The first description of the pupa of Micropsectra borealis (Kieffer, 1922) and a redescription of the imago ♂ is presented. The genus Oeklandia Kieffer, 1922 is synonymised with the genus Micropsectra Kieffer, 1909. The possible synonymy between Oeklandia and the genus Himatendipes Tokunaga, 1959 is indicated. Together with M. coracina (to be treated in a future paper by the senior author) and the atrofasciata-bidentata-group, the species form a monophyletic group within the genus Micropsectra. The pupa of M. borealis shows great variation in the number of lateral setae on the margin of the segments. Often the numbers differ between the two sides of the segment, a state of character not previously reported from the Tanytarsini. The ecology of M. borealis is discussed.