Propebela diomedea was created in 1944.
Propebela diomedea was created in 1944.
Elysia diomedea was created in 1894.
Diomedea exulans
Diomedea exulans
The genus (always capitalised) is the first part of a scientific name. The plural is genera.
Take the example Diomedea exulans, the Wandering albatross - in this case Diomedea is the genus!