Genus: Proplanicoxa CARPENTER & ISHIDA, 2010
Etymology: Greek, pro-, "before" + Planicoxa; in reference to the ilum trending towards the horizontal postacetabular process seen in Planicoxa.
Species: galtoni CARPENTER & ISHIDA, 2010
Etymology: In honor of Peter Galton for his work on European ornithischians.
Holotype: BMNH R 8649
Locality: Southwest coast of Isle of Wight County, England, Southern United Kingdom.
Horizon: Upper half of the Wessex Formation.
Age: Late Barremian Stage, Lower Gallic Subepoch, Middle Early Cretaceous Epoch, Early Cretaceous.
Material: 13 dorsals, sacrum with ilia, parts of pubis and ischium.