Ipomoea dasycarpa J.R.I.Wood & Scotland, 2017

Wood, John R. I., Munoz-Rodriguez, Pablo, Degen, Rosa & Scotland, Robert W., 2017, New species of Ipomoea (Convolvulaceae) from South America, PhytoKeys 88, pp. 1-38 : 10

Ipomoea dasycarpa J.R.I.Wood & Scotland sp. nov. Figure 6

Diagnosis.

Ipomoea dasycarpa is close to I. verbasciformis (Meisn.) O’Donell but is distinguished by the larger dimensions of the leaves (2.5-11 × 1-3.5 cm, not 3-5.5 × 1-2.5 cm), bracteoles (15-20, not 5-12 mm long) and sepals (14-18 × 5-8, not 10-12 × 5 mm), by the strongly mucronate leaves, acuminate, submucronate (not obtuse) sepals and the comose (not glabrous) ovary.

Type.

BRAZIL. Goiás, P.N. Chapada dos Veadeiros, ca. 1100 m, perto da sede do parque, J.R. Pirani, R.M. Harley, B.L. Stannard, A. Furlan & C. Kameyama 1715 (holotype SPF, isotype K000944456) .

Description.

Erect perennial subshrub to 1 m, rootstock unknown, presumably a xylopodium, stem densely tomentose with white hairs. Leaves very shortly petiolate, 2.5-11 × 1-3.5 cm, oblong to narrowly-oblong-elliptic, margin entire, base cuneate, apex acute, mucronate, the mucro 1.5-2 mm long, often bent, adaxially green, tomentose, abaxially whitish, tomentose, veins prominent; petioles 2-5 mm, tomentose. Inflorescence terminal formed of shortly pedunculate, 3-flowered cymes arising in the axils of the reduced uppermost leaves; peduncles 1-5.5 cm, grey-tomentose; lower bracteoles 15-20 × 4-7 mm, foliose, elliptic, acuminate to a fine point and ± mucronate, tomentose, persistent; upper bracteoles similar, but slightly smaller; pedicels 0-11 mm, tomentose; sepals subequal, outer 15-18 × 6-8 mm, ovate, acuminate, submucronate, tomentose, inner 14-15 × 5-7 mm, tomentose with broad glabrous margins; corolla 4.5-5 cm, funnel-shaped, pink, tomentose in bud, limb c. 4 cm diameter, entire. Capsule 9 × 5 mm, ovoid, muticous, comose with shaggy, somewhat deciduous hairs; seeds 6 × 3 mm, glabrous apart from the fine white marginal hairs c. 5-6 mm long.

Distribution and habitat.

BRAZIL. Endemic to relatively high altitudes between 1000 and 1250 m in the Chapada dos Veadeiros in Goiás, apparently growing in rocky cerrado. Figure 2 .

Additional collections seen.

Goiás: Chapada dos Veadeiros, c. 20 km W of Veadeiros, H.S. Irwin et al. 12407 (FTG114226); 10 km S of Alto do Paraíso, H.S. Irwin et al. 24946a (FTG114228); 18 km N of Alto do Paraíso, H.S. Irwin et al. 32875 (FTG114227); Fazenda de Sao Bento, Glaziou 21786 (P).

Conservation status.

This species has only been found on five occasions, all in the Chapada dos Veadeiros region, indicating this species is very localised in its distribution. Apparently there are duplicates of only one of these collections, suggesting the species is not common in any of the places where it has been found. Field notes are minimally informative. It should probably be treated as Data Deficient (DD) within IUCN (2012) guidelines until the populations can be carefully evaluated. All recorded locations apparently lie within the Chapada dos Veadeiros National Park, which enjoys legal protection.

Etymology.

The epithet " dasycarpa " refers to the comose ovary and capsule.

Notes.

Molecular sequencing using ITS (unpublished data) shows that I. dasycarpa belongs to a large clade of around 70 species almost restricted to South America, which is characterised morphologically by the pubescent exterior of the corolla and the subequal, pubescent, ovate herbaceous sepals. The comose (not glabrous) ovary is an especially interesting character as hirsute capsules are rare in Ipomoea and found outside the Batatas clade in only a few species such as I. sidifolia Schrad. and I. velutinifolia described below. None of these appear to be related to or resemble I. dasycarpa .

Figures

Figure 2. Map of Eastern Brazil and Paraguay showing distribution of Ipomoea attenuata (▲), I. dasycarpa (■) and I. dolichopoda (✖).

Figure 6. Ipomoea dasycarpa. A habit B leaves and stem C adaxial leaf surface D abaxial leaf surface E outer sepal F inner sepal G fruiting inflorescence with fallen bracteoles H apex of capsule J seed. Drawn by Rosemary Wise: A-D from J. R. Pirani et al. 1715, E-F, H, J from H. S. Irwin et al. 32875, G from H. S. Irwin et al. 24946.