1. Body completely covered by plates .......................... Loricariidae (2)

2'. Tall body, moderate or high caudal peduncle ................................. 5

5 ’. Scapular waist covered by plates ventrally; medium or large adult size .......................................................................................................... 6

6 ’. Less than 10 rays in the dorsal fin ................................................. 7

7 ’. Presence of eversible hypertrophied odontodes in the preopercus ...................................................................................................................9

9 ’. Adipose fin present, abdomen without plaques, short supracleitral pterotic .................................................................................................. 10

10 ’. Muzzle with plates; absence of fleshy tentacles on muzzle ..... 11

11 ’ Dental and pre-jaw teeth of different sizes .................................. 28

 28. Dental teeth larger than those of the premaxilla ........................ 29

29 ’. 2 to 5 teeth in the dental; large teeth ........................................... 32

32 ’. Dark fins with light spots all along .............................................. 33

33. High head, with lateral profile of the acute head (most truncated snout); low caudal peduncle .............. Scobinancistrus pariolispos

Scobiancistrus pariolispos is distributed in the Tocantins and Tapajós rivers while Scobinancistrus aureatus is endemic to the Xingu - PA river.

The presence of a fully inverted operculum and non-orange ray-shaped fin extending along adipose tissue differ from Scobiancistrus pariolispos from Scobiancistrus aureatus.