Ipomoea praecana House

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

79. Ipomoea praecana House , Ann. New York, Acad. Sci. 18: 227. 1908. (House 1908b: 227)

Type.

MEXICO. Oaxaca, near Reyes, E.W. Nelson 1823 (holotype US00111447, isotypes GH, NY).

Description.

Vigorous twining or sprawling liana to 4 m; stems and all vegetative parts densely white-tomentose. Leaves petiolate, 8-20 × 6-20 cm, ovate to suborbicular, obtuse or acute, base subtruncate to shallowly cordate with rounded auricles, densely white-tomentose on both surfaces but abaxially paler; petioles 4-35 mm. Inflorescence of shortly pedunculate 3-6-flowered cymes borne on side branches so appearing to form elongate bracteate racemes; bracts resembling small leaves; peduncles very short, 0.5-3 cm, tomentose; bracteoles 10-20 × 4-6 mm, oblong-elliptic, caducous; pedicels 2-3.5 cm, sulcate, thickened upwards, tomentose; sepals 15-20 × 7-10 mm at anthesis but strongly accrescent in fruit to 25 × 15 mm, ovate to elliptic, obtuse, densely tomentose; corolla 6-10 cm long, white, subhypocrateriform, tomentose, more densely so on midpetaline bands, limb c. 5 cm diam., undulate. Capsules 20-25 × 15-18 mm, ovoid, glabrous; seeds 11-14 × 5-6 mm, black with long marginal hairs 12-20 mm long.

Illustration.

Figure 50 .

Distribution.

Dry deciduous forest and scrub, often on rocky soils below 1100 m from central Mexico south to Nicaragua.

NICARAGUA. Estelí, Cerro El Almendro, Condega, P. Moreno 25334 (BM); Matagalpa, Loma Chichigua, W.D. Stevens et al. 5672 (BM, MO); A. Molina 23332 (F).

HONDURAS. Francisco Morazán, V. Mendoza 112 (BM); J.V. Rodríguez 3272 (F).

EL SALVADOR. Área protegída San Juan Buenavista, R.A. Carballo 17 (MO, W).

GUATEMALA. W. Kellerman 5645 (US); J.J. Castillo Mont et al. 1694 (MO).

MEXICO. Chiapas: Tuxtla Gutiérrez-San Cristóbal, P.J. Stafford et al. 235 (BM). Colima: R. McVaugh 26236 (MICH). Est. México & Dist. Fed.: Temascaltepec, Guayabal, G.B. Hinton 3360 (BM, K, MEXU); ibid., Calera, G.B. Hinton 5887 (K); ibid., Salitre, G.B. Hinton 8739 (K, MO). Guerrero: Petalán, J. Soto Nuñez 12121 (MEXU); Tierra Colorada, Kruse 992 (MEXU). Michoacán: J.V. Dieterle 3176 (MICH); Aquila, E. Carranza & I. Silva 6659 (IEB, MEXU). Morelos: Cuernavaca, C.G. Pringle 7229 (GH). Oaxaca: Cuicatlán, R. & M.L. Torres 6908 (MEXU, MO); San Juan Bautista, Cuicatlán, J.P. Abascal 118 (MEXU). Querétaro: Cerro La Pedrera, L.M. Chávez 6 (IEB, MEXU).

Note.

This species was placed in the Arborescens group by McPherson (1981) but both nuclear data and ITS indicate its more correctly placed in the Jalapa radiation, to which it conforms morphologically.

Figures

Figure 50. Ipomoea praecana A habit B abaxial leaf surface C outer sepal D inner sepal E corolla opened out to show stamens F ovary and style G calyx and capsule H seed. Drawn by Rosemary Wise A-F from Mendoza 112; G, H from Stafford et al. 235.