Otothyropsis marapoama is a species of armored catfish endemic to Brazil.

Within this tribe, it represents a clade along with the genera Schizolecis, Otothyris and Pseudotothyris, which share unique specializations of the cranium associated with an enlarged swimbladder capsule.

The degree of development of the swimbladder capsule in these genera was not found in any other member of the Otothyrini.

[1] The region where this species is found is one of the most heavily impacted by anthropogenic activities in Brazil, and the lack of previous records of such a distinctive fish suggests a high degree of endemism as well as vulnerability.

[1] These fish have round lips that form a suckermouth with maxillary barbels.