Ipomoea horsfalliae Hook.

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

211. Ipomoea horsfalliae Hook. , Bot. Mag. 61, t. 3315. 1834. (Hooker 1834b: t. 3315)

Type.

Plate 3315 In Bot. Mag., epitype. K000612699, designated by Wood and Scotland 2017c: 11.

Description.

Liana climbing to 10 m over scrub; stems woody, glabrous, often muricate with blunt warts. Leaves palmately divided into 5-7 leaflets, leaflets 4-14 × 0.8-3 cm, sessile or basally fused, oblong-elliptic, obovate or oblanceolate, acuminate or obtuse, narrowly cuneate at base, glabrous, abaxially paler; petioles 3-7 cm. Inflorescence of axillary pedunculate cymes, which are often aggregated to form a many-flowered terminal panicle; peduncles and panicle rhachis 2.5-15 cm long; secondary peduncles, if present, 1.5-5 cm; bracteoles 3-4 mm, lanceolate with scarious margins, caducous; pedicels 10-15 mm; sepals coriaceous, slightly unequal, outer 7-8 × 5 mm, ovate, convex, obtuse with narrow scarious margin, inner 9-10 × 7 mm, elliptic, rounded with broad scarious margin; corolla 4.5-6 cm long, glabrous, usually dark red with paler tube, narrowly funnel-shaped, limb distinctly lobed, 3-4 cm diam., stamens held at mouth or slightly exserted. Capsules rostrate, glabrous; seeds with long brown marginal hairs.

Illustration.

Figures 84B , 107A ; Acevedo-Rodríguez (2005: 170); Wood and Scotland (2017c: 12-13).

Distribution.

Cultivated throughout the tropics. The following records are all of cultivated plants.

BRAZIL. Minas Gerais: Y. Mexia 5744a (NY). Rio de Janeiro: C.G. Pinto 222 (RB); J.R. Mattos 380 (RB). São Paulo: G.D. Passerini s.n. [20/4/2003] (RB).

SURINAM. Fide Austin and Huáman (1996).

GUYANA. Fide Austin and Huáman (1996).

VENEZUELA. Fide Austin and Huáman (1996).

BERMUDA. S. Brown et al. 1952 (NY)

CUBA. Cienfuegos, J.G. Jack 4278 (A); La Habana, Bro. León 8499 (NY).

PUERTO RICO. Sintenis 4655 (BM, S); N.L & E.O. Britton 7419 (NY), 9178 (NY)

LESSER ANTILLES. U.S. Virgin Islands: St Croix: J.B. Thompson 1055 (NY). Guadeloupe: A. Duss 3086 (NY). Martinique: A. Duss 1882 (NY). Barbados: L.M. Andrews 646 (NY).

TRINIDAD. Fide Baksh-Comeau et al. (2016).

HAWAII. Fide http://www.starrenvironmental.com

Note.

Our understanding of Ipomoea horsfalliae has been set out elsewhere (Wood and Scotland 2017c) and is essentially that this is a cultivated plant distinct from all known wild populations but probably derived from Ipomoea lineolata , a Jamaican endemic. As understood here, I. horsfalliae is a variable ornamental species whose leaves can be divided into (3-) 5 (-7) sessile leaflets or are, less commonly, 3-5-lobed. The inflorescence is of compound cymes, the anthers shortly exserted or held at the corolla mouth. Most plants are sterile and capsules are rarely found. Reported by Powell (1979) and Acevedo-Rodríquez (2005) to hybridise with Ipomoea repanda producing 5-lobed leaves with flowers resembling those of I. repanda . These supposed hybrids and similar forms with 5-lobed leaves are here treated as I. horsfalliae but require investigation to confirm their status.

Figures

Figure 84. Photographs of Ipomoea species. A I. batatoides B I. horsfalliae C I. mauritiana D I. exserta E, F I. platensis. A Guillaume Leotard B Royal Botanic Gardens, Kew C S. SANT / Parc Amazonien de Guyane D John Wood E, F Mario Giorgetti.

Figure 107. Ipomoea horsfalliae A habit showing lobed leaves found in some cultivated forms. B-E I. lineolata B habit C outer sepal D inner sepal E corolla opened out to show stamens. Drawn by Rosemary Wise A from Jack 4278; B-E from Fosberg 42712.