Forestiera ecuadorensis, a new tree species endemic to tropical dry forests of the province of Guayas, western Ecuador, is described; it is a new generic record for that country. It is closely related to the Mesoamerican-Caribbean Forestiera rhamnifolia and Forestiera eggersiana from the Virgin Islands, Haiti and Puerto Rico, but it differs from both of these by having longer leaf blades, with distinctive long-acuminate apices, more lateral secondary veins per side and stamens with shorter filaments. A key to all species presently known from Ecuador is also included.