The subfamily Catomerinae represents Southern Hemisphere Catophragmids. This lineage is characterized by a membraneous basis, carinate imbricating plates, and in lacking caudal appendages. One genus, Catomerus is recognized. It possesses ovigerous frenae, and is thus unique among balanomorphs. Ovigerous frenae are characteristic of pedunculate barnacles, while the remaining balanomorphs have ovigerous branchiae.