Species At Risk

Cutlip Minnow

(Exoglossum maxillingua)


Cutlip Minnow
Cutlip Minnow occurrences map


The Cutlip Minnow reaches 14 centimetres in length. It has a rounded or slightly pointed snout with a downward facing mouth, resembling an overbite. The lower lip has three lobes and appears to be indented in the middle, which is how the species earned its unusual name. The body is olive, brassy or brown-coloured with a whitish belly. Most of the fins are pale or yellowish except the tail and dorsal fins, which may be a red-brown colour.


In Canada, the Cutlip Minnow is found in Ontario and Quebec. Since the 1930s, this species has been recorded at 12 sites in southeast Ontario. However, the most recent surveys have found the Cutlip Minnow at only a few sites in the province.


In Ontario, the Cutlip Minnow lives in warmer rivers and creeks with clear, slow-moving water, and a rocky or gravel bottom. The males dig nests in the gravel where the females lay their eggs. Nests are often found under banks, logs, or around large rocks. The adult feeds on the river bottom and eats aquatic insects.


The main threat to the Cutlip Minnow is habitat degradation. This species likes clean, clear water and does not do well in rivers that are muddy or polluted. Streams can become muddy due to soil washing into the water from nearby urban and agricultural areas. Competition for nest sites with other fish, such as the Common Shiner (Luxilus cornutus), may also be a problem.


The Cutlip Minnow is protected under Ontario’s Endangered Species Act.

What You Can Do to Help the Cutlip Minnow

  • The Ministry of Natural Resources tracks species at risk such as the Cutlip Minnow. You can use a handy online form to report your sightings to the Natural Heritage Information Centre. Photographs with specific locations or mapping coordinates are always helpful. nhic.mnr.gov.on.ca
  • Report any illegal activity related to plants and wildlife to 1-877-TIPS-MNR (847-7667).
  • Invasive species seriously threaten many of Ontario’s species at risk. To learn what you can do to help reduce the threat of invasive species, visit: ontario.ca/invasivespecies ; www.invadingspecies.com ; www.ontarioinvasiveplants.ca ; and, www.invasivespecies.gc.ca .
  • Volunteer with your local nature club or provincial park to participate in surveys or stewardship work focused on species at risk.
  • Private land owners have a very important role to play in species at risk recovery. If you find Cultip Minnow in a watercourse on or adjacent to your property, you may be eligible for stewardship programs that support the protection and recovery of species at risk and their habitats.
  • Farmers and land owners can help improve fish habitat and keep Ontario’s water safe and clean by maintaining natural vegetation next to creeks and rivers, and keeping pollution and soil from washing into Ontario’s rivers. You can find more information about programs and funding assistance for eligible farmers from the Ontario Soil and Crop Improvement Association website at www.ontariosoilcrop.org/en/programs/species_at_risk.htm.

Did you know?

Male Cutlip Minnows build nests to attract a mate. The male digs a depression in the river bottom and clears away any sand or mud. He then carries carefully selected pieces of gravel to line the nest. When a female has laid eggs in the nest, the male covers them with the collected gravel.

Did you know?

The Cutlip Minnow is reported to attack and eat the eyes of other fish, which has earned it the nickname "eye-picker”.

The Endangered Species Act

Contact your local ministry office

Often the best source of local information on species at risk is your nearest ministry office. Call with your questions or concerns.