Happy Valentine’s Day From this Big, Red, Heart Jelly!

Habitat: deep sea; first collected in the Pacific Ocean off the coast of San Diego
Status: Data Deficient

I could think of no better Valentine’s Day inspired animal than the Bloodybelly Comb Jelly (Lampocteis cruentiventer). While its name might not be the most romantic-sounding thing you’ll hear all day, I hope you can see why I chose to feature it today of all days. It looks just like a big red heart!

These deep sea heart jellies come in a variety of shades of red but their stomachs are always blood red. Scientists believe the red belly allows the creature to mask any bioluminescent prey it eats because, after all, an animal with a bright, glowing stomach would probably make quite the target for predators.

To our eyes, it might seem that a bright red body would also catch unwanted attention but that’s not the case. In the darkness of the deep sea, the red appears to be black, allowing the bloodybelly comb jelly to become almost invisible in the deep, dark water.

The rainbow lights it produces are due to light diffracting from tiny transparent, hair-like cilia. These beat continuously, propelling the heart jelly through the water. Bloodybelly Comb Jellies can be found at depths of 984 to 3,320 feet and only grow to around 6 inches in length. What a beauty, huh?