Differs from all congeners, except Loricaria nickeriensis, by attaining a small adult size, reaching sexual maturity at less than 8.0 cm SL. Distinguished further from Loricaria nickeriensis and Amazon basin Loricaria by the following combination of characters: surfaces of head with prominent crests and predorsal plates with numerous well developed odontodes arranged in conspicuous linear rows; anterior abdominal area covering pectoral girdle naked, with occasional small isolated plates at bases of pectoral fins, pre-anal shield and space between lateral abdominal plates with large polygonal plates; total plates in lateral series 31-32 (modally 31); and post-anal plates 18-19 (modally 18). One specimen from the lower rio Tocantins differs from other collected specimens from the lower Amazon by having a larger eye and maximum orbital diameter of 20.4% HL (vs. 15.4-17.7% HL) and lightly developed iris operculum (vs. absent); and conspicuous pigment pattern consisting of brown blotches on the head and fins with five dark saddles on the dorsum of the body (vs. patterns in Amazon specimens similar, but diffuse) (Ref. 79031).