Barreleye Fish - Definition, Examples, Quiz, FAQ, Trivia
Discover the deep-sea fish with a see-through head and rotating eyes!
What is a Barreleye Fish?
The barreleye fish (scientific name: Macropinna microstoma) is one of the ocean's most mysterious creatures! This deep-sea fish has a completely transparent head that looks like a clear dome. Inside this dome are its eyes, which are shaped like green tubes pointing upward.
Barreleye fish live in the mesopelagic zone of the ocean, about 600-800 meters (2,000-2,600 feet) deep. At these depths, it's almost completely dark, with only faint sunlight filtering down. The barreleye belongs to the Opisthoproctidae family of fish.
Discovery Fact!
Scientists first discovered the barreleye fish in 1939, but it wasn't until 2004 that they saw a live one with its transparent head intact!
How the Barreleye Fish Lives
The barreleye fish has amazing adaptations for living in the deep ocean darkness:
Rotating Eyes
Its tubular eyes can rotate inside its transparent head to look upward or forward
Hunting Technique
It looks upward to spot prey silhouetted against faint sunlight
Special Vision
Green pigments help filter out sunlight to see bioluminescent prey
Stealth Approach
It swims slowly and quietly to sneak up on jellyfish
Feeding Strategy
Rotates eyes forward when eating to guide food to its mouth
Barreleye fish mostly eat small creatures like zooplankton and jellyfish tentacles. Their flat, horizontal fins help them stay almost motionless in the water while they look for food. Their small mouth suggests they eat small prey items.
Deep-Sea Vision!
The barreleye's eyes are so sensitive that they can detect faint silhouettes of prey against the tiny amount of sunlight that filters down to these depths.
Why the Barreleye Fish is Special
The barreleye fish has some incredible features that make it one of the ocean's most fascinating creatures:
Transparent Head
The fluid-filled dome protects its eyes while allowing it to see directly above
Rotating Eyes
Its tubular eyes can swivel to look in different directions
Specialized Vision
Eyes detect both faint sunlight and bioluminescent light
The transparent head dome is filled with fluid, which protects the eyes while still allowing them to gather light. Scientists think this adaptation gives the barreleye several advantages:
• Allows it to see prey directly above its head
• Protects its sensitive eyes from stinging tentacles of jellyfish
• Creates a streamlined shape for swimming in deep waters
• Helps it remain hidden from predators below
Deep-Sea Quiz
Test your knowledge about the amazing barreleye fish with this quiz! Answer all 5 questions to see how much you've learned.
Frequently Asked Questions
Here are answers to common questions about the barreleye fish:
Fun Barreleye Fish Trivia
Discover some amazing facts about these deep-sea creatures!
Deep-Sea Explorer
The barreleye was first discovered in 1939, but scientists didn't see a live one with its transparent head intact until 2004!
Super Vision
The barreleye's green-tinted eyes filter out sunlight, helping it spot the bioluminescent glow of jellyfish and other prey.
Family Ties
There are at least 9 different species in the barreleye fish family (Opisthoproctidae), each with slightly different adaptations.
Pressure Proof
Barreleye fish live under water pressure 80 times greater than at sea level! Their bodies are specially adapted to survive these conditions.
