Glasseye: Big Eyes and a Changing Coat

The glasseye is a red bigeye with large, glassy, reflective eyes and a party trick: it can shift from solid red to a silvery, blotched pattern in moments. A shy night fish, it rests in shade by day. Here's how to spot one snorkeling near Jacó, plus five fun facts.

Glasseye · Heteropriacanthus cruentatus

How to spot the glasseye near Jacó

Look into the shaded ledges and recesses of the rocky reef. The glasseye hovers there during the day, its red body and oversized, mirror-like eyes catching what light there is. If it looks blotchy or pale one moment and solid red the next, that's the glasseye doing exactly what it's named for.

5 fun facts about the glasseye

• Eyes like glass. Its large, reflective eyes gather faint light for night hunting — and give the fish both its common name and its startled, wide-eyed look.
• A living mood ring. It can switch between solid red and a silvery, blotched pattern in seconds, often as it moves between shadow and open water.
• A nocturnal hunter. By day it shelters in caves and ledges; at night it comes out to feed on small shrimp, crabs, and little fish.
• Found around the world. Unlike many of our reef fish, the glasseye lives in warm seas across the globe — but it's always a treat to spot one here.
• Rough to the touch. Its scales are notably rough and prickly, part of the sturdy armor common to the bigeye family.

The glasseye is just one of many characters down there. See the whole cast in our Snorkel Jaco fish directory, or read real guest photos and reviews on the Snorkel Jaco reviews.