Euphausiacea
plural noun
Eu·phau·si·a·cea
(ˌ)yüˌfȯzēˈāshēə
: an order of small commonly luminescent malacostracan crustaceans (division Eucarida) related to the Decapoda, resembling shrimps, and in some areas forming an important element of marine plankton
euphausid adjective or noun
(ˈ)yü¦fȯzə̇d
euphausiid
-zēə̇d 
adjective or noun 
Word History
Etymology
New Latin, from Euphausia, included genus (perhaps from eu- + Greek pha- —from phainein to show—+ ousia substance) + -acea