Stegophilus
Stegophilus is a genus of pencil catfishes native to South America. Species. There are currently three recognized species in this genus: "S. insidiosus" originates from the São Francisco River basin in Brazil, "S. panzeri" is from the lower Amazon River basin in Brazil, and "S. septentrionalis" is from Orinoco River basin in Venezuela. "Stegophilus" species grow to between 4.1–4.4 centimetres (1.6–1.7 in) SL. "S. insidiosus" is a true parasite living in the gill chambers of larger fishes, including catfishes like "Sorubim lima"; it uses its strong teeth to bite into the gill filaments to suck the blood.