Paralithoxus is a genus of suckermouth armored catfishes native to tropical South America.

[4] Paralithoxus species have a unique, enlarged, thin-walled stomach from which the intestine exits dorsally.

[5] Colouration in Paralithoxus species is typically slate gray to tan with a few lighter markings on the body; there are occasionally bands in the pectoral and caudal fins.

[4] Breeding males develop extremely long odontodes on the leading edge of the pectoral fin spine.

The large size and small number of eggs suggest that parental care is well developed, but nothing is known of the breeding habits of Paralithoxus.