Phylogenetic insights into the Anomopoda, mainly derived from a comparative study of trunk limb 1

Abstract

The P1 in a clade formed by the radopods and daphniid-like families of the anomopods nicely reflects the evolution that has occurred in the order. The Gondwanotrichidae are the only family that has a remnant of an exopodite, but in several other families an exopodite seta is still preserved. The primitive Gondwanothrix has a total of 20 setae on its surface, a number that decreases in the 11 families considered to a minimum of 9 in Moina salina Daday, 1888. Radopods plus Daphniid families are housed in a new suborder, the Mixopoda. The three daphniid families themselves belong in the new infraorder Verripoda. The P1 of the Radopoda has a basal inflexion and a gnathobase; the Verripoda have lost both. Even in the most advanced Mixopoda, the P1 still shows evidence of at least four endite segments. This is no longer the case in the Bosminidae and Ilyocryptidae, which also have ejector hooks in the apical instead of the basal position on the limb. The building blocks of the limb in the latter families are not identifiable. Both families appear old and probably merit to be classified as suborders.