Idaholanx fresti, the Banbury Springs limpet or Banbury Springs lanx, is a rare species of freshwater snail, an aquatic gastropod mollusc in the family Lymnaeidae.

[1] This freshwater limpet is endemic to the US State of Idaho, where it is known from a 10-kilometer stretch of the Snake River.

[2] Idaholanx fresti lives in fast flowing, clean, cold water springs.

[3] In 1992 it was federally listed as an endangered species of the United States.

It is threatened by habitat modification, spring flow reduction, groundwater quality, and invasive species.