The Collaborative International Dictionary of English v.0.48:

mangrove snapper \mangrove snapper\ n.
   A fish (Lutjanus griseus) found in shallow waters off the
   coast of Florida; called also gray snapper.
   [WordNet 1.5]

WordNet (r) 3.0 (2006):

mangrove snapper
    n 1: found in shallow waters off the coast of Florida [syn:
         grey snapper, gray snapper, mangrove snapper,
         Lutjanus griseus]