Megascolex japonicus Megascolecidae earthworm Amynthas japonicus[2] is an extinct Japanese native probably collected from Nagasaki in the 1820s.

[1] It was one of three native earthworms[3] featured in Dr P.F.B.

von Siebold's extensive collection and recorded as one of Japan's earliest pheretimoid species.

[4] It is now deemed extinct given that a 2018 Nagasaki expedition and earlier 1930s reports failed to locate it.

[5] It is featured on The Recently Extinct Plants and Animals Database.