The firefish’s elongated dorsal fin is used to communicate with other firefish. It is also used to lodge itself into small cracks and crevices of a reef. This defense mechanism became part of the firefish’s instincts only after the Fall since before the Fall all animals were vegetarian.


  • The torpedo-like body of the purple firefish is colored light pink near its head and deepens into a deep red or orange at its tail.
  • The upper lobes of the tail are almost black.
  • It has an elongated dorsal fin.

Fun Facts

  • The purple firefish is aggressively territorial against other firefishes.
  • It is sometimes called a dartfish because of its quick swimming style.
  • Several firefishes, particularly juveniles, may utilize the same hole.

CLASS: Actinopterygii (ray-finned fishes)
ORDER: Perciformes (perch-like fishes)
FAMILY: Microdesmidae (dartfishes and wormfishes)
GENUS/SPECIES: Nemateleotris decora

Size: Up to 3 in (7.6 cm)
Depth: 20–200 ft (6–60 m)
Diet: Zooplankton and small crustaceans
Habitat: Indo-Pacific region