Species Profile: Cutlips Minnow

As most of you hopefully already know, I am a life-list angler. I target, document, and count the number of species, hybrids, and subspecies I catch, specifically on fly tackle. Because of that I spend a lot of time learning about and fishing for many different species of fish. This means I'm more adept at identifying and fishing for an extremely broad range of species than the average fly angler. This series will attempt to outline species identification, some life history, and methods for targeting with fly tackle. Maybe I'll get to every fish on my life list, but considering it is ever growing... it would take a while. Mostly, I hope this will get a few of you interested in going out and learning about or catching something new. 

Cutlips minnows are one of the most unique freshwater fish in North America. It may not appear to be anything out of the ordinary on first glance, as with most small freshwater fish of it's variety if the average angler caught one they'd just call it a minnow or a dace or a chub and call it a day. But if you get to know Exoglossum maxillingua, you realize how weird this little fish is.

The cutlips minnow has a relatively small range, From extreme northern North Carolina up north along the Atlantic Slope to the St. Lawrence, barely edging into western CT, MA, and VT. Introduced non-native populations exist in close proximity to their native range, where they were most likely released from bait buckets. The species prefers clean freestone streams and resides mostly in slow moving pools rather than riffles and fast water. They may also be found in some lakes. At a glance they don't differ that much from creek chubs in appearance, with an olive colored back, white belly, and frequently well defined lateral stripe, and an average size of about 5 inches. They spawn in the spring around the time most other North American cyprinids spawn. Males build small peddle mounds, similar to the spawning behavior of fallfish but on a smaller scale.

The clearest distinguishing trait of the cutlips minnow, and the one it gets its name from, is its lower lip. The lower jaw of the cutlips minnow consists of three lobes, with the middle one protruding out farther. This is an adaptation that has arisen through utilization of very small mollusks and insects as a food source. Cultlips minnows use their lower lip to scrape tiny snails and nymphs off of stream bed rocks. 

But that is not all cutlips utilize their uniquely evolved mouth for. Oh no. Far from it.

They also use it to pry the eyeballs off of other live fish.

That doesn't sound right, does it? How can that possibly be true? Well, it is. When times are tough, cutlips minnows scoop the eyes out of other fish species and sometimes each other and eat them. A such, they are probably not a great choice for a multi species aquarium. Interestingly, a study done by Antonios Pappantoniou of Fordham University found that "camouflage in the form of eyespots and eye lines did act to either confuse or misdirect the eye-picking attacks of the cutlips minnow." 

So, intriguingly, not only can eye like markings on various fish prevent large predator fish from successfully targeting the head of the prey in question, it can confuse the small, eye-eating cutlips minnow. 

"False eye" exemplified by an adult Cichlasoma urophthalmus

If you want to catch a cutlips minnow on the fly, first of all make sure you are fishing where they exist. The methods are pretty simple. Fish small nymphs in clear pools and look for schools of minnows to cast into. When you catch one, take a close look at its lips to verify that it is indeed a cutlips. Then, marvel at the fact that the little minnow you are holding has one of the most wild and bizarre eating habits of any fish. If you choose to admire fish not only for their size, their coloration, or their edibility, but for their incredible diversity of behavior and anatomy, it opens up a whole new world of fishing to you. Fish are a amazing. That, in the end, is what the "species profile" series is all about.

Until next time.

Fish for the love of fish.

Fish for the love of places fish live.

Fish for you.

Thank you to my Patrons; Erin, David, John, Elizabeth, Chris, Brandon, Christopher, and Shawn for supporting this blog on Patreon.