Fun Rubyfish Facts For Kids

Christian Mba
Oct 20, 2022 By Christian Mba
Originally Published on Sep 02, 2021
Edited by Jacob Fitzbright
Fact-checked by Kidadl Team
Amazing ruby fish facts that kids will love.
Age: 3-18
Read time: 6.1 Min

Plagiogeneion rubiginosum, also called rubyfish, inhabits the southern and eastern Atlantic Ocean around South Africa to the Indian Ocean and as far as the west Pacific Ocean covering Western Australia and New Zealand on the map. This species belongs to the family Emmelichthyidae, and they are also known as long-tail snappers. Plagiogeneion rubiginosum looks similar to flame snappers, only they do not have a forked caudal fin. The rubyfish (Plagiogeneion rubiginosum) is an elongated fish and looks beautiful because of its skin color, which is red and pinkish white. The dorsal and fins are red and the lower lobe of the fin is white. This genus species of rubyfish (Plagiogeneion rubiginosum) inhabits continental shelf and slope waters.

Their habitat distribution can be observed across tropical waters of the Indo-west and Central Pacific, making them quite cosmopolitan rubyfish. These marine species in the Australian map inhabit northern Queensland. These Atlantic rubyfish eat other fishes, squid, and crustaceans. This species is fished commercially. This fish is a known delicacy along the coastal regions of countries like Australia and New Zealand, and other parts of the world. As per the IUCN, this species is of Least Concern due to its stable population. Today, overfishing is one of the concerns for the population of these fish species.

If you wish to know more about other fish species, feel free to check out blackfin dartfish facts and Irish lord fish facts.

Rubyfish Interesting Facts

What type of animal is a rubyfish?

Rubyfish, Plagiogeneion rubiginosum, are also known as cosmopolitan rubyfish, and are being overfished throughout draw fisheries across its distribution in South Africa, Australia, and New Zealand. They are beautiful to look at.

What class of animal does a rubyfish belong to?

Rubyfish, Plagiogeneion rubiginosum, is a fish species that belongs to the class of Actinopterygii. The classification of this species of fish is not extensive.

How many rubyfish are there in the world?

The total number of rubyfish present across the world is unknown. However, it is known that their population is stable for now.

Where does a rubyfish live?

These marine Hutton fish's habitats can be observed in South Africa, Western Australia, and New Zealand. The Australian Hutton has been caught through trawl fisheries. These marine species inhabit northwestern Australia, Western Australia, northeastern Queensland, and sometimes further south.

What is a rubyfish habitat?

Rubyfish, Plagiogeneion rubiginosum, inhabit the southern and eastern Atlantic Ocean to the Indian Ocean and as far as the western Pacific Ocean. This fish prefers to live at depths of around 164-1640.42 ft (50-500 m) underwater. They live among rocks to safeguard themselves from other big fishes and occasionally come out to feed on crustaceans and seaweeds.

Who does rubyfish live with?

Cosmopolitan rubyfish live in packs or groups, known as schools.

How long does a rubyfish live?

Cosmopolitan rubyfish have a total lifespan of around 90 years or more. They are long-lived sea creatures that grow slowly and feed on larger zooplankton. These fish are caught throughout the year by trawl fisheries in Australia and New Zealand coastal regions.

How do they reproduce?

Little is known about cosmopolitan rubyfish reproduction, spawning, and mating behavior. They swim across the ocean in search of food and packs in the depths of ocean water and are caught through trawl fisheries many times. Females can lay around 250-1000 eggs per season.

What is their conservation status?

As per the IUCN Red List, this species and all its classifications are of Least Concern across its distribution range in Australian waters, New Zealand, and South Africa. They have been used for commercial purposes through trawl fisheries, yet their population is of Least Concern.

Rubyfish  Fun Facts

What does the rubyfish look like?

Rubyfish have a red to bright pinkish body coloration.

*Please note that this is an image of a red mullet that closely resembles the rubyfish. If you have an image of a rubyfish, please let us know at

Cosmopolitan rubyfish look similar to flame snappers, only that they do not have a forked caudal fin. Cosmopolitan rubyfish are elongated in shape and look beautiful because of the pinkish and red skin coloration that they have. Their dorsal fins are red, while their lower lobe fin is white. The length of this fish species ranges between 7.8-11.8 in (20-30 cm) and weighs around 1.7-3.9 lb (0.8-1.8 kg). This marine creature's distribution can be found across the ocean from the Atlantic to the Pacific and Indian Oceans. Their presence has also been observed in freshwater. They can swim in great depths across a great range of the sea due to the well-balanced length of their body.

