Ipomoea obscura

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

413. Ipomoea obscura (L.) Ker-Gawl., Bot. Reg. 3: t. 239. 1817. (Ker-Gawler 1817: t. 239)

Convolvulus obscurus L., Sp. Pl., ed. 2, 2: 220. 1762. (Linnaeus 1762: 220). Type. Icon in Dillenius, Hort. Eltham. 1: 99, t. 83, f. 95 (1832), designated by Meeuse (1958: 746).

Ipomoea curassavica All. , Auct. Syn. 10. 1773. (Allioni 1773: 10). Type. Cultivated plant grown from seed collected in Curaçao (holotype TO).

Ipomoea luteola R. Br. , Prodr. 485. 1810. (Brown, R 1810: 485). Type. AUSTRALIA. Queensland, Keppell Bay, R.Brown 2744 (lectotype BM001040635, designated here).

Ipomoea insuavis Blume Cat. Gen. Buitenzorg 50. 1823. (Blume 1823: 50). Type. INDONESIA. Java, Buitenzorg (no type cited).

Ipomoea fragilis Choisy in A.P. de Candolle , Prodr. 9: 372. 1845. (Choisy 1845: 372). Type. SOUTH AFRICA. Cape, Maadji Mountain, W.J. Burchell 2362 (lectotype G, designated by Meeuse and Welman (2000: 99), not seen, isolectotypes GH, K).

Ipomoea obscura var. fragilis (Choisy) Meeuse, in Dyer , Fl. Pl. Afr. 31: pl. 1222. (Meeuse 1956: pl.1222).

Ipomoea acutiflora A. Rich. , Tent. Fl. Abyss. 2: 7. 1851. (Richard 1851: 7). Type. ETHIOPIA. Choa, Quartin Dillon & Petit s.n. (syntypes P).

Ipomoea longipes Engl. , Bot. Jahrb. Syst. 10 (3): 246. 1888. (Engler 1888: 246), nom. illeg., non Ipomoea longipes Garcke (1849) . Type. SOUTH AFRICA. Griqualand West, R. Marloth 981 (holotype B†, isotype K000097277).

Ipomoea inconspicua Baker, Bull. Misc. Inform. Kew 1894 (86): 71. (Baker 1894: 71). Type. MALAWI. Nakulambe, Buchanan 1881 (holotype K000097201).

Ipomoea saltiana Rendle, J. Bot. 32: 178. 1894. (Rendle 1894: 178). Type. ETHIOPIA, sine loc., Salt s.n. (holotype BM000930428).

Ipomoea demissa Hallier f., Jahrb. Syst. 18: 129 1893[pub. 1894]. (Hallier 1893b: 129). Type. TANZANIA, Tabora District, Boehm 83 (B†).

Ipomoea obscura var. demissa (Hallier f.) Verdc., Kew Bull. 33: 165. 1978. (Verdcourt 1978: 165).

Ipomoea fragilis var. pubescens Hallier f., Bull. Herb. Boiss.7: 51. 1899. (Hallier 1899a: 51). Type. Based on Ipomoea longipes Engl. and I. inconspicua Baker

Ipomoea obscura var. indica Hallier f., Bot. Jahrb. 28: 39. 1899. (Hallier 1899e: 39), nom. illeg., autonymic var.

Ipomoea obscura var. abyssinica Hallier f., Bot. Jahrb. 28: 39. 1899. (Hallier 1899e: 39). Type. ETHIOPIA. Gandia, Schimper 801 (holotype B†, isotypes BR, G, K, S, W).

Ipomoea obscura var. sagittifolia Verdc. , Kew Bull. 13: 210. 1958. (Verdcourt 1958: 210). Type. TANZANIA. Kahama District, Morgan 10 (holotype BM).

Type.

Based on Convolvulus obscurus L.

Description.

Twining or trailing perennial herb; stems rather slender, pilose or glabrescent, up to 1.2 m long. Leaves petiolate, 2.5-9 × 0.5-7.5 cm, ovate, shortly acuminate, base cordate with rounded auricles, rarely sagittate ( var. sagittifolia ), glabrous or shortly pubescent on both surfaces; petioles 1-8 cm, glabrous or pubescent. Inflorescence of few-flowered, shortly pedunculate axillary cymes; peduncles 3.5-4 cm, glabrous, pubescent or thinly pilose; bracteoles 1-1.5 mm, lanceolate; secondary peduncles 0.5-1.5 cm; pedicels 10-20 mm, often bent or recurved, glabrous or, less commonly, pubescent or pilose; sepals 4-8 × 2-4 mm, glabrous, often wrinkled or muricate, margins scarious, usually glabrous but occasionally pilose with long white trichomes, slightly unequal, outer ovate, acute to shortly acuminate or mucronate, inner ovate-elliptic obtuse, occasionally mucronate; corolla 1.5-2.5 cm long, white, yellow or orange with purple base to the inside of the tube, narrowly funnel-shaped, glabrous, limb often weakly lobed, 3-4 cm diam. Capsules 18 × 12 mm, globose, glabrous; seeds 4-5 × 2.5-3.5 mm, minutely tomentellous.

Illustration.

Bosser and Heine (2000: 55); Deroin (2001: 223).

Distribution.

Generally thought to be an African species introduced into the Caribbean region.

JAMAICA. W. Stearn 164 (S).

DOMINICAN REPUBLIC. H.A. Allard 13214 (S).

LESSER ANTILLES. Antigua: H.E. Box 1308 (BM, K). Barbados: A.McIntosh 351 (K). Guadeloupe: Raynal-Roques & Jérémie 21118 (K, P); Marie Galante fide Powell (1979). Dominica: C. Whitefoord 5505 (BM).

HAWAII. Kauai, U.J. Faurie 1042 (BM); Judd et al. s.n. [25/9/1937] (K).

Notes.

This hardly differs from Ipomoea ochracea except in the smaller dimensions of its corolla. It is, however, much more widespread in the Old World Tropics than Ipomoea ochracea .

Ipomoea obscura var. fragilis differs from the type in the concolorous pale yellow colour of the corolla. It is southern African in distribution.