Ipomoea calcicola

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

241. Ipomoea calcicola J.R.I. Wood & Scotland, sp. nov

urn:lsid:ipni.org:names:

Type.

MEXICO. Querétaro, Cadereyta, Cerros calizos E. de Vizarrón, 13 Sept. 1994. J. Orozco H., R. Hernandez M. & C. Orozco L. 10806 (MEXU).

Diagnosis. Very distinct because of the 3-lobed, discolorous leaves, very long peduncles, acuminate, aristate sepals with prominent scarious margins and the reddish-purple pubescent corolla. Superficially it resembles Ipomoea spruceana but the shortly pubescent indumentum is very different from the pilose inflorescence of that species.

Description.

Twining perennial herb; stems dark reddish-brown, pubescent. Leaves petiolate, 2.5-4 × 3-5 cm, 3-lobed (sometimes 5-lobed, fide field notes), central lobe oblanceolate, laterals with rounded auricles and forward-pointing tips, base broadly cordate, apex finely acute, shortly mucronate, margin undulate to obscurely dentate, adaxially dark green, glabrous, abaxially pale green, pubescent; petioles 2.5-5 cm, pubescent. Inflorescence of compact, long-pedunculate, axillary cymes; peduncles 8-30 cm, pubescent; bracteoles 2-3 mm long, filiform; secondary peduncles very short, <1 cm; pedicels 5-13 mm, pubescent; sepals unequal, oblong-lanceolate, acuminate, shortly aristate, outer 10-11 × 2 mm, pubescent, dark green with white margins, inner 13-14 × 3 mm, glabrous, entirely scarious apart from a broad central green midrib; corolla c. 3-4 cm long, probably funnel-shaped, reddish-purple, pubescent. Capsules and seeds unknown.

Illustration.

Figure 125 .

Distribution.

Endemic to Querétaro in Mexico, where it grows in dry pine and oak woodland at 2200 m on rocky limestone soil.

MEXICO. Querétaro: type collection.

Note.

The distinct 3-lobed, discolorous leaves, very long peduncles, acuminate, aristate sepals with prominent scarious margins and the reddish-purple pubescent corolla mark out this species. There is a strong, probably superficial, resemblance to Ipomoea spruceana in the leaf shape and colouring, inflorescence structure and sepal shape but the shortly pubescent indumentum is very different from the pilose inflorescence of I. spruceana . The placement of I. calcicola is uncertain and its inclusion here is based on its similarity with I. spruceana .

Figures

Figure 125. Ipomoea calcicola. A habit B abaxial leaf surface C outer sepal D inner sepal. Drawn by Rosemary Wise from Orozco 10806.