First description of imago and redescription of nymph for Cloeodes irvingi Waltz & McCafferty, 1987 (Ephemeroptera: Baetidae).

The male imago of Cloeodes irvingi Waltz & McCafferty, 1987 is described for the first time based on reared nymphs collected from the state of Pernambuco, northeastern Brazil. It is differentiated from Neotropical congeners, among other characteristics, by the marginal intercalary veins being paired, except between veins ICu1-ICu2 and ICu2-CuP where they are single and between Sc-R1 and CuP-A where they are absent; segment II of forceps with a medial constriction; and the posterior margin of the subgenital plate being rounded. The nymph of this species is redescribed based on new and original specimens. It is differentiated from Neotropical congeners, among others characteristics, by having a labrum with a dorsal arc composed of 2 + 0 + 2 long, spine-like setae, a labial palp segment III that is subquadrangular, and the fore femur with an apex that is not projected, with 2 blunt setae.