Avalithoxus jantjae is a species of armored catfish endemic to Venezuela where it occurs in the Ventuari River above the Tencua Falls. This species grows to a length of SL. It is the only species in its genus.
The generic name derives from meaning "grandmother" and Lithoxus, the genus where it was formerly placed, as an allusion to its basal position. The specific name honours Lujan's mother Jeanne, known as .