Eastern Mudminnow

Umbra pygmaea

Umbridae · freshwater water fish

4 minute read · Species guide

Eastern Mudminnow field guide illustration

About Eastern Mudminnow

The eastern mudminnow (Umbra pygmaea) is a species of freshwater fish belonging to the family Umbridae. It is native to eastern North America, but has been introduced to Europe. It feeds primarily on insect larvae and other small aquatic invertebrates.

Description

It is an elongated, stout-bodied fish, brown or yellow-green in color, with about 10 or more dark, narrow, lateral stripes separated by pale spaces, although there is no lateral line on the fish. The pelvic fin lies somewhat farther back on the body, such that it rests below the dorsal fin. The body is elongated, and the maximum size of the fish is 15 cm (5.9 in).

Distribution and habitat

The native range of the eastern mudminnow is from New York to Florida, and found as west as Georgia. It has also been introduced to Europe, where it can be found in France, Belgium, Germany, the Netherlands, Denmark, and Poland.

It is generally found in still or slow-moving waters, often in dense vegetation, often over heavily vegetated streams, swamps, and ponds.

The eastern mudminnow has shown great adaptability to poor habitats with low pH, temperature, and presence of oxygen. At least one incident has been documented where an eastern mudminnow has survived an entire night out of water. The fish can be found in waters with a pH ranging from 3.5 to 8.1 in natural environments. The optimal pH for growth is 4.5, which is often detrimental or even fatal for most fish.

Diet

The eastern mudminnow are bottom-feeders and feed on insect larvae, worms, molluscs, and crustaceans.

Behavior

The eastern mudminnows are known to leap from the water while feeding.

Reproduction

Eastern mudminnows have been known to exhibit more complex reproductive behaviors. Males participate in courtship and the fish build nests. Nests can be found in cavities of algae, under loose rocks, and in depressions in the sand. Females guard nests, and males may as well.

During courtship, males will quiver their bodies and show their fins.

North America

In North America, the eastern mudminnow is usually viewed upon with little concern.

Europe

The eastern mudminnow is viewed as a potentially invasive species in much of Europe. The spread of the fish to six European countries in the 20th century is mostly attribute to popularity in the aquaculture and aquarium trades. The presence of eastern mudminnows in Europe can undermine the conservation efforts of vulnerable species such as the european mudminnow. The spread of the eastern mudminnow in these parts of Europe seems to be slow and primarily human mediated (due to usage as live bait or for aquariums).

Article text: Wikipedia contributors, Eastern mudminnow (source revision). Licensed under CC BY-SA 4.0. Retrieved 2026-10-11.

Diet and feeding

The FishTraits compilation records these diet categories for this species: invertebrates or larval fish; larger animal prey (a source category covering fish, crayfish, crabs, or frogs). These are broad categories, not a claim that every individual consumes every example in a category.

Reported feeding positions include bottom feeding and surface or water-column feeding. The compilation combines published observations; diets can vary with age, locality, and available food.

Habitat preferences

Reported habitat associations include streams and small rivers, creeks, still-water habitats.

The source records associations with muck, clay or silt, vegetation, organic debris, large woody material. An association indicates reported use, rather than an exclusive requirement.

Reproduction and parental care

The compilation reports a representative maturity age of 1 years. Its maturity field summarizes mean, median, or modal estimates, usually for females; male estimates can be used when female data are unavailable. It is not a fixed age at which every fish first breeds.

Recorded spawning months are Mar for the source’s reporting region (NC). This is a regional calendar, not a range-wide schedule.

The reproductive-guild classification includes guarding eggs or young at a spawning substrate or nest.

Size and recorded longevity

FishTraits reports a maximum total length of 11.5 centimetres. Some entries use an estimated asymptotic length; this value should not be treated as a certified record catch.

Recorded longevity in the compilation is 4 years. Wild observations were preferred, but captive records were accepted where wild records were unavailable, and unspecified records were assumed wild. The value is not a guaranteed wild lifespan or an aquarium life expectancy.

Range

Where it lives

Share of 2,295 GBIF observation records with a state location, across 13 states. The orange dots are USGS stream-survey sites where this species was caught.
0%
32.8%
Share of 2,295 GBIF observation records with a state location, across 13 states. The orange dots are USGS stream-survey sites where this species was caught.

A blank area on the dot layer usually means nobody sampled there, not that the fish is absent. Turn on “every survey site” to see where the survey looked.

The USGS stream survey caught it at 422 of its sites, in 7 states. That survey and the GBIF records are two different counts of two different things, so the site keeps them apart.

Habitat

Water and movement

Water
WoRMS records this species in fresh water.
Migration
Not migratory

Classification

Taxonomy

Kingdom
Animalia
Phylum
Chordata
Superclass
Actinopterygii
Class
Teleostei
Order
Esociformes
Family
Umbridae
Genus
Umbra
Species
Umbra pygmaea
ITIS TSN
162148
WoRMS AphiaID
154221
GBIF key
5203111

Common questions about Eastern Mudminnow

What is the scientific name of Eastern Mudminnow?
The scientific name is Umbra pygmaea, in the family Umbridae. Classification follows ITIS.
Does Eastern Mudminnow live in fresh water or salt water?
WoRMS records this species in fresh water.
Where has Eastern Mudminnow been recorded in the United States?
GBIF has observations in 13 states, with the most records in New Jersey, North Carolina, Maryland. The map shows observation records, which do not establish the complete natural range.

Closest relatives

Other Umbra species

Same family

More Umbridae