Ipomoea velutinifolia 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 : 29-30

Ipomoea velutinifolia J.R.I.Wood & Scotland Figure 18

Diagnosis.

Ipomoea velutinifolia is apparently related to I. sericosepala J.R.I. Wood & Scotland because of the compound inflorescence and the distribution of the indumentum on the corolla and almost all vegetative parts but differs in the distinctive velvety grey indumentum and in the shape and size of the sepals which are subequal, ovate to suborbicular, 7-8 × 6-8 mm, not unequal, elliptic-obovate, the outer oblong 8-10 × 3-4 mm and the inner 11-14 × 6 mm. The pubescent ovary is a very unusual character in Ipomoea .

Type.

BRAZIL. Maranhão: Mun. Grajau, 4 km W of Mondelandia on path to Rio Grajau , 23 April 1983, E.L. Taylor, C.S. Rosario & J.B.F. Silva 1326 (holotype MG114153 , isotype ARIZ421888) .

Description.

Perennial climber, stems relatively stout, silky-velutinous. Leaves petiolate, 5-9 × 4-8 cm, ovate, apex acute, mucronate, base very broadly cuneate to subtruncate with rounded auricles, margin undulate, adaxially softly and densely pubescent, abaxially velvety-grey; petioles 2.5-4.5 cm, velvety-grey. Inflorescence of compound axillary cymes, these often racemose in form and sometimes distinctly leafy; peduncles 2.5-5 cm, velvety-grey, often extended as a rhachis and reaching 15 cm; secondary peduncles 0.5-2 cm, velvety-grey; bracteoles caducous, not seen; pedicels 10-12 mm, puberulent; sepals subequal, 7-8 × 6-8 mm, outer ovate, obtuse, inner suborbicular, rounded, abaxially velvety-grey, adaxially glabrous; corolla 4.5-6 cm long, sericeous, funnel-shaped, exterior white, interior pale pink; stamens unequal, included, longer c. 2.5 cm, shorter c. 1.2 cm, anthers linear 5 mm; ovary pubescent; stigma not seen. Capsule and seeds unknown.

Distribution and Habitat.

BRAZIL and PERU. Known from the type locality in Maranhão and a single locality at low altitudes in Pasco. Unlike most of the other species in this paper this is a forest species, found in Brazil in the only mature forest relic on a ridge and in Peru in primary forest on white sands. The forest in Brazil was reported to be relatively short with few emergent trees, an open understorey and the presence of many vines in areas where trees had fallen. The distribution (Figure 5 ) is very disjunct but suggests that this species might be found in other suitable habitats around the Amazon basin.

Additional collection.

PERU. Pasco: Oxapampa, Palcazu Dist, San Cristobal, 323 m, 29 May 2008, R. Vásquez et al. 34378 (MO, USM); ibid., Comunidad Nativa Buenos Aires, R. Vásquez et al. 37328 (MO, OXF).

Conservation status.

The two widely separated locations for this species combined with the relatively recent collection dates suggest this species may have been overlooked. No information is available to indicate the plant’s frequency but field notes accompanying the type collection indicate that its forest habitat is threatened. It would be treated as a "black star" species in both Brazil and Peru within the classification of Hawthorne and Marshall (2016), but within IUCN (2012) guidelines it can only be classified as Data Deficient (DD). However, this must be considered only a provisional classification until the populations can be assessed.

Etymology.

The epithet velutinifolia refers to the softly velvety indumentum of the leaves.

Note.

This species appears to be related to I. sericosepala but differs in the subequal sepals and the grey-green velutinous indumentum. It might be interpreted as being related to I. megapotamica Choisy or I. sericophylla but differs from both in the form of the inflorescence and indumentum. From all these species and most others known from South America it also differs in the densely pubescent ovary.

Figures

Figure 5. Map of equatorial South America showing the distribution of Ipomoea cuscoensis (●), I. graminifolia (✖), I. uninervis (▲) and I. velutinifolia (■).

Figure 18. Ipomoea velutinifolia. A habit B adaxial leaf surface C abaxial leaf surface D outer sepal E inner sepal F corolla opened out to show stamens G ovary. Drawn by Rosemary Wise from E. L. Taylor, et al. 1326.