In Japan, fireflies are called hotaru (ほたる) and they’re a summertime insect just like in the U.S. Although about 40 different firefly species live here, Genji and Heike fireflies are the most popular.

Luciola cruciata
Unlike U.S. fireflies, these two species have an aquatic larval stage, so they are commonly found around rivers and streams (Genji fireflies) or rice-fields (Heike fireflies). They’re so popular they even appear on stamps & manhole covers!

Moriyama manhole cover

Genji firefly stamp