The Sea-Firefly (Vargula hilgendorfii)
➤ It only inhabits coastal waters off Japan.
➤ Rarely grows longer than 3 millimetres.
➤ It has a beautiful transparent shell.
➤ It’s best known for its bioluminescence.
Interesting fact: In World War II, the Japanese collected these creatures and crushed them in sand and water to produce their blue luminescence, which ingeniously served as light for soldiers to read maps and messages at night.