Abstract: According to the absence of the cerci in both Collembola and Protura, Borner in 1910 grouped them together into a class Ellipura, which has long been supported by many entomologists in the world. As Kukalova-Peck (1987) discussed about the ground plan of the appendages of a fossil Diplura (?), she concludedt hat Collembola and Protura differ in having a more primitive abdominal pleuron which does not include the trochanter, and should be classified as sister groups, (Protura+Collembola) Parainsecta. But the evidences from the comparison in morphology, internal structures, comparative spermatology, morphogenesis and post-embryonic development, as well as the data of the molecular sequences between Collembola and Protura, did not lead to a close relationship. Therefore, the grouping of Protura and Collembola together as a monophylum is not supported. The assemblage Ellipura (=Parainsecta) should be rejected.

Key words: Collembola, Protura, Ellipura, phylogenetic relationship, taxonomic status