Mouth Almighty

(Glossamia aprion)


The mouth almighty is part of the cardinalfish family. This family is primarily marine, but the mouth almighty is a freshwater species typically found in ponds and slow-moving waters of northern Australia. It lurks in dense vegetation, waiting motionless for its next meal. As the name implies, this ambush predator has a large mouth used to engulf any small fish or invertebrate that gets too close.

However, this fish’s cavernous mouth also has a gentler function. When breeding, the male takes up the female’s sack of eggs and incubates them in his mouth for about two weeks—a process known as mouthbrooding. After the eggs hatch, the developing fry will continue to stay in the safety of the male’s mouth for about another week. During this time, the male does not eat.

A Note From the Caretaker

If you look closely at the mouth almighty here at the Aquarium, you will probably see a few individuals with very full-looking mouths, holding eggs or developing fry.

Quick Facts

Learn more about the mouth almighty! Did you know that males of this species incubate eggs and hatchlings in their mouth?

Coastal drainages in northern and northeastern Australia, from the Fitzroy River to Mackay in Queensland.

Its large mouth allows this predator to ambush and swallow crustaceans, small fish and insects.

These fish are approximately 4 to 6 inches long.

The mouth almighty is common in its range.

Larger fish as well as large reptiles and birds prey upon mouth almighties.

Meet the Expert Ken Howell

As the curator of the Upland Tropical Rain Forest, Amazon River Forest and Australia: Wild Extremes exhibits, Ken starts his day early, walking through each exhibit.

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