Ipomoea zacatecana

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

239. Ipomoea zacatecana J.R.I. Wood & Scotland, sp. nov

urn:lsid:ipni.org:names:

Type.

MEXICO. Zacatecas, Mun. Villanueva, Carr. 54 on Zacatecas-Guadalajara highway, c. 1 km S del desvio a Laguna del Carretero, 23 Aug. 1995, E. D. Enriquez E. 568 (MEXU964013).

Diagnosis. Superficially resembles Ipomoea purpurea but differs in the prominent lateral tooth and sagittate base of the leaves, the finely acuminate sepals and mostly solitary flowers with a pubescent corolla.

Description.

Perennial herb from woody, xylopodium-like rootstock, much-branched at the base; stems prostrate, up to 1 m long, thinly pilose, reddish when young but woody, glabrous and muricate when old. Leaves petiolate, 1.5-3.5 × 0.7-2.4 cm, rather small, ovate, acute, base sagittate with acute auricles, the margin sometimes with a large tooth towards the base, both surfaces green, thinly pilose; petioles 0.4-1.9 cm, pubescent. Inflorescence of 1-3-flowered pedunculate, axillary cymes, the flowers mostly solitary; peduncles 1-4.5 cm, thinly pilose; bracteoles 5-7 mm, linear, relatively persistent; pedicels 3-6 mm, thinly pilose; sepals subequal, 12-13 × 5-6 mm, ovate, finely acuminate, the base rounded to cuneate, bristly white-pilose; corolla 4.5-5.5 cm long, funnel-shaped, deep pink with whitish tube, pubescent towards the apex. Capsules and seeds unknown.

Illustration.

Figure 123 .

Distribution.

Endemic to Zacatecas in Mexico, growing in dry grassland in open oak woodland with Bouteloua , Chloris and Muhlenbegia.

MEXICO. Zacatecas: type collection.

Note.

The placement of this species is uncertain but it is provisionally placed here because it bears a superficial resemblance to Ipomoea purpurea , although it differs in the prominent lateral tooth and sagittate base of the leaves, the finely acuminate sepals and mostly solitary flowers with a pubescent corolla. It is also possible that its correct placement is near I. rupicola as it has similar small leaves often with a lateral tooth and a pubescent corolla. However, the sepals are quite different.

Figures

Figure 123. Ipomoea zacatecana. A habit B abaxial leaf surface C outer sepal D inner sepal. Drawn by Rosemary Wise from Enriquez 568.