It is grouped with the velvet belly lantern shark (E. spinax), Caribbean lanternshark (E. hillianus), fringefin lanternshark (E. schultzi), broadbanded lanternshark (E. gracilispinis), combtooth lanternshark (E. decacuspidatus), and dwarf lanternshark (E. perryi) in having irregularly arranged, needle-shaped dermal denticles. Etmopterus compagnoi is a questionably valid species as it may be based on the brown lanternshark or Etmopterus baxteri.
Etmopterus compagnoi is a species that shares characteristics with other lantern sharks, specifically the velvet belly lantern shark (E. spinax), Caribbean lanternshark (E. hillianus), fringefin lanternshark (E. schultzi), broadbanded lanternshark (E. gracilispinis), combtooth lanternshark (E. decacuspidatus), and dwarf lanternshark (E. perryi). These shared features include their unique dermal denticles, which are needle-shaped and irregularly arranged.