How cute are they?

Cosmopolitan rubyfish are very cute to look at. They swim across a range of oceans in search of food at great depths in the ocean water. They are elongated fish and look beautiful because of their skin color, which is red and pinkish white. The total length of this fish is quite great and similar to Indian mackerel.

How do they communicate?

Cosmopolitan rubyfish communicate with each other through signals and signs. However, the exact means of their communication, or the sound they use to communicate, is unidentified.

How big is a rubyfish?

The total body length of this fish is around 7.8-11.8 in (20-30 cm), which is five times smaller than northern searobin.

How fast can a rubyfish swim?

Cosmopolitan rubyfish are fast swimmers, as they have been observed to swim across their distribution from New Zealand waters to Australian waters in search of their pack or partners and are found at depths of 164-1640.42 ft (50-500 m) in the ocean. They are caught by trawl fisheries.

How much does a rubyfish weigh?

The range of their weight can be around 1.7-3.9 lb (0.8-1.8 kg), which is 10 times smaller and lighter than chum salmon.

What are the male and female names of the species?

There are no specific names used to describe the male and female of this fish.

What would you call a baby Rubyfish?

Baby rubyfish are called fry, and when they are young, they can be found at a maximum depth range of 164 ft (50 m) in the ocean.

What do they eat?

They travel in search of food across New Zealand and Australian waters and feed on small fish, squid,  and crustaceans like shrimp, krill, lobster, and crabs. However, they have been used for commercial purposes through overfishing via trawl fisheries.

Are they dangerous?

No, they are not dangerous to humans and have been used for commercial purposes through trawl fisheries. They also have a stable population as they have been listed as Least Concern on the IUCN Red List.

Would they make a good pet?

They need a depth of at least 164 ft (50 m) to be kept as pets, so it may be impractical.

Did you know...

Rubyfish are among the most highly targeted and searched for commercial fish in New Zealand, as they are a great delicacy.

What is the other name of Rubyfish?

Rubyfish are also known as cosmopolitan rubyfish because of their cosmopolitan habitat. They are also known as Hutton fish and rock salmon.

Is Rubyfish good to eat?

Yes, they are good to eat. Overfishing through trawl fisheries has been used to catch them around Australian waters and New Zealand. One of the favorite seafood of people across the world is rubyfish. Cooking them does not require special skills since one can steam them, make soup, fry them or even serve them as sushi. It is quite a famous delicacy along with the coastal areas including Australia, New Zealand, and South Africa. They are among the most sought-after fish in the world.

Here at Kidadl, we have carefully created lots of interesting family-friendly animal facts for everyone to discover! Learn more about some other fishes from our dusky damselfish facts and driftfish facts pages.

You can even occupy yourself at home by coloring in one of our free printable rubyfish coloring pages.

Rubyfish Facts

What Did They Prey On?

Crustaceans and seaweed

What Type of Animal were they?


Average Litter Size?

250-1000 eggs

How Much Did They Weigh?

1.7-3.9 lb (0.8-1.8 kg)

What habitat Do they Live In?

ocean and freshwater

Where Do They Live?

indian ocean, pacific ocean

How Long Were They?

7.8-11.8 in (20-30 cm)

How Tall Were They?








Scientific Name

Plagiogeneion rubiginosum

What Do They Look Like?

Red, pink, white

Skin Type

Wet and slimy scales

What Are Their Main Threats?

overfishing and water pollution

What is their Conservation Status?

Least Concern
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Written by Christian Mba

Bachelor of Science specializing in Computer Science

Christian Mba picture

Christian MbaBachelor of Science specializing in Computer Science

Christian Mba is an experienced blogger and content writer with over a decade of experience. He holds a Bachelor of Science degree in Computer Science from Nigeria and has a keen interest in Python programming. Along with his writing and blogging expertise, he is also an SEO specialist with more than six years of experience. Chris, as he is commonly known, has a passion for music and enjoys playing the piano.

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