Ipomoea setosa Ker-Gawl.

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

216. Ipomoea setosa Ker-Gawl. , Bot. Reg. 4: t. 335. 1818. (Ker Gawler 1818e: t. 335)

Type.

Icon, Ker Gawler, Bot. Reg. 4: t. 335, lectotype, designated by J.A. McDonald (1994: 110).

Description.

Scrambling perennial herb, stems with soft fleshy trichomes and bluish-green bloom but otherwise glabrous. Leaves petiolate, 10-32 × 10-32 cm, mostly 3-7(-9)-lobed to about halfway but sometimes ovate-orbicular, apex shortly acuminate, obtuse and mucronate, base cordate with rounded auricles, margin irregularly dentate with scattered teeth, both surfaces glabrous; petioles 5-14 cm, armed with soft fleshy trichomes. Inflorescence of long-pedunculate axillary cymes; peduncles 5-15 cm, usually armed with soft fleshy trichomes; bracteoles 5-10 × 2 mm, oblong, mucronate, caducous; secondary peduncles 1.5-3 cm; pedicels 1-4 cm, markedly thickened upwards, glabrous or armed with soft fleshy spines, often purplish-brown; sepals subequal, 8-10 mm at anthesis (accrescent to 16 mm in fruit), ovate, acute, convex, glabrous or with soft fleshy trichomes, purplish-brown, the margins scarious; corolla 4-10 cm long, funnel-shaped, pink, glabrous, limb c. 2.5 cm diam. Capsules subglobose, 15 mm long, glabrous; seeds 7 × 5 mm, woolly, nearly black.

Distribution.

Widely distributed but scattered and never common throughout tropical America north to Mexico but apparently absent from Colombia and the Guianas and rare in Brazil.

Variation.

Ipomoea setosa is an isolated species, and as here delimited very variable. All specimens of Ipomoea setosa we have seen from South America except Eggers 15768 from Ecuador differ from the type in having sepals that lack fleshy trichomes. They always have 3-lobed leaves and the corolla is relatively small, being 5-6.5 cm long. Specimens from Mexico have 5-9-lobed leaves, a large corolla up to 10 cm in length and sepals densely covered in soft spines. Eggers 15768 from Ecuador and most plants from Central America are intermediate between these extremes and accord with the type, having 3-lobed leaves and sepals armed with fleshy trichomes. Plants mostly from Belize generally treated as I. sepacuitensis seem to be part of the same species differing only in the large corolla (similar to Mexican examples) and the absence of trichomes except on the stem. These four taxa are here treated as geographical subspecies which can be separated by the following key: