Convolvulus ensifolius P.P.A.Ferreira & Sim.

Ferreira, Priscila Porto Alegre, Simão-Bianchini, Rosangela & Miotto, Silvia Teresinha Sfoggia, 2013, Three new species of Convolvulaceae Juss. from South America, Phytotaxa 135 (1), pp. 27-34 : 29-33

Convolvulus ensifolius P.P.A.Ferreira & Sim. -Bianch., sp. nov. [ Figs 2 (A–F); 4(E–G)].

Affinis Convolvuli lilloi , sed ab ea caulibus alatis et foliis glabris et angustibus differt.

Type: — BRAZIL. Rio Grande do Sul: São Francisco de Paula, Tainhas , 29°23'05.4"S, 050°32'05.3"W, November 2009, fl. fr., P . P . A. Ferreira 300 (holotype: ICN; isotypes: K; SP) .

Subshrub, stems short-winged, prostrate, with twining apices, glabrous, milky sap absent. Petiole 0.2–0.6 cm long, glabrous; leaf blade entire, linear-oblong, 2–6 x 0.2–0.4 cm, glabrous, base sagittate, apex acute. Inflorescence axillary, 1-flowered. Peduncle 2.5–6 cm long, glabrous, short-winged; bracteoles lanceolate, 0.3–0.5 cm long, deciduous; pedicel 0.8–1.2 cm long, glabrous, short-winged. Sepals subequal; outer three obovate, 0.6–0.8 x 0.3–0.4 cm, glabrous or sericeous with the margins ciliated, apex obtuse, rarely emarginate, mucronate; inner two obovate to suborbicular, 0.7–0.9 x 0.5–0.7 cm, glabrous, with scarious margins, apex obtuse, rarely emarginate, mucronate. Corolla funnelform, 1.8–2.2 cm long, white, glabrous or sericeous on the exterior. Stamens subequal, included, 0.8–1 cm long, the filaments fused to the base of the corolla tube, glandular pubescent at the base. Pollen tricolpate with microgranulate exine. Ovary subglobose, glabrous, 2-loculed, 4-ovuled; style entire, glabrous, 0.6-0.9 cm long; stigmas 2, filiform, 0.3–0.4 mm long. Capsule 4-valved, 1–1.1 cm long, base of style forming an apiculate apex; seeds 3–4, black, 0.4–0.6 cm long, glabrous, surface foveated.

Distribution and habitat: Convolvulus is essentially a temperate genus, having its most important centers of diversity in East Africa, Central Asia, Arabia and the Mediterranean region. Southern Africa, temperate South America and Australasia also harbor significant numbers of species ( Carine, 2013). The genus comprises about 200 species and eight are found in southern Brazil, occurring in several different environments. Convolvulus ensifolius grows in rocky grassland in Rio Grande do Sul and Paraná states.

Conservation Status: —The existing data are not sufficient to fit it into a category (DD. data deficient).

Paratypes:— BRAZIL. Paraná: Ponta Grossa, Parque Estadual de Vila Velha , próximo à Fortaleza, 25°14'S, 049°59'W, 9 November 2002, R . Gonçalves 16 ( UPCB) . Rio Grande do Sul: Porto Alegre, Arraial da Glória, s.d., Rêrieck 5068 ( MVM); São Francisco de Paula , Tainhas, 29°23'05.4"S 050°32'05.3"W, 5 March 2010, P. P. A . Ferreira et al. 388 ( ICN) .

Convolvulus ensifolius can be distinguished from other species of the genus occurring in South America by the narrowly winged stem, peduncle and pedicel and by the very narrow leaf blades. The most similar species morphologically is Convolvulus lilloi O'Donell (1959a: 293) , which also has solitary flowers. However, C. lilloi has a tomentose indumentum, the stem, peduncle and pedicel are not winged, and the leaf blades are 1–3 cm wide whereas in C. ensifolius they are 0.2–0.4cm wide. Furthermore, the sepals are 1–1.3 cm long in C. lilloi but 0.6–0.9cm long in C. ensifolius .

Ipomoea mirabilis P.P.A.Ferreira & Sim. -Bianch., sp. nov. [ Figs. 3 (A–H); 4(H–K)]. Affinis Ipomoeae lindenii , sed ab ea foliis tomentosis et cimis laxis differt. Type: — BRAZIL. Rio Grande do Sul: Tio Hugo, Arroio Grande , divisa com Vitor Graeff , BR 153 , km 220,

28°36'32.2"S, 052°36'25.2"W, March 2011, fl. fr., P . P .A.Ferreira & J. Durigon 702 (holotype: ICN; isotype: FLOR;

S; SP).

