31. Burmeistera microphylla Donn.Sm., Bot. Gaz. 25: 146. 1898.

Type:— COSTA RICA. “ La Palma, 1500 m, Nov 1897 (fl), C. Wercklé 11600 (holotype: CR, not seen; isotype US! [US00146946]). Figs. 16D–G, 17 .

Terrestrial or epiphytic herbs or subshrubs up to 2 m tall. Stem glabrous. Petiole 3–8 mm long, glabrous; blade ovate to elliptic, 1.8–3.6 (–6.0) × 0.8–2.6 (–3.8) cm, glabrous above and beneath, base decurrent to rounded, slightly asymmetric, apex acuminate, margin subentire to slightly crenate, with 5 to 10 marginal hydathodes per side, secondary veins 5 to 7 per side, intramarginal vein lacking. Peduncle 2–5 cm long, glabrous, ebracteolate. Hypanthium obconic, 5–9 × 4–6 mm, glabrous. Calyx lobes narrowly ovate, 2–4 × 0.8–1.0 mm, patent, glabrous, basally spaced by sinuses 1.0‒ 1.5 mm wide, margin slightly crenate, with 3 or 4 projections per side. Corolla green to purple, glabrous; tube 7–15 mm long, ca. 2.5 mm diameter at its proximal and mid-level diameter, slightly inflated distally; lobes narrowly ovate, falcate, dorsal lobes 7–8 × 1.6–2.0 mm, lateral lobes 5.8–6.0 × 1.4–1.6 mm, ventral lobe 3.6–4.0 × 1.4–1.6 mm. Synandrium 13.5–19.0 mm long, exserted up to 8 mm; filament tube 10–15 mm long, glabrous; anther tube 3.5–4.0 mm long, glabrous except for ventral anthers that are shortly barbate at the apex during preanthesis and early anthesis. Berries oblate, 6–8 × 9–10 mm, red.

Phenology: — Burmeistera microphylla sets flowers and fruits in February and April.

Distribution, ecology and conservation status: — Burmeistera microphylla occurs in Costa Rica, Panamá, and northwestern Colombia. This species is here reported for the first time in Colombia, where it grows in cloud forests of the Western and Central cordilleras, in the department of Antioquia, at elevations between 1800 and 2500 m. Following the IUCN (2022) Guidelines, it is highly likely that this species is not threatened.

Notes: —The original description of Burmeistera microphylla was based on a single specimen (C. Wercklé 11600), deposited at CR; thus, it corresponds to the holotype. A second specimen, deposited at US, corresponds to an isotype, and not to the holotype, as it is reported in the Jstor Plants platform.

The small-sized leaves of Burmeistera microphylla are superficially similar to those of B. luteynii . However, various traits of B. microphylla indicate a close similarity with B. cyclostigmata, B. cylindrocarpa, and B. marginata, from which it differs by the petiole 3–8 mm long; the leaf blade 1.8–3.6(–6.0) cm long, with 5 to 7 secondary veins per side, but lacking an intramarginal vein; the peduncle 2–5 cm long; the dorsal lobes of the corolla 7–8 mm long; the synandrium exserted up to 8 mm; and the berries oblate, 6–8 × 9–10 mm (versus the petiole (6–)10–30 (40) mm long; the leaf blade> 6 cm long, with 9 to 20 secondary veins per side and an intramarginal vein; the peduncle 5–10 cm long; the dorsal lobes of the corolla 10–17 mm long; the synandrium exserted up to 2.4 cm; and the berries cylindric to narrowly cylindric, 10–20 × 3–10 mm in the remaining species).

Additional specimens examined:— Antioquia. Urrao, sitio el Páramo, entre Encarnación y sector Calles, 1800‒2200 m, 15 Apr 2011 (fl, fr), J. Betancur et al. 15240 (COL, MEDEL); Abriaquí, Parque Natural Nacional Las Orquídeas, vereda Piedras, sitio La Linda (“ La Truchera ”), 6°38´13‒6´´ N; 76°8´0.4´´W, 2500 m, 1 Feb 2012 (fl, fr), M. González et al. 730 (HUA, NY), 755 (HUA, NY), 762 (HUA, NY); entre Yarumal y Valdivia, Alto de La Ventana, 7 Apr 1951 (fl, fr), R. Romero 2320 (COL) .