Fat Sleeper

Dormitator maculatus

Eleotridae · freshwater and saltwater and brackish water fish

1 minute read · Species guide

Fat Sleeper field guide illustration

About Fat Sleeper

The fat sleeper (Dormitator maculatus) is a species of fish belonging to the family Eleotridae, known for their flat heads; they are generally found in fresh water, usually found in lakes, ponds and rivers.

Description

Fat sleepers are small fish that have two distinct dorsal fins and scaled, flat heads. Their tails are rounded. They are fully scaled, and their fins are higher up on the body than other species. Their bodies are a darker brown, whereas their dorsal and anal fins are redder in color. They have a dark blue spot around their gill covers.

Distribution and habitat

The fat sleeper is found from the Bahamas and North Carolina to Brazil. It lives in intertidal areas on muddy bottoms, and is more frequent in brackish water. It can be found commonly in freshwater or saline coastal pools and river mouths.

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

Range

Where it lives

Share of 1,175 GBIF observation records with a state location, across 12 states.
0%
33.2%
Share of 1,175 GBIF observation records with a state location, across 12 states.

Habitat

Water and movement

Water
WoRMS records this species in fresh water, brackish water and the sea.
Migration
Migratory
Pattern
  • Diadromous — moves between fresh water and the sea
  • Amphidromous — moves between fresh water and the sea, but not to spawn

Classification

Taxonomy

Kingdom
Animalia
Phylum
Chordata
Superclass
Actinopterygii
Class
Teleostei
Order
Perciformes
Genus
Dormitator
Species
Dormitator maculatus
ITIS TSN
171919
WoRMS AphiaID
159700
GBIF key
2386401
Outside the US
ITIS also files it in Caribbean Territories.

Common questions about Fat Sleeper

What is the scientific name of Fat Sleeper?
The scientific name is Dormitator maculatus, in the family Eleotridae. Classification follows ITIS.
Does Fat Sleeper live in fresh water or salt water?
WoRMS records this species in fresh water, brackish water and the sea.
Where has Fat Sleeper been recorded in the United States?
GBIF has observations in 12 states, with the most records in Florida, Texas, Louisiana. The map shows observation records, which do not establish the complete natural range.

Same family

More Eleotridae