Ecuador. • Carchi: cantón Tulcan, parroquia Chical, Cerro Golondrinas, ridgeline(s) between campsite #1 (sector Río Verde) to campsite #2 (La Laguna), 0°52'20.07"N, 78°12'25.61"W, 1800–2225 m alt., 26 Jan 2024, John L. Clark, Luis Micanquer, Milton Cantincuz, Mia Johnson & Nolan Exe 18185 (holotype: QCA; isotypes: F, G, MO, NY, SEL, US).

Vegetatively similar to Columnea suffruticosa J.F. Sm. & L.E. Skog due to the presence of ovate leaves with a rust-colored multicellular hispid indumentum, but differing in the terrestrial habit (vs. epiphytic habit in C. suffruticosa) and deeply bilabiate corolla (vs. uniformly tubular corolla in C. suffruticosa). The deeply bilabiate corolla, dark purple corolla tube, and glandular trichomes throughout the upper and lower lobes are unique characters not found in any other known species of Columnea.

Terrestrial subshrub with dorsiventral shoots, 1.0–1.5 m tall, stems green with densely pilose rust to gold-colored multicellular hispid indumentum; internodes 1.0–2.5 cm long. Petioles 1.0–2.5 cm long, red, with densely pilose to gold-colored multicellular hispid indumentum; leaves opposite, pairs strongly anisophyllous, larger leaf 9.0–15.0 cm long, 4.0–7.0 cm wide, ovate-elliptic, apex acuminate, base rounded and slightly oblique, lateral veins 5–9 per side, adaxially light-green, with multicellular hispid indumentum, abaxially uniformly-red, with multicellular hispid indumentum, more densely pubescent on veins, margin entire; smaller leaf 1.0–2.0 cm long, 0.9–1.5 cm wide, lateral veins 2–3 per side, petiole 1–2 mm long, otherwise similar to larger leaf. Inflorescence reduced to 1–3 axillary flowers; bracts triangular, green, 2–3 mm at base, apex broadly acuminate. Pedicels 1.0–1.8 cm long, dark red, densely pilose with multicellular rust-colored hispid indumentum. Calyx lobes uniformly green or green suffused with red, 1.0–1.7 cm long, 0.5–0.7 cm wide at base, oblong, apex acuminate, exterior pilose, with multicellular rust-colored hispid indumentum, interior glabrous, margin mostly entire or with 1–3 serrations. Corolla 5.0–6.2 cm long, 2.0 cm at widest (apex) point, deeply bilabiate, lower lobe recurved, 1.8–2.2 cm long, 3–4 mm wide, lateral and upper lobes fused into a hood, lateral lobes reflexed, rounded, 5 mm at base with acuminate apex, upper lobes fused, 1.0 cm wide, 1.3 cm long, apex bilobed, each lobe rounded, densely pubescent with multicellular rust-colored trichomes, interior uniformly dark purple, covered with glandular trichomes, occasionally with yellow margins, especially along the lower lobes, outer surface dark purple to dark purple suffused with yellow. Filaments ca. 3.5 cm long, connate at base for 0.3 cm and adnate to corolla, anthers ca. 3.0 mm long, 3.0 mm wide, included in the corolla throat, quadrangular. Ovary ca. 4.0 mm long, conical, glabrescent; style 3.5–4.0 cm long, glabrescent, stigma rounded. Nectary comprised of one large dorsal and two smaller lateral glands. Fruit not observed.

Collected in flower in January.

The specific epithet reflects the type locality, Cerro Golondrinas, where this species is presumably endemic.

Columnea golondrinensis is only known from a single population on a ridgeline in Cerro Golondrinas. The region is protected by the recent acquisition and purchase of forest by Fundacion EcoMinga. The forest corresponds to the Chocó Biogeographic Region for the relatively high levels of precipitation and epiphytic diversity. Based on the available information and according to the IUCN Red List criteria (IUCN 2012; IUCN Standards and Petitions Committee 2024), C. golondrinensis is preliminarily assessed as Vulnerable (VU) based on a limited area of occupancy (IUCN criterion D2 where AOO < 20 km²) and limited number of locations (< 5).

Most Columnea are epiphytic and terrestrial with primary shoots that are characterized as erect, horizontal, dorsiventral (associated with facultative epiphytes), or pendent. The species described here was observed as a multibranched terrestrial subshrub with dorsiventral shoots. It was not observed growing epiphytically and was only observed on a ridgeline with a low canopy and low-growing shrubs where epiphytic diversity was lower. Thus, surrounding forests with higher canopies could host C. golondrinensis as an epiphyte.

Several species of Columnea have purple-brownish coloration on the corolla tube, but these are consistently mostly yellow with narrow bands of horizontal purple-brownish stripes (Fig. 2). In contrast, the corolla color in C. golondrinensis is mostly dark purple to brown with yellow margins on the lower lip. The corolla colors in C. golondrinensis are unique amongst all known members of Columnea.

Corolla lobes in Columnea are always fused and either shallowly bilabiate or nearly radial (Fig. 2C) to bilabiate (Figs 1, 3). The more common form of bilabiate corolla tubes in Columnea is shallowly bilabiate (Fig. 3E, F, H, L) where the lower lip is about the same size as the lateral lobes. The least common form of bilabiate corolla tubes in Columnea is deeply bilabiate (Fig. 3A–D) where the lower lip is half the length of the lateral lobes. The corolla tube in C. golondrinensis corresponds to deeply bilabiate (Fig. 1), the least common corolla form in Columnea. Some examples of Columnea with deeply bilabiate corollas include Columnea karsteniana R.Kr.Singh (Fig. 3A), C. fawcettii (Urb.) C.V.Morton (Fig. 3B), C. tincta Griseb. (Fig. 3C), C. stilesiana M.Amaya & L.P.Kvist (Fig. 3D), and C. strigosa Benth. (Fig. 3K). The presence of dense clusters of glandular trichomes covering the inner surface of the corolla (especially the lower lip) in C. golondrinensis (Fig. 1A) is also relatively uncommon in Columnea. Two species with glandular trichomes on the lower corolla lip include C. karsteniana (Fig. 3A) and C. stilesiana (Fig. 3D), but the glandular trichomes are less apparent and more sparsely distributed. The combination of glandular trichomes on the inner corolla surface (Fig. 1A), deeply bilabiate corollas (Fig. 1B, C), dark purple corollas (Fig. 1), and ovate leaves with rust-colored multicellular hispid indumentum (Fig. 1D, E) are unknown in any other species of Columnea. The combination of these characters are remarkable and support C. golondrinensis as unique and distinct from all other congeners.