Ipomoea melancholica

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

407. Ipomoea melancholica J.R.I. Wood & Buril, Kew Bull. 72 (44): 9. 2017. (Wood et al. 2017b)

Type.

BRAZIL. Alagoas, Quebrangulo, REBIO Pedra Talhada, 6 Sept. 2012, B.S. Amorin, J.L. Costa-Lima, W.M. Pora, V.S. Sampaio, M.A. Chagas 1658 (holotype JPB, isotype UFP).

Description.

Slender twining herb of unknown height; stems pilose. Leaves petiolate, 4.5-10 × 3.5-8.5 cm, ovate and entire, undulate to shallowly 3-lobed, base cordate with rounded auricles, apex shortly acuminate, obtuse and mucronulate, adaxially thinly pubescent, abaxially paler, glabrous; margins ciliolate; petioles 1-8.5 cm pilose. Inflorescence of solitary, pedunculate flowers from the leaf axils; peduncles 3-11 mm; bracteoles 1-2 mm, lanceolate; pedicels 9-13 mm, thickened upwards, slightly winged, often recurved, thinly pubescent; sepals subequal, 7-8 × 1.75 mm, lanceolate, acuminate, pubescent and ciliate; corolla 2.5-3 cm long, pink, narrowly funnel-shaped, apparently glabrous, midpetaline bands ending in small teeth, limb c. 1.5 cm diam.; style globose. Capsules 10 × 7 mm, ovoid, shortly rostrate, glabrous; seeds 4, 5 × 2.5 mm, grey, densely tomentose.

Illustration.

Wood et al. (2017b: 7).

Distribution.

Endemic to Mata Atlântica in NE Brazil.

BRAZIL. Alagoas: G.A. Gomes-Costa 166 (JPB, UFP). Ceará: Inaçio de Azevedo. J. Eugenio 1007 (GH), Serra das Almes, F.S. Araujo 1424 (HUEFS).

Note.

This species has been interpreted as a form of Ipomoea acanthocarpa (Choisy) Aschers & Schweinf. but differs in the solitary flowers and very shortly rostrate capsule. It has also been identified as I. minutiflora (M. Martens & Galeotti) House but differs in its larger solitary pink flowers and larger capsules. It might also be thought to be a depauperate species from the Pharbitis Clade such as I. indica (Burm.) Merrill but the 4-seeded capsules and small sepals rule that out. The species seems closest to I. chiquitensis . Both species have leaves adaxially pubescent but abaxially glabrous and both have similar-sized, acuminate sepals with white margins as well as deflexed fruiting peduncles. However, I. chiquitensis always has entire leaves, the stem is glabrous but the leaves and sepals are much more hirsute, and the capsule is much more prominently rostrate. The position of I. melancholica here cannot be confirmed as it is only inferred from its morphology.