Woody climber, stems twining, tomentose to glabrescent when old, milky sap present. Petiole 5–11 cm long, tomentose to glabrescent when old, apex glandular; leaf blade entire, ovate, 8–15(–25) x 6–10(–18) cm, tomentose on both sides, trichomes denser on the nerves, base cordate, apex acute to acuminate, mucronate. Inflorescence in lax axillary cymes, with 1–15(–30) flowers. Peduncles 1–22 cm long, tomentose to glabrescent; primary and secondary bracteoles linear to lanceolate, sericeous, 0.4–2.2 cm long, deciduous; pedicels 0.4–2.2 cm long, tomentose to glabrescent. Sepals unequal; outer one ovate to suborbicular, 0.6–0.9 x 0.8–0.9 cm, glabrous, with scarious margins, apex emarginate; middle two oblong to orbicular, 1–1.3 x 0.8–1 cm, glabrous, with scarious margins, apex obtuse, mucronate; inner two orbicular, 1.2–1.5 x 1–1.3 cm, glabrous, with scarious margins, apex obtuse, mucronate. Corolla funnelform, 8–10 cm long, with a pink limb and purple throat, glabrous on the exterior. Stamens unequal, included, 2.1–3.2 cm long, the filaments fused to the base of the corolla tube, glandular pubescent at the base. Pollen pantoporate with echinate exine. Ovary ovoid, glabrous, 2-locular, 4-ovuled; style entire, glabrous, 3–3.5 cm long; stigma biglobose. Capsule 4- valved, 1–1.2 cm long, base of style forming an apiculate apex; seeds 2–4, brown, 0.6–0.8 cm long, glabrous, with long trichomes along the margins and apex.

Distribution and habitat: Ipomoea is the largest genus in Convolvulaceae with ca. 600 species and includes erect and trailing herbs, vines and shrubs distributed worldwide ( Miller et al., 2002). Ipomoea mirabilis grows in Subtropical Seasonal Forest, in the States of Rio Grande do Sul and Santa Catarina, Brazil; and in the province of Misiones, Argentina.

Conservation Status: —According to the IUCN Red list ( IUCN, 2001) the species is assessed as vulnerable (VU, subcriteria D1+2) since the population size is estimated to number fewer than 1000 mature individuals and the populations have a very restricted area of occupancy, such that the species is prone to the effects of human activities or stochastic events within a very short time period in an uncertain future due to the introduction of Glycine max (L. 1753b: 725) Merr. (1917: 274) in the species occurrence area.

Paratypes: — ARGENTINA. Misiones: Guaraní , ruta 15, 17 km de la ruta 14, 25 February 1999, F. O . Zuloaga & O . Morrone 6886 ( SI) .

BRASIL. Rio Grande do Sul: Tio Hugo, caminho para Soledade , BR 386 , km 220, 28°36'32.2"S 52°36'25.2" W, 9 January 2011, P. P. A . Ferreira & J . Durigon 607 ( ICN, R); km 207, 16 March 2011, P. P. A . Ferreira & J . Durigon 705 ( ICN, INPA); km 217, 16 March 2011, P. P. A . Ferreira & J . Durigon 703 ( ICN, NY) . Santa Catarina: Descanso , 2 March 1964, R. M . Klein 5119 ( HBR) .

Ipomoea mirabilis is characterized by being a woody vine, with a tomentose leaf blade and lax inflorescences. The arrangement of the sepals is also distinctive: the outermost is very small, with the two intermediates and two inner sepals larger. Ipomoea lindenii M. Martens & Galeotti (1845: 264) , which occurs from Mexico to Bolivia, is the most similar species morphologically but it has glabrous leaves and a very congested inflorescence.

Ipomoea mirabilis resembles I. sulina P.P.A.Ferreira & S.T.S.Miotto (2011: 290) , which occurs in Santa Catarina and Rio Grande do Sul states, but the adaxial surface of the leaves is glabrous in this species, the sepals are larger (outer sepal 0.9–1 cm long, middle sepals with 1.2–1.4 cm long, inner sepals 1.5–1.8 cm long) and the corolla is shorter (5–8 cm long) differing also in its colour since it has a white rather than pink limb.

Figures

FIGURE 2. Convolvulus ensifolius. A. Stem. B. Outer sepals. C. Inner sepals. D. Stamen. E. Gynoecium. F. Seed (A—F: P.P.A. Ferreira 300).

FIGURE 3. Ipomoea mirabilis. A. Stem. B. Outer sepal. C. Intermediates sepals. D. Inner sepals. E. Stamen. F. Gynoecium. G. Capsule. H. Seed (A—H: P.P.A. Ferreira & J. Durigon 702).