Use of molecular, morphological, and geographic tools for the description of two new species of Cedrela (Meliaceae, Sapindales) from western Ecuador

Two new species of the genus Cedrela (Cedrela brevicarpa and C. pubescens; Meliaceae, Sapindales) from the western region of Ecuador are described based on an extensive comparative analysis of 67 different individuals. Cedrela brevicarpa is recorded in the humid and semi-deciduous forests along the Northern Coast of Ecuador, spanning elevations from 0 to 900 metres. This species is distinguished by its puberulent or pubescent leaves and peduncles. The inflorescence can reach up to 65 cm in length, while the fruit is ellipsoid or slightly obovoid, measuring 2.4–3 (–3.5) cm long, with a pericarp thickness of < 1.5 mm. Additionally, the columella exhibits five wings attached to attached to a fibrous central structure. Cedrela pubescens, recorded between 1300 and 2400 m in the western slopes of the Ecuadorian Andes, is characterized by its oblong-lanceolate or oblong leaflets, densely pubescent lower surface (with walking-stick-shape trichomes), a cyathiform calyx with five symmetric lobes, and a slightly obovoid and lenticellate (especially at the base) fruit, 4.5–7 cm long. Molecular analyses using nine microsatellite loci revealed a distinct genetic clustering of samples from both new Cedrela species in comparison to their closest taxonomic relatives. This finding supports their classification as a distinct species. To assess conservation status, species distribution models (excluding unsuitable ecosystems, and habitat loss and population reductions) were calculated by overlaying deforestation and vegetation data for the target species. C. brevicarpa is defined as critical Endangered primarily attributed to a staggering 67% loss of its habitat, while Cedrela pubescens is classified as Endangered. Despite contending with deforestation in its native areas, the species benefits from a presence within various state-protected zones on the western Andean flank of Ecuador.