Fun Ryukyu Spiny Rat Facts For Kids

Arpitha Rajendra
Oct 20, 2022 By Arpitha Rajendra
Originally Published on Aug 06, 2021
Edited by Luca Demetriou
Fact-checked by Pradhanya Rao
Interesting Ryukyu spiny rat facts to read on at Kidadl

Ryukyu spiny rat (Tokudaia osmensis) is a rodent species of the Muridae family and order Rodentia. These rats are endemic to Amami Oshima island of the Amami islands of the archipelago of Japan.

This family is the largest rodent family and also of mammals. There are more than 700 species spread across Africa, Australia, and Eurasia, which include rats, mice, and gerbil species.

Muridae is a derivative of the Latin word 'mus', which translates to 'mouse.' There is only a little evidence of Ryukyu spiny rat found, so, the evolution of murids is not well known.

There's a possibility that this species evolved from hamster-like species sometime around the early Miocene in tropical Asia. The Ryukyu spiny rat is of the subfamily Murinae, which contains old-world mice and rats. There are four other subfamilies of this family.

The species of this family have a great sense of smell and hearing. The fossil record of the Murinae subfamily shows that they first appeared around 14 million years ago in the Antemus genus.

The Murinae subfamily contains 129 genera and 584 species as of 2005. The Ryuku spiny rat is threatened and at the risk of extinction in the wild.

If you like these facts about Ryukyu spiny rats, then do read these mongoose facts and black rat facts for more.

Ryukyu Spiny Rat Interesting Facts

What type of animal is a Ryukyu spiny rat?

Ryukyu spiny rat (Tokudaia osimensis) is a species of spiny rat of the order Rodentia, family Muridae, and genus Tokudaia. The Ryukyu spiny rat's SRY gene and the Ryukyu spiny rat's Y chromosomes are lost.

This species of rat has XO/XO sex chromosomes. These genes are usually expressed in Ryukyu spiny rat gonads and the brains of both sexes. It is considered that T. tokunoshimensi and T. osimensis diverged from the Tokudaia muenninki species.

What class of animal does a Ryukyu spiny rat belong to?

Ryukyu spiny rat (Tokudaia osimensis) is of the class Mammal and genus Tokudai.

How many Ryukyu spiny rats are there in the world?

The data on the population of Ryukyu spiny rat is not available. However, the population is considered to be in the billions.

Where does a Ryukyu spiny rat live?

The species of genus Tokudaia are spread across the non-contiguous island. Tokudaia osimensis is an endemic species to the Amami Oshima island in the Amami islands, which is a part of Ryukyu archipelago of Japan.

What is a Ryukyu spiny rat's habitat?

The natural habitat of Tokudaia osimensis is a subtropical moist broadleaf forest. There is only a little information on the ecology and habitat range of this species.

However, the species of the order Rodentia are found in the natural terrestrial habitat range even in human-made surroundings. Also, they inhabit less than 3 km area. Rodents are found around urban area and agricultural area.

Who do Ryukyu spiny rats live with?

There is little information known on Ryukyu spiny rat natural habitat. So, usually, Rodentia species live underground in groups and develop a burrow system.

How long does a Ryukyu spiny rat live?

Tokudaia osimensis lifespan data is not available. However, the average lifespan of a spiny rat is  2-4 years.

How do they reproduce?

Ryukyu spiny rat is nocturnal so they nest, sleep, and store food in rock crevices, burrows of other animals, and hollows in logs or trees. Even though they lack sex chromosomes, males are able to produce sperm. This suggests that males have newly acquired genes.

All Ryukyu spiny rat female gain sexual maturity at an early age. There is no information on the sex chromosome, sexual maturity or sexual dimorphism found that impacts reproduction. Of the spiny rat species, a large number of males breed every season.

What is their conservation status?

The conservation status of Ryukyu spiny rat is Endangered and are at risk of extinction in the wild. This species face threats by predators, habitat destruction and fragmentation by human beings.

Ryukyu Spiny Rat Fun Facts

What do Ryukyu spiny rats look like?


*Please note that this is an image of a rodent, not a Ryukyu spiny rat specifically. If you have an image of a Ryukyu spiny rat please let us know at

There is very little information on the description of this species. However, spiny rats of the family Muridae have a rat-like pointed nose with a brown to gray body.

Their front foot has four toes and the hindfoot has five toes. They have noticeable bristly and spiny fur mostly on their rumps and backs. They have creamy or white underbellies.

How cute are they?

These small rodents are not considered cute.

How do they communicate?

Like all other rats in the family Muridae, these spiny rats communicate using their senses like touch, smell, and hearing. They communicate with each other using pheromones.

