A huge family of fish, the Eleotridae are also known as sleeper gobies. These fish are found in several countries and prominently in the Indo-Pacific.
Some species are found in the temperate and tropical regions of the Atlantic coast and warmer parts of America while other species are spotted in the freshwaters of Hawaii Island and New Zealand. Some species are also found in wells, sinkholes, marine, and brackish water.
Species such as the Gobiomorus dormitor also known as bigmouth sleeper, Dormitator maculatus or fat sleepers, Kimberleyeleotris hutchinsi, and many more are included in the family Eleotridae. The size varies according to the species, the average size of the fish is 7.8-35.4 in (20-90 cm). Many of the species are brown while others are white in color.
Eleotridae sleepers are known for their enlarged bodies with rough-edged scales. They have separated pelvic fins, unlike the Gobiidae fish. These fish have conical teeth and many species also have well-developed swimming glands.
Some of the species of the Eleotridae family are listed as Least Concern while the conservation status of other fish has not been evaluated yet. Also, a report of 1994 suggests that around 16 species of the family are either vulnerable or on the verge of extinction.
Keep on reading to learn more interesting facts about the Eleotridae. If you want to know more exciting information about different animals, check out the black ghost knifefish facts and anglerfish facts.
Eleotridae Interesting Facts
What type of animal is an Eleotridae?
The Eleotridae is a family of fish. The family consists of more than 34 genera and 180 species of fishes. These fish are carnivores and primarily prey on small fishes, insects, crustaceans. The species are found almost all over the world.
What class of animal does an Eleotridae belong to?
Sleeper gobies belong to the class of Actinopterygii. Prominent species of the family are Gobiomorus dormitor, Dormitator maculatus, Kimberleyeleotris hutchinsi, and many more.
How many Eleotridaes are there in the world?
The exact population of the Eleotridaes fish is not known as of now as the family is divided into 34 genera. The population of some of this species is declining due to several factors such as pollution, human exploitation, diseases, while the others are out of danger.
Where does an Eleotridae live?
The species of the sleeper gobies family are widely distributed throughout the world. These fish are primarily found in the Indo-Pacific region, while others are spotted in American countries such as the United States, Canada, and Mexico. These fish are also found in New Zealand and numerous countries of the African continent.
What is Eleotridae's habitat?
While talking about the distribution, several species primarily live in the temperate and tropical regions. Others such as the Gobiomorus dormitor live in freshwater and brackish water. Sometimes wells also serve as the Eleotridae habitat.
Who do Eleotridaes live with?
Almost every species of sleeper gobies prefer to live in groups but a few solitary fish come in pairs during the breeding season.
How long does an Eleotridae live?
The exact lifespan of the species of the Eleotridae family is not known but the fish of a similar family known as Gobiidae generally live up to 1-2 years.
How do they reproduce?
The species either follow the process of monogamy or polygyny while some even are polygynandrous. Before breeding, the male fish generally construct nests where the females will deposit the eggs.
During the breeding season, the ventral or the lower region of the females enlarges. Also, the breeding season varies as per the species, in warmer regions, the fish mate for more than once, unlike the colder regions.
The fish are also involved in several courtship displays, like the male swimming around the nesting sites to attract females and try to touch the females with the snout. The females lay around 500-3000 eggs in each season.
Unlike other species of freshwater, the male fish guard the nesting sites. Also, young fish generally live with their parents for some time after the hatching of eggs.
What is their conservation status?
Some of the species of the Eleotridae family are listed as Least Concern while the conservation status of other fishes has not been evaluated yet. Also, a report of 1994 suggests that around 16 species of the family are either vulnerable or on the verge of extinction.
Apart from predators, several factors such as pollution, human exploitation, diseases are causing an adverse impact on the population of the family.
Eleotridae Fun Facts
What do Eleotridaes look like?
Eleotridae sleepers are known for their enlarged bodies with rough-edged scales. They have separated pelvic fins, unlike the Gobiidae fish. The fish have conical teeth and many species also have well-developed swimming glands.
The peacock gudgeon (Tateurndina ocellicauda) is one of the beautiful and vibrant species of the Eleotridae family. Their body is blue in color with silver, pink, black, and yellow marks. The lower part of the body is yellow with red stripes.
How cute are they?
Unlike other fish, many of the species of the family are not considered very cute but the fat sleepers or Dormitator maculatus are often kept by people as pets. Also, the different body movements and nudging each other would be really fascinating to watch.
How do they communicate?
