E Bubocorophium

1. Mandible palp an enormously enlarged, rectangular plate................................. B. macropalpus Just, 2004

- Mandible palp ordinary short with vestigial article 2........................................................ 2

2. Uropod 2 ramus slender, with single apical robust seta only................................................... 3

- Uropod 2 ramus broad with apical robust seta and several robust setae along lateral margin. B. conchicola (Gurjanova, 1938)

3. Gnathopod 2 ordinarily subchelate, propodus posterior margin concave................... B. tanabensis (Harada, 1971)

- Gnathopod 2 nearly oval with weak propodal concavity................................ B. exolitus (Hirayama, 1984)