Fresh AfieldMore posts

Alien Teeth

Mar 05, 2010

Grass Carp 1I recently received some interesting photos of a “jawbone with teeth” found by a Missourian who was out searching for shed deer antlers. The e-mailer was seeking identification of the animal that produced such odd-looking teeth. Not only did the spacing and shape of the teeth look odd but there were a series of parallel grooves on the back side of each one. The teeth were as much a mystery to me as they were to the sender but luckily there are a number of biologists here who I can tap for information. Several indicated that the “jawbone” looked more like the bony parts of a fish than that of a mammal. When I showed them to a biologist in our Fisheries Division, he identified them immediately as the pharyngeal teeth of a grass carp.

Grass Carp 2The grass carp (Ctenopharyngodon idella) is an alien, or exotic, fish species whose native range is coastal rivers of Siberia and China. The genus name is Greek for “comb-like throat-teeth,” so those unusual teeth at the back of its throat gave rise to its Latin name. The species has been widely introduced into North America and is common in the Mississippi, Missouri and St. Francis rivers in Missouri. It has also been introduced into many ponds and lakes for bio-control of vegetation. It is a very large member of the minnow family that, in its native range, can reach a length of 4 feet and a weight of 100 pounds.

Grass Carp 3The adult fish has a preference for aquatic vegetation and has been reported to consume more than its own weight in vegetation in a day. The grooved pharyngeal teeth function to grind the vegetation prior to swallowing. One reason the teeth look so odd to us is that our first inclination is to think of teeth being found only in the mouth area, and those teeth don’t look like any we’ve seen in an animal’s mouth. Now that I know what they are, I don’t think I’ll ever forget them.

Photos by Patrick Winkler, Overland, Mo.

Related Content

Recent Posts

MDC Director Bob Ziehmer and members of the Conservation Commision perform the ground breaking ceremony for the new Busch Shooting Range

Construction on the new Busch Shooting Range has begun

Jun 07, 2016

The new shooting range at the August A. Busch Memorial Conservation Area just took a huge step closer to becoming a reality.  The first dirt has been turned and construction is under way!

The Kids Who Were Afraid of Snakes

Feb 11, 2016

Twin Pines’ Naturalists bring a slithering sign of summer to Willow Springs elementary on a cold winter’s day.

Fly Tying

First Flies

Feb 03, 2016

There's something very special about the first fly you ever tie. It won't be your best, and it might not be your worst, but chances are it will be your favorite.