Denshi Jisho — Online Japanese dictionary

ほたる firefly (Luciola cruciata); lightning bug; glowworm
Common word, Noun, Usually written using kana alone 
きんぼたる Hotaria parvula (species of firefly)
Noun 
つちぼたる glowworm
Noun 
つちぼたる glowworm
Noun 
ひめぼたる Hotaria parvula (species of firefly)
Noun, Usually written using kana alone 

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