No.46 Japanese firefly

Japanese firefly is a species of firefly that lives near water and is representative of Japan. Adult fireflies are about 15 mm long and are characterized by their soft black bodies and red thoraxes. At night, they emit a faint, flickering light, creating a fantastical scene. Their most distinctive feature is the “light-emitting organ” at the tip of their abdomen. This organ, which produces light through a chemical reaction, serves as an important signal for males and females to meet, and the rhythm of its flashing also holds significance.

CT scans allow detailed observation of the internal structure of the luminescent body. The interior contains layers that reflect light and tracheae that transport oxygen, which can be clearly seen in the images due to differences in density. The reflective layers in particular contain crystals and are characterized by their bright appearance.

On the other hand, the depression in the center of the abdomen is thought to be caused by the loss of moisture from the body after death, causing the soft tissues to shrink. Fat and digestive organs in particular are prone to drying out and shrinking inside the shell.