Japanese pinecone fish
A marine fish with large, heavy scales resembling a pinecone. Scientific name: Monocentris japonica.
I saw a Japanese pinecone fish at the aquarium.
Kanji spelling is rare; the word is usually written in kana.
From 松毬 (matsukasa, 'pinecone') + 魚 (uo, 'fish'), referring to its pinecone-like appearance.