Ampheristus toliapicus was a cusk-eel relative and one of the more unusual deep-bodied components of the London Clay teleost fauna. Ophidiiform fishes are typically elongate, bottom-associated predators, and the anatomy of Ampheristus is compatible with a demersal lifestyle in which small fishes and benthic invertebrates would have been plausible prey. That ecological interpretation is based on its relationships and body organization rather than direct feeding evidence.

The species is valuable because London Clay material includes three-dimensional cranial remains, and related specimens have preserved otoliths in place inside the skull. This rare association links skeletal anatomy with the isolated ear stones that are otherwise common in Eocene sediments, helping to establish how otolith-based and body-fossil records correspond.