Burmeistera minutiflora Garzón & F.González, Anales Jard. Bot.

González, Favio, 2023, Taxonomic revision of Burmeistera (Campanulaceae-Lobelioideae) in Colombia, Phytotaxa 615 (1), pp. 1-113 : 63-65

32. Burmeistera minutiflora Garzón & F.González, Anales Jard. Bot. Madrid 69: 244. 2012.

Type:— COLOMBIA. Antioquia: Abriaquí, Parque Nacional Natural Las Orquídeas, vereda Piedras, entre el extremo norte de la cuchilla de Morro Pelao y La Mina, 6°37´N –6°40´N, 76°9´W –76°11´W, 2800–3350 m, 8 Feb 2012 (fl, fr), M. González, A. Duque, W. Galvis, F. Gómez, O. Laverde, M. Londoño, M. Ríos & J. Serna 945 (holotype: COL!; isotypes: HUA!, MA!, NY!). Figs. 17 , 18A–D .

Upright, terrestrial herbs up to 30 cm tall. Stem glabrous. Petiole 3–10 mm long, glabrous; leaf blade ovate, narrowly ovate or elliptic, (1.5–)1.8–2.8(–3.8) × (0.6–)1.0– 1.5 cm, glabrous above and beneath, base slightly asymmetric, convex to rounded, apex acute, margin entire basally, slightly toothed along the distal 1/3–2/3, teeth of one size class, hydathodes 6–10(–16) per side, intramarginal, secondary veins 4 to 6 per side, higher order venation reticulate, intramarginal vein present. Flowers solitary, loosely arranged in the axils of the distalmost leaves. Peduncle 1.8–3.1 cm long, glabrous, ebracteolate. Hypanthium obconic, 2–3 × 3–5(–7) mm, glabrous. Calyx lobes broadly ovate, 1.5–2.0 ×1.5–2.0 mm, patent, glabrous, basally spaced by broad (1.5–2.0 mm wide) sinuses, margin entire. Corolla with tube bright red and lobes bright yellow, glabrous; tube 5–7 mm long, 2–3 mm diameter at its mid- and distal portions, inflated at its base; lobes ovate, slightly falcate, apex acute to shortly acuminate, dorsal lobes 4.5–5.5 × 2.0– 2.5 mm, lateral lobes 3–4 × 1.5–2.0 mm, ventral lobe 4–5 × 1.5–2.0 mm. Synandrium 8.5–11.5 mm long, exserted up to c 1.5 mm; filament tube 6–7 mm long, glabrous; anther tube 2.5–4.5 mm long, glabrous except for the barbate ventral anthers with an apical tuft of white woolly hairs up to 0.5 mm long. Berries obconic, 3–5(–7) mm × 6–8 mm, not inflated, bright red.

Phenology: — Burmeistera minutiflora has been collected with flowers in February, April and September, and with fruits in February, April, September and November.

Distribution, ecology and conservation status: — Burmeistera minutiflora is endemic to a very narrow area in the department of Antioquia, where it has been collected in cloud, high-Andean forests and superhumid páramos and subpáramo remnants of the Western Cordillera between 2800 and 3550 m. Following the IUCN´s (2022) criteria [B1(EOO) and B2(AOO), conditions (a) and (b), and C2(a)(i)], B. minutiflora qualifies as Critically Endangered, mainly due to the extremely low number of flowers per individual, the narrow distribution of the species in fragile, severely fragmented and disturbed subparámo and páramo habitat.

Notes: — Burmeistera minutiflora is easily distinguished by the bicolor (bright red and yellow), small corollas (<1.1 cm long), the smallest in the genus. The flowers of Burmeistera minutiflora are likely entomophilous, as the small, reddish/yellow corollas makes unlikely bat or hummingbird visits. Overall, the species is similar to B. antioquensis , but the corolla alone is similar to that of B. kirkbridei Wilbur , from Panamá. However, the latter species has purple corollas tipped with pink, and its ventral anthers are totally ebarbate.

Additional specimens examined:— Antioquia. Urrao, inspección Jaiperá, vereda El Chuscal, páramo de Frontino, sitio Llanogrande , 3000‒3390 m, 6°27´N, 76°4.6´W, 4 Apr 1989 (fl, fr), R. Callejas et al. 7498 ( HUA) ; Abriaquí, Parque Nacional Natural Las Orquídeas, sector Cuchilla de Morro Pelao (accediendo por La Mina, Río Piedras arriba), 6°37´15.22´´N, 76°9´28.8´´W, 3400‒3450 m, 5 Feb 2012 (fl, fr), M. González et al. 879 ( NY) ; Urrao, páramo de Frontino, El Río, 3115 m, 10–19 Nov 1984 (fl, fr), R. Londoño et al. 365 ( COL, MEDEL) ; Urrao, páramo de Frontino, vertiente oriental, cuchilla de Frontino, 6°30´N, 76°7´W, 3550 m, 10 Sep 2000 (fl), J. Pérez 1514 ( MEDEL) ; Abriaquí, vereda San José, PNN Las Orquídeas, camino de San José a La Quiebra, 6°35´N, 76°10´W, 2980 m, 30 Apr 1990 (fl, fr), J. Ramírez et al. 3874 ( JAUM, MEDEL).

Figures

FIGURE 17. Distribution of Burmeistera microphylla, B. minutiflora, B. multiflora, B. multipinnatisecta, B. mutisiana and B. nigropilosa.

FIGURE 18. A–D. Burmeistera minutiflora (González et al. 945, type), leaves and young berry (A), leaves and flower (B), flower at side (C) and frontal (D) view. E, F. B. multiflora (Luteyn et al. 10674), corymbiform flowering portion of the branch (E), and flower (F). G, H. B. nigropilosa (Luteyn et al. 11700, type), leaves and flower. I, J. B. pinnatisecta (González et al. 2859), flowering (I) and fruit-bearing (J) branches. Photo credits: A–D, M.F. González; E–H, J.L. Luteyn; I, J, F. González. Scale bars: 1 cm in A, E, G, I, J; 5 mm in B, F, H; 2 mm in C, D.