Solanum junctum S. R. Stern & M. Nee

Similar to Solanum subinerme Jacq. and Solanum poinsettiifolium Rusby. Solanum junctum differs from Solanum subinerme in its smaller flowers, shorter cauline prickles and lack of straight prickles on the adaxial leaf surfaces. Solanum junctum has branched inflorescences and lacks the white tomentum on the adaxial leaf surface and the more abundant interpetalar tissue of Solanum poinsettiifolium. Erect or scandent shrub, liana, or small tree, 1–20 m. Stems armed with recurved tan to brown prickles to 5 mm long, the base to 2–4 × 0.5–1 mm, the young stems moderately to densely pubescent with tan to white stellate hairs, the stalks absent to 1 mm, multiseriate, the rays 6–10, ca. 0.5 mm long, the midpoints absent to 0.5 mm, the older stems becoming sparsely pubescent to nearly glabrous. Flowering portions of stem of difoliate sympodial units, the leaves usually geminate, those of a pair often slightly unequal. Leaves simple, the blades 8–12 × 4–7 cm, ovate, chartaceous, green on both surfaces with the adaxial surface typically darker, both surfaces moderately pubescent with hairs like those of the stem, the abaxial surface typically slightly more tomentose and often armed with a few recurved prickles to 2 mm in length on the midrib, abaxial surface with occasional simple glandular hairs below the stellate hairs; venation pinnate, the secondary veins 3–6 on each side of the midvein; base rounded to obtuse, often asymmetrical; margin entire; apex acute to attenuate; petioles 1–3.5 cm, moderately pubescent with hairs like those of the stem, sparsely to moderately armed with prickles like those of the stem. Inflorescence 5–8 (10) cm, extra-axillary, branched with 2–3 (5) main branches, bearing 14–20 flowers, the plants apparently andromonoecious, with male flowers lacking a developed style and hermaphroditic flowers with an elongated style, the axes moderately to densely pubescent with hairs like those of the stem, unarmed; peduncle 2–10 mm; rachis 4–7 (10) cm; pedicels 4–10 mm in flower, 8–14 mm in fruit, spaced 1–3 mm apart, articulated at the base. Flowers 5-merous, appearing actinomorphic on herbarium sheets but slightly zygomorphic in the field due to curved anthers, the flower buds slightly curved. Calyx 0.5–3 mm long in bud through anthesis, cupular with lobes nearly absent, moderately to densely pubescent with hairs like those of the stem, the calyx splitting into lobes during late flowering or early fruiting; fruiting calyx lobes 2–3 × 1–2 mm, triangular. Corolla 2–3 cm in diameter, chartaceous, light violet to purple, lobed nearly to the base, the lobes 8–12 × 2–3.5 mm, narrowly triangular, densely pubescent on the abaxial surface with hairs like those of the stem, glabrous to sparsely stellate-pubescent on the midvein on the adaxial surface. Stamens 8-12 mm long; filaments ca. 0.5 mm long, glabrous; anthers 8–12 × 1–1.5 mm, proximally curving downward with small upward curve at distal end, attenuate, tapering, connivent to weakly spreading, yellow, the base cordate, the apex obtuse, the pores apical, not opening into longitudinal slits with age. Ovary glabrous; style in functionally male flowers 1–2 × ca. 0.5 mm, style in hermaphroditic flowers 12–14 × 0.5 mm, exceeding the anthers by 2–3 mm, cylindrical, glabrous; stigma ca. 0.5 mm wide. Fruit a globose berry 1–1.2 cm in diameter, green, glabrous, held upright, with 3–10 fruits per infructescence. Seeds 75-120 per fruit, 3–4 × 2–3 mm, ovate to reniform, brown.

Known from Amazonas, Ayacucho, Junín, Pasco, and San Martín Departments in Peru from 600–1800 m in elevation. Flowering specimens were collected in February-May, July, November-December and fruiting specimens in April, July-August, November.