Ecuadendron acosta-solisianum D. A. Neill (Fabaceae-Caesalpinioideae): A rare and highly endangered species of tree of western Ecuador

The present study reports the rarity of Ecuadendron acosta-solisianum, a newly described species of tree endemic to lowland coastal Ecuador.; Ecuadendron's population size was estimated by using transects of variable area at Churute 1, Churute 2 and Manta Real study sites in southwestern Ecuador. The species geographic distribution was hypothesized applying an ecological-niche model, DOMAIN, based on georeferenced points from fieldwork and from herbarium specimens. Four climatic variables were used to the prediction model. Habitat specificity was analyzed in light of soil components where soil factors were examined using an ordination technique, Principal Component Analysis (PCA).; On the other hand, reduction in population size and spatial distributional range was inferred from estimations of habitat loss where Geographic Information Systems (GIS) tools and Land Use/Land Cover (LU/LC) data were combined.; Despite the fact that Ecuadendron was found in low abundance (<1 ind./ha) at all of the study areas, this research adds one more population and 6 sub-populations found within a wider elevational range, to its previously known distribution. The species distribution model does not suggest Ecuadendron occurrence in a region different from coastal Ecuador. However, when the same distributional model was applied to a surrogate species, Carapa megistocarpa, it is likely that the environmental conditions in the Amazon region may be also suitable for Ecuadendron's Occurrence. Hence, Carapa megistocarpa predictive model was used here to suggest areas for future surveys. (Abstract shortened by UMI.)...