Espeletia saboyana (Millerieae, Asteraceae), a New Critically Endangered Caulirosula from Cordillera Oriental, Colombia

Abstract

Abstract Espeletia saboyana, a new species from Páramo de Saboyá, Boyacá department, Colombia, is described and illustrated. It is a caulescent rosette up to 5 m tall, with whitish-cinereous appearance, sessile leaves with elliptic laminae, cymose capitulescences with aphyllous unbranched portion and 3–5 capitula, 5–13 phyllaries, the external ones 17.4–26.0 mm long, 49–92 ray florets 13.0–18.4 mm long, and 162–347 disc florets 8.2–12.2 mm long. Espeletia saboyana is similar to E. incana, but with longer laminae, bigger foliar area, and fewer ray floret series. It is also similar to E. murilloi, but with longer ray tubes, ray paleae, disc corollas, disc styles, disc anther appendages, and disc paleae. In addition, E. saboyana is distributed allopatrically in regard to E. incana and E. murilloi. This species is informally proposed to be listed as IUCN Critically Endangered (CR), since it is restricted to a single population with extent of occurrence = 1.83 km2 and area of occupancy = 0.48 km2. Besides, this population is severely fragmented into 40–50 demes, the largest one covering only 34,000 m2. Most demes are found in humid soils and wetlands submitted to continuous habitat deterioration as water is drained for use in agriculture. Espeletia saboyana is rare or absent in these newly drained areas, which are either colonized by other species that thrive on drier soils or transformed into pastures for cattle grazing. Furthermore, analyses of size class distributions show that recruitment rates of E. saboyana are significantly lower in small demes, which, if not reversed, can further reduce population size in the near future.