6. Burmeistera borjensis Jeppesen, Flora of Ecuador 187: 29. 1981.

Type:— ECUADOR. Napo: Cerro Antisana, 0°30´N, 78´W, 1 mi NE of Borja, 5600 ft, 20 Aug 1960 (fl), P. J. Grubb, J. R. Lloyd, T. D. Pennington & T. C. Whitmore 1339 (holotype: K! [K000250832]; isotype: NY! [NY00467987]). Figs. 5A–C, 6 .

Vines or subshrubs up to 5 m tall. Stem glabrous. Petiole 7‒25 mm long, glabrous to sparsely puberulous; blade elliptic to slightly obovate, 6.5‒15.0 × (2.5‒) 4.0‒ 7.5 cm, glabrous above, glabrous with veins glabrescent to sparsely puberulous beneath, base decurrent to obtuse, apex acute to abruptly acuminate, acumen up to 1 cm long, slightly falcate, margin subentire or irregularly crenate especially along its distal third, with up to 16 slightly extramarginal hydathodes per side, secondary veins 9 to 12 per side, intramarginal vein present, discontinuous. Peduncle 6.0‒ 11.5 cm long, glabrous to sparsely puberulous, ebracteolate. Hypanthium obconic, 5‒10 × 4‒6 mm, glabrous. Calyx lobes broadly ovate, 12‒20 × 8‒11 mm, nearly as long as the corolla, ascending to patent, glabrous, basally contiguous and superposed, margin crenate with up to 8 teeth per side. Corolla pale green suffused with violet or brown, glabrous; tube 1.5‒1.8 cm long, slightly inflated proximally and distally; lobes ovate, falcate, dorsal lobes 13‒15 × 4‒5 mm, lateral lobes 11‒13 × 3.5‒4.5 mm, ventral lobe 10‒12 × 4‒5 mm. Synandrium 3.2‒3.7 cm long, exserted up to 2 cm; filament tube 2.6‒2.8 cm long, puberulous; anther tube 6‒9 mm long, puberulous, ventral anthers ebarbate. Berries subglobose, 2.5‒3.0 × 2.0‒ 2.5 cm, inflated, glabrous, green with brown spots.

Phenology: — Burmeistera borjensis sets flowers and fruits in April, May, July and August.

Distribution, ecology and conservation status: — Burmeistera borjensis occurs in Colombia and Ecuador. In Colombia, it has been found in the Andes of the departments of Huila, Nariño and Putumayo, in well preserved cloud forests at elevations between 400 and 2600 m. Following the IUCN (2022) Guidelines, this species qualifies for the Near Threatened (NT) category.

Notes: — Burmeistera borjensis is similar to B. asclepiadea, B. ceratocarpa, B. rivina, B. serraniaguae, B. smaragdi, and B. succulenta, from which it differs by the calyx lobes broadly ovate, 12‒20 × 8‒11 mm, nearly as long as the corolla (versus the calyx lobes linear-lanceolate, 11–22(–30) × 1–3(–4) mm, shorter than the corolla in the remaining species).

Additional specimens examined:— Huila. San José de Isnos, vereda Mármol, Parque Nacional Puracé, 2600 m, 21 Jul 1980 (fl, fr), G. Lozano 3319 (COL, NY). Nariño. Ipiales, corr. La Victoria, río San Francisco-Río Manizalez, 2400 m, 15 Apr 1992 (fl), B. Ramírez 4843 (PSO). Putumayo. Sibundoy, 8 km abajo de San Francisco, 2200 m, 10 Apr 1992 (fl, fr), E. Hernández et al. 432 (PSO) .