. 32 (12): 195. 1970. (Williams 1970a: 195)

Exogonium steerei Standl. , Publ. Carnegie Inst. Wash. 461 (4): 83. 1935. (Standley 1935: 83). Type. MEXICO. Yucatán, Chichen Itza, W.C. Steere 1545 (holotype F668631, isotypes G, LL, MICH, MO, NY).

Ipomoea clewellii C. Nelson , Phytologia 72 (6): 401. 1992. (Nelson 1992: 401). Type. HONDURAS. Gracias a Dios, Ahuas, A. Clewell 3679 (TEFH).

Type.

Based on Exogonium steerei Standl.

Description.

Perennial twining plant with wiry, pubescent stems up to 4 m high. Leaves shortly petiolate, 2.5-6 × 2-3.5 cm, oblong-oblanceolate or oblong-elliptic, cuneate, apex acute and strongly mucronate, adaxially thinly pilose, green, abaxially densely adpressed silvery-pilose; petioles 3-11 mm, pubescent. Inflorescence of solitary or few-flowered axillary cymes; peduncles 1 -3 cm, densely silvery-pilose; bracteoles 10-18 × 2-3.5 mm, oblanceolate, acute, tapering to a petiole-like base, caducous; pedicels 8-15 mm, glabrous to thinly pubescent, especially below; sepals unequal, coriaceous, glabrous with scarious margins, outer 5-7 × 3-4 mm, elliptic to suborbicular, rounded to obtuse, inner 9-10 × 5-6 mm, elliptic to obovate, rounded to retuse; corolla 4.5-5.5 cm long, pink, glabrous, funnel-shaped, limb 3.5 cm diam., unlobed. Capsules 12-15 × 6-7 mm, ovoid, acute, glabrous; seeds 8-10 mm, ovoid, pilose.

Distribution.

Deciduous woodland, flooded forest and mangroves at low altitudes in Central America; rather uncommon.

HONDURAS. Type of Ipomoea clewellii .

GUATEMALA. Petén, P.N. Tikal, Bajo de Santa Fe, C.L. Lundell 16492 (MO).

MEXICO. Campeche: Hecelchakán, E. & H. Cabrera 13968 (F, MO), 13943 (BM, IEB, MEXU); Calakmul, E. Martínez et al. 35970 (IEB). Quintana Roo: camino a Vigía Chica, E. Cabrera & H. Cabrera 3529 (BM, MEXU, MO, K); ibid., O. Téllez & E. Cabrera 3186 (BM, MEXU, MO). Yucatán: Valladolid, Xuilub, B. Morgensen 1064 (AAU, K).

Note.

The oblong-elliptic leaves with long, silvery appressed hairs abaxially are distinct as is the habitat.

• Species 180-182 form a group of three Mexican species with a hypocrateriform corolla and a tendency to be leafless at anthesis.