Ipomoea alterniflora Griseb.

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

183. Ipomoea alterniflora Griseb. , Cat. Pl. Cub. 202. 1866. (Grisebach 1866: 202)

Ipomoea obtusata Griseb. , Cat. Pl. Cub. 202. 1866. (Grisebach 1866: 202). Type. CUBA. C. Wright 3092 (holotype GOET000343, isotypes GH, K, YU).

Ipomoea obtusata var. latifolia Griseb. , Cat. Pl. Cub. 202. 1866. (Grisebach 1866: 202). Type. CUBA. C. Wright 3099 (holotype GOET?, not seen, isotypes G, GH, K, NY).

Ipomoea excisa Urb. , Symb. Antill. 9: 246. 1924. (Urban 1924b: 246). Type. CUBA. Prov. Pinar del Río [La Habana?], Sierra de Anafe, Loma San Gabriel, 21 March 1920, E.L. Ekman 10558 (holotype S07-4426).

Ipomoea cubensis sensu Urban (1925) et auct. mult.

Type.

CUBA occ., C. Wright s.n. (holotype GOET000347, possible isotypes GH, HAC ex Herb. Sauvalle 1635, NY).

Description.

Perennial twining herb, stem glabrous, pale brown. Leaves shortly petiolate, 2-7 × 1.5-3.5 cm, ovate to ovate-elliptic, sometimes shallowly lobed, apex shortly acuminate, acute, obtuse or, sometimes, retuse, base cordate to broadly cuneate, margin undulate, glabrous, abaxially paler; petioles 1-3 cm. Inflorescence of 1-5-flowered, axillary cymes; peduncles 1.5-6 cm; bracteoles caducous; secondary peduncles 0.3-1.7 cm; pedicels 6-20 mm; sepals slightly unequal, glabrous with scarious margins, coriaceous, outer 10 × 5-6 mm, ovate to suborbicular, rounded, inner 9-11 × 6-8 mm; corolla 4-5.5 cm long, funnel-shaped, greenish-yellow, greenish-yellow with pink throat or pink, glabrous. Capsules 10-14 × 7-10 mm, ovoid, rostrate, glabrous; seeds 5-7 × 3-4 mm, blackish with very long white, marginal hairs 6-10 mm long.

Distribution.

Ipomoea alterniflora is endemic to western Cuba from where all collections come. It appears to be a plant of forest relics.

CUBA. Isla de Juventud (Pinos): E.L. Ekman 12563 (S); A. Alvarez et al. (HAJB 455570). Pinar del Río: Mantua, Camarones, cima de Los Cabreros. A. Alvarez al. (HAJB 51183); Baños San Vicente, N.L. Britten et al. 7481 (NY); El Sapapo, Pinar de Sabanalamar, A. Areces et al. 28396 (HAC); Cabo Corrientes, Jaimanilas, R.A. Quintana et al. (HAJB 34218)-a good match with Wright 3092; Guanahacabibes, J. Bisse et al. (HAC, HAJB33208); Pinares de Cajálbana, La Palma, Bro. Alain & J. Acuña 1167, 1168 (HAC); Pinar del Rangel; Mogote de la Bandera, Roig 8358 (HAC). La Habana: Loma de la La Pita, San Miguel de Casanova, Bro. León 8388 (HAC); Sierra de Anafe, P. Wilson 11417 (NY); ibid., E. Ekman 13494 (BM, S); Caimito, J. Bisse et al. (HAJB 51278)-good match with Ekman 10558; Tetas de Managua, H.A. Van Hermann 318 (HAC). Matanzas: San Miguel de los Baños, J. Bisse & Rojas (HAJB 4522)-red-flowered. Villa Clara: Sierra Alta de Agabama, R. Berazaín et al. (HAJB 58044).

Notes.

Ipomoea alterniflora is a variable species characterised by its glabrous stem and leaves. The leaves are usually ovate, cordate and shortly acuminate to an obtuse apex but are sometimes lobed as in the possible isotypes in HAC and NY. The corolla colour in the holotype is whitish-green and this is clearly the same in the GH and HAC isotypes but the NY isotype is more darkly coloured and could be red.

The most variable aspects of this species lie in the leaf shape. In the type of Ipomoea obtusata the leaves are ovate-elliptic with a rounded to cuneate base and obtuse apex. In the type of I. excisa the leaves are ovate but the apex is retuse. Although the extreme forms are rather distinct, there are many specimens that connect these with more common forms typified by Wright 3099 and the type of I. alterniflora .