Rhynchosia lewisii Bezerra & Fort.

Bezerra, Luísa Maria De Paula Alves, Cândido, Elisa Silva, Vargas, Wanderleia De, Torke, Benjamin Marland, Lewis, Gwilym Peter & Perez, Ana Paula Fortuna, 2024, Taxonomic revision of Rhynchosia Lour. (Leguminosae, Papilionoideae, Phaseoleae) in South America, Phytotaxa 643 (1), pp. 1-67 : 36-37

15. Rhynchosia lewisii Bezerra & Fort. -Perez, Phytotaxa 406 (2): 84–090. 2019. Type:— BRAZIL, Bahia, Santa Teresinha , caminho para a Torre , 12º46’ S 39º31’ W, 16 August 2013 (fl./fr.), M. L. Guedes et al. 20795 (Holotype: ALCB 97782 [!]; isotype: UB [!]). Iconography: Phytotaxa 406 (2): 86. 2019

Vine herbaceous, stems branched, pubescent, indumentum white to light yellow, with yellow vesicular glands and bulbous-based trichomes. Stipules 4–7 × 0.5–1 mm, free, persistent, lanceolate to triangular, externally pubescent with yellow vesicular glands and bulbous-based trichomes. Leaves trifoliolate; petiole 1.9–3.2 cm long; leaf rachis 0.9–1.4 cm long; stipels absent; leaflets 1.9–10.3 × 0.9–4.4 cm, rhombic, lanceolate, or ovate, surface not bullate, acute to attenuate at apex, cuneate to rounded at base, margin entire, pilose, with yellow vesicular glands on the abaxial surface. Inflorescences axillary, paniculate, 8–17.5 cm long, many-flowered, exceeding the length of the subtending leaf; bracts caducous; pedicel 3–5 mm long. Flowers 4–7 mm long excluding the pedicel; calyx 3–4 mm long, densely pubescent with yellow vesicular glands and bulbous-based trichomes, lobes lanceolate to triangular, not exceeding the corolla in length; standard petal 6 × 6 mm, orbicular, rounded at apex, pilose, with yellow vesicular glands and bulbous-based trichomes, claw ca. 2.2 mm long, auricle ca. 1 mm long; wing petals 5.5–5 × 2–2.2 mm, obovate, claw ca. 2 mm long, auricle 1 mm long; keel petals 4.5–5 × 2–2.2 mm, falcate, claw ca. 2 mm long; stamens 7–7.5 mm long; ovary ca. 3 mm long, densely pubescent, with yellow vesicular glands. Fruits 1–2.1 × 1–1.1 cm, greenish, oblong, slightly constricted between the seeds, pilose, with yellow vesicular glands, but lacking bulbous-based trichomes. Seeds 5–6 × 4–5 mm, oblong to obovate, bicolored, yellow to orange and black, areas of coloration almost equal.

Nomenclatural and taxonomic notes: — Rhynchosia lewisii is characterized by the persistent stipules, pedicels 3–5 mm long, fruit slightly constricted between the seeds, and bicolored yellow to orange and black seeds ( Bezerra et al. 2019c).

Reproductive phenology: —This species was collected with flowers in August, September and October, and fruits in August.

Distribution and habitat: — Rhynchosia lewisii occurs in a fragment of tropical forest from Serra da Jiboia, Santa Teresinha, Bahia, Brazil ( Fig. 8 ). The species has only been found in this region, which suggests that it is probably endemic to the state of Bahia ( Bezerra et al. 2019c).

Conservation status: —Endangered (EN). This species was assessed as EN by Bezerra et al. (2019c) following the criteria and subcriteria B2a+B2b (iii) of the IUCN Red List.

Selected Specimens Examined:— BRAZIL. Bahia: Santa Teresinha, Serra da Jibóia, Mata Estacional Semidecidual , 12º50’39” S, 39º28’59” W, 25 October 2010 (fl.), M. L. Guedes et al. 17793 ( ALCB, VIES) ; ibid., ca. de 4 km da Pedra Branca, Mata Higrófila , 12º51’10” S 39º28’32” W, 27 September 2000 (fl.), L. P. Queiroz et al. 6386 ( HUEFS) ; ibid., trilha em área florestada passando as torres de transmissão, 12º51’12” S 39 º28’33” W, 08 October 2018 (fl.), L. C. Marinho 1428 ( HUEFS) .

Figures

FIGURE 8. Geographical distribution of Rhynchosia franciscana and R. lewisii, both species endemic to Bahia state, Brazil.