Aphanotorulus phrixosoma is a dubious species of catfish in the family Loricariidae.

It is native to South America, where it occurs in the upper Amazon River basin.

[1] A. phrixosoma was originally described as Plecostomus phrixosoma by Henry Weed Fowler in 1940, although it was transferred to the genus Squaliforma (now considered invalid) after the genus' designation by I. J. H. Isbrücker, I. Seidel, J. Michels, E. Schraml, and A. Werner in 2001.

[2] In 2004, Jonathan W. Armbruster classified the species within Hypostomus instead of Squaliforma.

This is due to the fact that it was collected in an area where A. horridus and A. unicolor are sympatric, and because extensive sampling efforts near the type locality have yielded no additional specimens.