■Stingray

Rays possess a poisonous needle in their tail. They often sit on the sandy bottom, so watch your step. Electric rays can deliver a mean shock.

■Wasp scorpionfish

Nocturnal by nature, wasp scorpionfish by day conceal themselves in the silt. Be careful of your foot placements, since these fish have poisonous spines along their back.

■Sea Catfish

These fish have poisonous spines along their back. Young fry gather in large schools, and these fish live among rock groupings.

■Lionfish

With beautiful, feather-like fins, this eye-catching fish’s poisonous spines are dangerous.

■Devilfish/Stonefish

These fish have poisonous spines along their back. Residing in rocky areas, they completely mimic their surroundings, so be careful when touching rocks.

■Sea Snake

With poison more potent than a cobra, these snakes live in warm waters and, as air breathers, can regularly be seen to surface for air before diving in search of prey.