Plectrochilus is a genus of pencil catfishes native to South America.
There are currently three recognized species in this genus:
P. diabolicus and P. machadoi are found in the Amazon River basin in Brazil and Peru, while P. wieneri is found in the Napo River basin of Ecuador.[1]
P. diabolicus grows to 4.8 centimetres (1.9 in) SL. P. machadoi grows to 9.3 cm (3.7 in).
Specimens of P. machadoi have been found partially buried in the belly of a specimen of Pseudoplatystoma where it apparently had burrowed through the body wall.