Ipomoea scopulina 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 : 25

Ipomoea scopulina J.R.I.Wood & Scotland sp. nov. Figure 15

Diagnosis.

Amongst Brazilian species of Ipomoea , I. scopulina resembles only I. longistaminea O’Donell and I. ana-mariae L.V.Vasconcelos & Sim.-Bianch in having a cylindrical suburceolate corolla but is distinguished from both of these by the broadly lanceolate subacute (not oblong-elliptic, coriaceous, somewhat concave) sepals.

Type.

BRAZIL. Espirito Santo, Pancas, Pedra da Colina , 19°13'51"S 40°52'35"W, 700 m, D.P. Saraiva, J. Silva, K.V. Hmeljeviski & R.C. Forzza 47 (holotype RB 00591205) .

Description.

Liana of unknown height; stems woody, pale grey, glabrous. Leaves petiolate, 4-7 × 3-5 cm, ovate, shortly acuminate, base cordate with rounded auricles, margin undulate, adaxially glabrous, abaxially paler, somewhat reticulate, the main veins obscurely puberulent; petioles 1.5-2.5 cm, glabrous or obscurely puberulent upwards. Inflorescence borne on woody branchlets, the axillary cymes subracemose in form, apparently arising after the leaves have fallen; peduncles 6-7 mm long, somewhat woody, glabrous apart from a few scattered hairs; bracteoles deltoid, c. 1 mm long, glabrous, caducous; secondary peduncles 2-7 mm long; pedicels 6-10 mm long, glabrous; sepals slightly unequal, outer 6-7 × 3-3.5 mm, broadly lanceolate, subacute, glabrous, margin scarious, inner similar but obtuse and with broader scarious margins; corolla suburceolate, glabrous, reported to be “white”, 3.5-4 cm long, tube subcylindrical, c. 4 mm wide at base, widened to 10 mm in the middle, constricted upwards, c. 6 mm wide at mouth, lobes broadly ovate, c. 2 × 3.5 mm; filaments 1-1.5 cm long, glabrous except for pilose base, anthers linear, c. 2.5 mm, included; ovary presumably bilocular, glabrous, style c. 2.2 cm, stigma bi-globose. Capsule and seeds not seen.

Distribution and habitat.

BRAZIL. Endemic to Espírito Santo state and only known from the type collection. It was found growing in deciduous forest amongst rock outcrops on the Pedra de Colina granite “sugarloaf” inselberg which is a feature of the country around Pancas. Like I. fasciculata described elsewhere in this paper, this is one of a number of Ipomoea species described from Bolivia and Brazil from granite inselbergs. It is to be hoped that I. scopulina will be found elsewhere in the same region or in similar habitats, perhaps at a considerable distance from the type locality. Figure 9

Conservation status.

In the absence of other collections or any information about its frequency the status of this species can only be classified as Data Deficient (DD) within IUCN (2012) guidelines. It would be treated as a "black star" species within the classification of Hawthorne and Marshall (2016), but again this must be considered as a provisional classification as no systematic search has been made for the species at the type locality or in other similar habitats in the area.

Etymology.

The epithet scopulina refers to the cliff-like sides of the granite mountain on which this species was found.

Notes.

The relationships of this species are not obvious but species of Ipomoea with tubular suburceolate corollas are generally rare in the genus and especially so in Brazil. The only two comparable Brazilian species are I. longistaminea and I. ana-mariae . Both have oblong-elliptic, coriaceous, somewhat concave sepals very different from the broadly lanceolate subacute sepals of I. scopulina , almost certainly indicating they belong to different clades. Additionally, I. longistaminea differs in its strongly exserted stamens, truncate-based, tomentellous leaves while I. ana-mariae differs in its oblong-elliptic cuneate-based (not ovate, cordate) leaves.

Like I. longistaminea , I. scopulina appears to be partially deciduous at anthesis. This may be significant as several species with a subcylindrical corolla from Cuba ( I. praecox Wright) and Mexico ( I. tehuantepecensis L. Torres, R. Torres, M.P. Ramírez & J.A. McDonald, I. concolora Matuda) are often leafless at anthesis.

Figures

Figure 9. Map of Eastern Brazil showing distribution of I. ensiformis, I. fasciculata, I. kraholandica, I. longirostra, I. revoluta, I. scopulina, I. veadeirosii, and I. walteri.

Figure 15. Ipomoea scopulina. A habit B leaf C outer sepal D inner sepal E corolla opened out to show stamens F ovary and style. Drawn by Rosemary Wise from D. P. Saraiva et al. 47