A foundation monograph of Ipomoea (Convolvulaceae) in the New World Author Wood, John R. I. Author Munoz-Rodriguez, Pablo Author Williams, Bethany R. M. Author Scotland, Robert W. text PhytoKeys 2020 143 1 823 http://dx.doi.org/10.3897/phytokeys.143.32821 journal article http://dx.doi.org/10.3897/phytokeys.143.32821 1314-2003-143-1 F6F11A6EE4FF5A1885CEA2B60AE965A5 111. Ipomoea pochutlensis J.R.I. Wood & Scotland, sp. nov urn:lsid:ipni.org:names: Type. MEXICO. Oaxaca, Pochutla, Mu. San Miguel del Puerto, copalitilla, cascadas del rio , 30 July 1999, J. Rivera H., S. Salas M. & E. Martinez S. 1741 (holotype MEXU1234493). Diagnosis. Bears a superficial resemblance to Ipomoea riparum in its very shortly pedunculate bracteolate cymes but distinguished by the very unequal, whitish-green, glabrous sepals and the glabrous white corolla. Description. Robust twining perennial of unknown height; stems glabrous, somewhat sharply angled. Leaves petiolate, 8-12 x 7-10, shallowly 3-lobed, base cordate, apex acute, both surfaces glabrous, minutely white-punctate, abaxially paler, minutely white-punctate and with prominent white veins; petioles 5-8 cm, pseudo stipules arising at their base. Inflorescence of compact, shortly pedunculate, axillary cymes with up to 10 flowers; peduncles 5-6 mm; lower bracteoles c. 10 x 3 mm, broadly lanceolate with petiolar base, acuminate, persistent; secondary peduncles 1-2 mm, upper bracteoles c. 5-6 x 1 mm, linear, acute, persistent; sepals very unequal, very pale whitish-green with darker veins, outer 5-6 x 2-2.5 mm, ovate, apiculate, inner 10-11 x 5 mm, broadly oblong-oblanceolate, rounded or retuse; corolla 4-4.5 cm long, funnel-shaped, white, glabrous, limb c. 2-3 cm wide. Capsules and seeds not seen. Illustration. Figure 74 . Figure 74. Ipomoea pochutlensis . A habit B sepals (right outermost, left-second, middle inner) C inflorescence showing bracteoles and branching D corolla opened out. Drawn by Rosemary Wise from Rivera H., Salas M. & Martinez S. 1741 Distribution. Endemic to Oaxaca in Mexico, where it was found by a stream in semi-evergreen forest at 320 m. Only known from the type collection. MEXICO. Oaxaca : Pochutla, Mun. San Miguel del Puerto, J. Rivera et al. 1741 (MEXU). Note. The exact relationships of this species are unclear. Molecular sequencing using ITS suggests it is related to Ipomoea brasiliana but there is little obvious morphological similarity. In its very shortly pedunculate bracteolate cymes it bears some resemblance to I. riparum but the very unequal, whitish-green glabrous sepals and the white glabrous corolla are very distinct.