These fish follow the same methods of communication with each other. The body color of male fish generally changes during the breeding season that indicates competition and danger to competitors or other potential male fish.
These fish are known for their rare eyesight as they generally find food and threats from a long-range. Also, these fish try to communicate with their partners through several courtships displays. The species can also detect threats through the sense of smell.
How big is an Eleotridae?
The Eleotridae size varies, some species are small while some could be really large. Species such as the Gobiomorus dormitor or bigmouth sleeper of the West Atlantic region are around 35.4 in (90 cm) long while the length of the fat sleeper (Dormitator maculatus) is 27.5 in (70 cm).
Many of the species are even smaller. Thus the average length of the fish is 7.8-35.4 in (20-90 cm). Some of them are twice the size of the garfish and ten times bigger than the mudfish.
How fast can an Eleotridae swim?
The exact speed of the species of the Eleotridae family is not known and as the name suggests, sleeper gobies species generally do not move and remain only at one place waiting for their prey. Also, many species have swimming glands.
How much does an Eleotridae weigh?
The weight of the Eleotridae fish is not known.
What are the male and female names of the species?
There are no specific names given to male and female fish of the Eleotridae family. Male fish are able to change the color of their bodies, unlike females.
What would you call a baby Eleotridae?
People often refer to the baby of the Eleotridae fish or the newly hatched fish as a fry.
What do they eat?
These bottom-dwelling fish primarily prey on small fishes, insects, crustaceans such as shrimp and crab.
Are they aggressive?
Unlike other species, the fish of the Eleotridae family generally wait for the prey and remain still and near some object. Also, some of the species form schools while attacking the prey.
The fish are not dangerous to humans but they possess conical teeth and can attack if they feel threatened. Some of the species such as the bigmouth sleeper are 35.4 in (90 cm) long.
Would they make a good pet?
People generally keep species such as the empire gudgeon (Hypseleotris compressa), the peacock gudgeon (Tateurndina ocellicauda) as pets. Unlike most freshwater species, these fish can live in captivity and are easy to breed as well.
Did you know...
In several Southeast Asian regions such as Thailand, and on islands such as Sumatra, Borneo, and the Malay Peninsula, people love eating Dormitator maculates (fat sleeper) fish.
The fish of the Microphilypnus genus are so small that they resemble freshwater shrimps.
The family of Eleotridae is divided into three subfamilies namely, the Butinae, Eleotrinae, and Milyeringinae.
The planktonic larval stage of some of the species is passed in the marine water and after turning juveniles, the fish return to the freshwater. These fish are called amphidromous.
A similar family to the Eleotridaes, known as Gobiidae, consists of around 2000 species and 200 genera. These fish are also known as true gobies. The smallest vertebrates in the world such as the dwarf pygmy goby and midget dwarf goby belong to the family of Gobiidae.
The genus, Microphilypnus was discovered by G.S. Myers. Myers was one of the finest ichthyologists in the United States.
Different species of Eleotridae
The Eleotridae family consists of more than 34 genera and 180 species of fishes. The prominent species among these are the Gobiomorus dormitor also known as bigmouth sleeper, Dormitator maculatus or fat sleepers, Kimberleyeleotris hutchinsi, the empire gudgeon (Hypseleotris compressa), the peacock gudgeon (Tateurndina ocellicauda), and the Leptophilypnion fishes.
These fish are found throughout the world, many of them inhabit marine water, while others live in fresh and brackish water. The bigmouth sleeper of the West Atlantic region is around 35.4 in (90 cm) while the length of tiny-sized Leptophilypnion fish is 0.4 in (1 cm).
In countries such as New Zealand, these fish are known as bullies, while people refer to these fish as gudgeons or sleepers in Papua New Guinea and Australia.
Primarily, breeding systems such as monogamy, polygamy, and polygynandrous are followed by the species. Males of several species are involved in parental care while other fishes are not involved in parental care.
Some of them are bottom-dwellers and remain still near an object while catching the prey, whereas, some of the species form schools and hunt together. The schools or groups also help them to avoid predation.
What fish can live with Eleotridae?
People primarily keep the species of Eleotridae as pets and these fish are easy to tame and breed as well. It is suggested not to keep them with aggressive fish such as the tiger barb, nastier barb, flower horn cichlids, and many more.
These fish are carnivores but remain friendly with peaceful fishes such as the giant danios, cory catfish, zebra danios, swordtail, and platy.
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You can even occupy yourself at home by coloring in one of our free printable eleotridae coloring pages.