New Tree Species, Spirotheca zapotillana, Identified in Ecuador's Dry Forests

A previously unknown tree species, officially named Spirotheca zapotillana, has been formally identified within the seasonal tropical dry forests of southern Ecuador. This significant botanical discovery occurred across the provinces of Loja and El Oro. The initial specimen was documented in the Zapotillo canton on January 15, 2025. This finding carries substantial biogeographical weight, as it effectively closes a hypothesized disjunct distribution gap for the genus Spirotheca, creating an evolutionary link to existing populations found in both Colombia and Brazil.

The comprehensive scientific endeavor, spearheaded by researchers affiliated with the Private Technical University of Loja (UTPL), saw its findings formally published in the journal PhytoKeys on October 31, 2025. The newly described species exhibits several distinct morphological characteristics. These include a strictly arboreal habit, elliptical leaves terminating in sharp points, receptacles on the flowers that possess glands, glabrous styles, elongated capsules, and seeds shaped like small kidneys. Furthermore, observers noted that mature trees frequently grow in clusters, sometimes presenting with three or more clonal offsets. Leaf emergence is timed to coincide with the onset of the rainy season, typically spanning from January through May.

Considering the species' restricted geographical range and the ongoing pressures causing habitat degradation, the research team strongly advocates for classifying Spirotheca zapotillana as Endangered, adhering to the established criteria set by the International Union for Conservation of Nature (IUCN). The estimated Extent of Occurrence (EOO) for this species is approximately 660 square kilometers, while the Area of Occupancy (AOO) is considerably smaller, calculated at only 52 square kilometers. This urgent conservation recommendation underscores the critical need for thorough taxonomic investigation within Ecuador's vulnerable ecosystems.

The dry forests of Ecuador, classified by the World Wildlife Fund (WWF) under the code NT0214, represent an ecoregion already designated as Critically Endangered. This status stems from extensive deforestation driven by agricultural expansion in the western regions of the country, which has resulted in the loss of an astonishing 99% of the original forest cover. The research, conducted by an international consortium involving specialists from institutions such as King Juan Carlos University in Spain and the Institute for Global Change Research in the United Kingdom, offers valuable insight into the evolutionary trajectory of the Spirotheca genus, which encompasses roughly 4,300 species within the Malvaceae family.

Spirotheca zapotillana thrives at elevations ranging from 400 to 900 meters, experiencing pronounced seasonality. This contrasts with some related species that inhabit wetter forests and can reach heights of up to 40 meters. The flowering period for this new species occurs between July and October, followed by fruiting from September through December, which aligns perfectly with the region's dry season. This recent discovery serves as a potent reminder that even rapidly deteriorating environments, such as Ecuador's seasonal tropical dry forests, continue to harbor significant biodiversity that risks being lost before it can even be documented.