Pterygoplichthys Pterygoplichthyini is a tribe of catfishes (order Siluriformes) of the family Loricariidae.

[1] Pterygoplichthyines are known from nearly the entire range of loricariids except for the Guyanas and coastal streams in southeastern Brazil.

[2] Pterygoplichthyini is sister to the tribe Ancistrini, which shares the derived presence of an evertible patch of plates on the cheek.

[1] The two genera are supported as sisters by only one derived characteristic: a modified stomach that is attached to the abdominal wall by a net of connective tissue.

A white net of connective tissue surrounds the organ, leaving a circular area in the middle of the stomach free; this connective tissue firmly holds the stomach to the body wall and is better developed in adults.