Allopseudaxine is a genus which belongs to the phylum Platyhelminthes and class Monogenea; all its species are parasites of fish.

Species of Allopseudaxine are ectoparasites that attach themselves as larvae to the gills of fish, and grow into their adult stage.

This larval stage is called oncomiracidium, and is characterized by free swimming and cilia.

[1] The name Allopseudaxine is composed of the prefix Allo meaning different, and a root Pseudaxine, a gastrocotylid monogenean.

With this shape, they superficially resemble gastrocotylid monogeneans like members of Pseudaxine or Allogastrocotyle.