How big is a Ryukyu spiny rat?

The exact size of these rats is unavailable. Ryukyu spiny rats are smaller rodents of the other two in this genus. Spiny rats can be 4-19 in (10-48 cm) long.

How fast can a Ryukyu spiny rat run?

The data on the speed of Ryukyu spiny rat is unavailable.

How much does a Ryukyu spiny rat weigh?

The average weight of Ryukyu spiny rat is around 0.18 lb (85 g).

What are the male and female names of the species?

Female Ryukyu spiny rats are called does and males are called bucks.

What would you call a baby Ryukyu spiny rat Rat?

There is no specific name given to a baby Ryukyu spiny rat. They are often referred to as pinkie, pup, kitten, or nestling.

What do they eat?

These rats mostly feed on seeds, small insects, and worms. The depend highly on plants and fruits.

Are they dangerous?

This species is not dangerous to human beings.

Would they make a good pet?

No, they would not make a good pet. They do well in moist regions in forests.

Did you know...

All three species of genus Tokudaia are threatened or endangered and are at risk of extinction.

Okinawa spiny rat (Tokudaia muenninki) have thick and short body with dense fur. They are found in the northern area of Okinawa island.

These rats of genus Tokudaia face predators like feral cats and dogs and introduced mongooses. They face competition from the introduced black rats.

Of the three species in genus Tokudaia of the order Rodentia, T. tokunoshima and T. osimensis, two species have lost sex chromosomes, whereas Tokudaia muenninki have abnormally large sex chromosome.

The sex chromosomes of T. tokunoshima and T. osimensis is XO/XO and T. muenninki has XX/XY sex chromosome

Many species of Rodentia order have been used for food, clothes, as lab animals, and as pets.

The species of Rodentia cause huge damage to crops and also carries disease.

A group of Ryukyu spiny rat is called plack, plague, swarm, or colony.

The Arboreal spiny rats break off their tail when they are attacked by predators. The tails grow back.

Even though the Arboreal spiny rats resemble rats, they are close relatives of guinea pigs and chinchillas.

American spiny rat is medium-sized rodents of Central and South America. They are slender with long whiskers and have short limbs.

Rodents have strong lower and upper pairs of teeth that grow continuously.

Rats are highly intelligent and are empathetic creatures. They also make lifelong relationship with their owners.

Many rats develop medical problems so they are short-lived.

The Ryukyu long-tailed giant rat is the only extant rodent species in the Diplothrix genus. They are threatened by habitat loss.

Why are they called Ryukyu spiny rats?

The Ryukyu spiny rats are found in Ryukyu Islands. They are named spiny rats due to their bristly, spiny looking fur on their back and rump.

Are Ryukyu spiny rats endangered?

The conservation status of Ryukyu spiny rats is Endangered. The other species of spiny rats are threatened, endangered, or extinct. These rats are facing the risk of extinction in the wild. Spiny rats can be found in many restricted and protected areas.

Here at Kidadl, we have carefully created lots of interesting family-friendly animal facts for everyone to discover! Learn more about some other mammals including nutria, or water rat facts.

You can even occupy yourself at home by drawing one on our Ryukyu Spiny Rat coloring pages.

* Please note that this is an image of a rat, not a Ryukyu spiny rat specifically. If you have an image of a Ryukyu spiny rat please let us know at

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Written by Arpitha Rajendra

Bachelor of Engineering specializing in Aeronautical/Aerospace Technology, Master of Business Administration specializing in Management

Arpitha Rajendra picture

Arpitha RajendraBachelor of Engineering specializing in Aeronautical/Aerospace Technology, Master of Business Administration specializing in Management

With a background in Aeronautical Engineering and practical experience in various technical areas, Arpitha is a valuable member of the Kidadl content writing team. She did her Bachelor's degree in Engineering, specializing in Aeronautical Engineering, at Nitte Meenakshi Institute of Technology in 2020. Arpitha has honed her skills through her work with leading companies in Bangalore, where she contributed to several noteworthy projects, including the development of high-performance aircraft using morphing technology and the analysis of crack propagation using Abaqus XFEM.

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Fact-checked by Pradhanya Rao

Bachelor of Commerce specializing in Marketing and HR

Pradhanya Rao picture

Pradhanya RaoBachelor of Commerce specializing in Marketing and HR

With a Bachelor’s degree in Commerce from Christ University, Bangalore, Pradhanya's passion for the English language and literature led her to explore the field of content writing, where she has gained extensive experience in writing, reviewing, editing, and fact-checking. She has also earned certifications in Google Ads Search, Google Ads Display, and Social Media Marketing, showcasing her proficiency in digital marketing.

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