Freshwater Suckerfish

Quick Take

• The fish you call a 'suckerfish' probably isn't the real thing. Three entirely different fish share that name, and the distinctions matter. See the distinct species →
• Suckerfish evolved a single key advantage that lets them feed where other fish simply can't, and this advantage is written right into their name. Explore their evolved advantage →
• Most anglers toss suckerfish back without a second thought, but there's a long culinary history that suggests they're missing out. Discover the culinary history →
• The largest suckerfish species reaches a weight that would shock most freshwater anglers, and its appearance is nothing like what you'd expect. See their surprising size →

Suckerfish belong to the family Catostomidae and live in freshwater environments across the world. It’s believed that suckerfish first evolved roughly 50 million years ago, and today more than 79 species have been identified, though estimates vary. 

Although suckerfish are bony fish, they’ve historically been an important food source and can be found in streams and rivers across not only America, but also other countries such as China. 

Suckerfish are different from the species Hypostomus plecostomus, which is commonly called the ‘suckermouth catfish.’ The species is commonly used in aquariums and is frequently called the ‘janitor fish’ as it cleans algae buildup.  

Remoras are another fish family often colloquially called ‘suckerfish’ thanks to their sucker-like organ that allows them to attach to large marine animals like sharks. 

Classification and Scientific Name

Suckerfish belong to the order Cypriniformes and the family Catostomidae. As of 2026, there are approximately 76 to 78 described species across 13 genera in the Catostomidae family.

Examples of scientific names for specific suckerfish species include:

• Black redhorse: Moxostoma duquesni 
• White sucker: Catostomus commersonii

Types of Suckerfish

With 79 identified species, there is a substantial amount of diversity across suckerfish species. Some of the most well-known include:

• White Sucker (Catostomus commersonii): The white sucker is found in streams and lakes across the Mississippi watershed. Typically, a smaller sucker species weighing little more than 2 pounds, white suckers have occasionally reached sizes of 8 pounds. Thanks to its large distribution, the white sucker is sometimes known as the ‘common sucker.’
• River Redhorse (Moxostoma carinatum): River redhorse is another sucker fish that was once quite common across the Mississippi watershed. However, in recent decades, their range has decreased. While ‘redhorse’ is often synonymous with suckers in local areas, there are several different species with ‘redhorse’ in their name. Other examples include the golden redhorse, silver redhorse, shorthead redhorse, and greater redhorse.
• Blue Suckers (Cycleptus elongatus): Considered Least Concerned by the IUCN. Like other suckerfish, their population appears to be declining due to pollution and dam construction, which have impacted their preferred environments.
• Smallmouth Buffalo (Ictiobus bubalus): These suckers can be found in areas mainly near the Mississippi River and its tributaries. They resemble carp and typically prefer faster-moving water, yet can also be found in lakes. They are closely related to other buffalo suckers.
• Northern Hogsucker (Hypentelium nigricans): These suckers typically inhabit warmer waters with a strong downstream current to provide them with rocks, pebbles, and other particles to scrape nutrients off. The northern hogsucker is not a threatened species and is considered widespread throughout its range.

History and Evolution

While many types of suckerfish live in many parts of the world and have their own specific adaptations, they have all evolved to find ways to procure food where other fish and animals have not.

These different species of suckers evolved because individual members had physical characteristics that allowed them to outlive other members, and these fitter individuals passed their genes on to their offspring over time.

Appearance 

Suckerfish can grow up to about 3 feet (1 meter) long. Most species are between 1 and 2 feet. The largest species of sucker fish is the bigmouth buffalo, which can reach a maximum of 79 pounds (36 kg). For example, the blue sucker is a smaller species, which has an average mass of 5.5 pounds. 

The name ‘suckers’ is derived from their lips, which are thick and help the fish cling to the bottoms of streams and other freshwater habitats. 

Distribution, Habitat, and Prey

The vast majority of suckerfish species live in freshwater streams and lakes across the United States and North America. They can be particularly common in slower-moving channels of rivers or in reservoirs. Outside of North America, fish in the Catostomidae family can be found in Russia, and a single species lives in China. 

Suckers are bottom feeders and live on an omnivorous diet. They’ll consume algae, zooplankton, insects, small invertebrates, crustaceans, and plants.

Predators

Smaller suckerfish are preyed on by larger fish such as trout, bass, catfish, and walleye. Species such as buffalo fish that can reach larger sizes are generally not preyed upon once fully grown.

Fishing & Cooking

Suckerfish were a dietary staple for earlier civilizations, especially across North America, where Native Americans fished for this widely available and abundant species. 

Today, the consumption of suckerfish varies. Smaller species like the white sucker are often used as bait. Larger sucker species must be carefully cleaned to remove bones before being fried. The meat is often described as sweet and flavorful.