Microsynodontis armatus is a species of upside-down catfish endemic to Gabon where it occurs in the Ivindo River.

[3] However, when examining previously collected specimens from the lower Guinea region that had been identified as M. batesii, Dr. Ng discovered that the specimens actually consisted of nine distinct species, eight of them previously undescribed.

[1] M. armatus is a small fish, reaching a maximum standard length of 2.7 centimeters (1.1 in).

[2] The mouth of the fish faces downward, with broad lips containing papilla.

[4] M. armatus can be distinguished from other members of the genus Microsynodontis by examining the serrations on the pectoral fin spines.