The opening shot of Revenge of the Creature
A figure of gill-man
Gill-man was a monster featured in the 1955 Earth movie Revenge of the Creature.
Rain Robinson had a figure of the gill-man on display in her office at the Griffith Observatory. (VOY: "Future's End")
In early 2377, Tom Paris and B'Elanna Torres witnessed the creature while watching Revenge of the Creature with their 3D glasses on in a recreation of Chicago's Palace Theater on the holodeck. (VOY: "Repression")
The gill-man, described by the Star Trek Encyclopedia, 4th ed., vol. 1, p. 305 as an amphibious humanoid, first appeared in the Universal International produced film Creature from the Black Lagoon in 1954. It further appeared in a third movie in the series, The Creature Walks Among Us, in 1956.