Tokyo bitterling
A species of freshwater fish (Tanakia tanago) native to Japan. The name is usually written in katakana as ミヤコタナゴ.
The Tokyo bitterling is designated as an endangered species.
Rarely used kanji form; the word is usually written in kana.
The name likely combines 都 (miyako, 'capital') and 鱮 (tanago, 'bitterling'), referring to a bitterling found in the Tokyo area. The exact historical derivation is uncertain.