That's Amore (or A Moray, in this case)

Ocean dwelling, pea green
If he seems a bit mean
That's a moray

With a mouth that won't close
Good for chomping his foes
That's a moray

Hiding in the reef, darting like a thief
Causing lots of grief as he sorts out his dinner

Seabaja.com Isla Tortuga photo Panamic green moray eels

Sharp serrated fangs out from overhangs
Curb his hunger pangs; he emerges a winner

Benthic fish with a wish
For raw crab on his dish
That's a moray

His fierce face from above
Only mothers could love
That's a moray

Check his vomerine teeth
He can hide in their sheath
That's a moray!