Amaebi is the translucent, delicate tails of shrimp that are served raw as either nigiri or sashimi. It should not be confused with Ebi, the type of sushi shrimp that are more familiar to the layman: bigger, plainer tasting, always cooked, frequently over-cooked, and which would be disgusting and probably unsafe were it served raw. Amaebi is commonly serves with either Tobiko or Ikura (salmon eggs) on top.
This looks delicious, amazing amebi plating.