Complex sentence: The Ryukyu Wood Pigeon ("Columba jouyi"), otherwise known as the Silver-banded or Silver-crescented Pigeon is an extinct species of pigeon that was endemic to islands in the Okinawa archipelago south-west of the Japanese mainland.
Split into simpler sentences: The Ryukyu Wood Pigeon ("Columba jouyi"), otherwise known as the Silver-banded or Silver-crescented Pigeonis a extinct species of bird in the Columba genus in the Columbidae family. It is an extinct species of pigeon that was endemic to islands in the Okinawa archipelago south-west of the Japanese mainland.