A young lionfish in the Red Sea near Dahab

A lionfish is any of several species of venomous marine fish in the genera Pterois or Dendrochirus, family Scorpaenidae. The lionfish is native to the tropical Indo-Pacific region of the world. They are notable for their extremely long and separated spines, and have a generally striped appearance, red, brown, or black on white. While they are available for home aquaria, the venom of the spines is extremely painful, and lionfish are only recommended for the advanced (and careful!) aquarist. As recent as 2003, they have also been spotted in the warmer coral regions of the Eastern Atlantic and Caribbean oceans.

Species called "lionfish":

• Red lionfish Pterois volitans (also peacock lionfish)
• Hawaiian lionfish Dendrochirus barberi
• Plaintail turkeyfish Pterois russelii

Species with "lionfish" in the name:

• Broadbarred firefish Pterois antennata (banded lionfish, spotfin lionfish)
• Radial firefish Pterois radiata (clearfin lionfish, tailbar lionfish, whitefin lionfish)
• Twospot turkeyfish Dendrochirus biocellatus (twinspot lionfish)
• Shortfin turkeyfish Dendrochirus brachypterus (shortfin lionfish)
• Zebra turkeyfish Dendrochirus zebra (dwarf lionfish, zebra lionfish)