This contribution describes a new species of Brachionus distinguished of the other species of the genus for the presence of two prominent posterior wing-like structures. These structures were previously recorded in Brachionus bidentatus Anderson 1899 var. ambidentatus De Ridder 1991. However, De Ridder assumed that these structures were induced by an environmental factor and then named it as a variety. This work demonstrates that this rotifer deserves species status based on: 1) the general morphology of the female with six anterior spines with a distinctive pattern different to all known Brachionus bidentatus varieties, and the two prominent posterior wings that represent permanent structures in all females (B. araceliae has been cultivated under constant conditions in the laboratory and the wings have been preserved beyond the fifth generation); 2) the morphology of the male of B. araceliae is different of that of the B. bidentatus male
