Piranha have teeth, sharks have teeth, barracuda have teeth, but do your itty bitty tiny goldfish have teeth? Some people are surprised by the answer (which is affirmative by the way). So yes, goldfish do have teeth but they aren't the kind of scary, sharp, fish teeth commonly associated with the terrors of the deep!
The type of teeth goldfish have are called pharyngeal (far-in-jee-uhl) teeth and the reason you cannot see them is because they're not along the "gums" but are located further back inside the mouth in the pharynx. These 'teeth' are not sharp like shark teeth and they're not used for tearing and ripping flesh. The pharyngeal teeth are simply hard projections used primarily to grind up food. If you have your tank filter off and your goldfish is feeding, you can sometimes hear the fish crunching and grinding its food. That is the work the pharyngeal teeth do... and they do it well!
No one exactly knows how many species of cichlids exist in nature but the best estimate is between 1,300 and 3,000 species of fish measuring as small as 2.5 centimeters and as large as a meter in length. I'm sure you'll know some of the fish in the cichlid family like the tilapia, the angelfish, discus and oscar. Goldfish and carp are in the minnow family.
Why Explain Cichlids?
And why am I explaining cichlids? Primarily because this group of fish, like the goldfish, have pharyngeal teeth. These ancient teeth evolved first in the pharynx of jawless fish about a half a billion years ago and predate jaws! (And I'm not talking about Spielberg's "Jaws" here!) Some cichlids have about 3000 teeth total with each single tooth being replaced every 50 to 100 days.
Tooth Loss & Replacement
The same type of tooth replacement occurs with goldfish. Goldfish are in a constant phase of losing and regrowing their teeth. When one tooth falls out, there is another tooth in place, waiting, ready to take its place. The loss of a tooth is not painful for the fish who simply spits it out in the tank when it becomes detached. Sometimes you may even be able to witness this action, and if you don't have a substrate on the bottom of your tank, the discarded teeth are easy to find (they're very flat and look like human molars).
So the next time someone asks you if a goldfish has teeth (it's a question I've been asked at least once a week...just kidding) you'll know exactly how to answer - yes, pharyngeal teeth!
By Tom Matteo