Ipomoea opulifolia Rusby

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

63. Ipomoea opulifolia Rusby , Bull. Torrey Bot. Club 26: 150. 1899. (Rusby 1899: 150)

Type.

BOLIVIA. M. Bang 2506 (lectotype NY00319206, designated here; isolectotype US).

Description.

Vigorous twining species 3-4 m high, stems relatively stout, adpressed pilose; rootstock large tuberous. Leaves petiolate, 5-14 × 4-16 cm, 3-lobed to about half way, apex shortly acuminate and mucronate, base broadly cuneate to subtruncate to weakly cordate with rounded auricles, central lobe slightly narrowed to base, adaxially punctate with hair bases and scattered hairs, abaxially softly adpressed silvery-grey pilose, usually gland-dotted; petioles 2-11 cm, pubescent. Inflorescence of lax pedunculate, axillary cymes; peduncles 2-10 cm, densely pubescent; bracteoles 2 mm, scale-like, silvery-pilose, caducous; secondary peduncles 1.5 cm; pedicels 7-8 mm, densely silvery-pilose; sepals slightly unequal, sericeous, outer 10-11 × 4-6 mm, ovate, acute, grey-sericeous, the inner sepals c. 6 mm wide. oblong-elliptic, rounded to truncate, the margin scarious and glabrous; corolla 7-8 cm long, funnel-shaped, mauve, sericeous, limb c. 4 cm diam. Capsules and seeds not known.

Illustration.

Figures 15E , 42 .

Distribution.

Endemic to NW Bolivia. This is a local species of moist forest and forest relics in the Andean foothills below 700 m.

BOLIVIA. Beni: Ballivián, east of Puente Quiquebey, J.R.I. Wood 16278 (HSB, K, LPB, USZ); Marbán: San Pablo, J.P. Coulleri et al. 166 (CTES); Cercado, T.C.O. Ibiato, M. Martinez 9 (USZ); Yacuma, Est. Biológica del Beni, E. Gutiérrez et al. 1567 (FTG, MO, USZ). Cochabamba: Chapare, P.N. Isiboro-Sécure, E. Thomas 699 (BOLV, LPB, K). La Paz: Iturralde, Alto Madidi, A. Gentry & S. Estensoro 70653 (LPB, MO, SP); San Buenaventura, A. Fuentes 4387 (BOLV, LPB, MO, USZ); Larecaja, Guanay, H.H. Rusby 1999 (MICH, NY).

Typification.

The syntype from Guanay (NY 00319205) is labelled as holotype but this is not correct. We have selected Bang 2506 (NY00319206) as lectotype as Rusby clearly states that the description of the flowering plant is based on this collection and it is, in any case, a much better specimen.

Note.

This species is morphologically close to Ipomoea megapotamica differing by the acutely 3-lobed leaves and the silvery-grey appressed pilose abaxial surface of the leaves. Coulleri et al. 166 differs in the spreading indumentum of the sepals and the more persistent bracteoles, so approaching Ipomoea macarenensis .

Figures

Figure 15. Photographs of Ipomoea species. A-B I. setosa subsp. pavonii A fruit B flower C I. paludosa, subspicate inflorescence D I. lilloana, storage root E I. opulifolia, storage root, leaves and flower. A, B, D, E Maira Martinez; C Hector Keller.

Figure 42. Ipomoea opulifolia. A habit B stem showing indumentum C adaxial leaf surface D abaxial leaf surface E outer sepal F middle sepal G inner sepal H corolla opened out to show stamens J fruiting inflorescence. Drawn by Rosemary Wise from Wood 16278.