Giant Cannonball Isopods (Helleria brevicornis)

The Giant Cannonball Isopods are one of the largest and rarest species that can roll up into a ball. Due to its large appearance and characteristics, it is sought by hobbyists and exotic pet owners. This large terrestrial rolling critter is the only species that are closely related to marine isopods.

A Glimpse

●      Origin: Corsica and Sardinia

●      Scientific Name: Helleria brevicornis

●      Ventilation: Medium

●      Difficulty in Breeding: High

●      Average Size: 3 cm

●      Rarity: high

●      Temperature: 64℉-79℉

●      Humidity: Medium to high

Giant Cannonball Isopods are one of the rarest species of roly polys that bear a close kinship with marine isopods in oceans and seas. These species are endemic to the Corsica and Sardinian regions and are not found in mainland areas. These remarkable species are one of nature's wonders and are quite a captivating addition to your terrariums.

Giant Cannonball Isopods: Physical Features, Characteristics and Traits

●      It is a unique isopod and one of the largest isopod species that can conglubulate.

●      These species are related to the Terranean Sea isopods and are found only in Corsica, Croatia, and Sardinia.

●      They have a mild sand color to their exoskeleton, with their rear end curled inwards.

●      These species have a bulky appearance and are shy creatures that rarely appear on the surface. They are very light-sensitive and prefer darkness over well-lit space.

●      These species are active during night time, i.e., they are nocturnal in nature.

●      These species require a specific substrate mix, which is rich in organic material and detritus.

●      They primarily feed on rotten leaves and wood, very little vegetable and fruit scraps but consume very little to no calcium supplements.

●      These species are not ideal cleanup crews as they are picky in terms of diet.

●      Some breeders also say that they're the isopod version of millipedes, which makes them different from other isopod species.

●      I prefer a humid climate and moderate temperature. They're not a huge fan of dry substrate, so humidity and moisture need to be controlled.

●      These critters like warm temperatures around 74℉ to 78℉ during the spring season. Therefore, the temperature needs to be maintained for optimal health.

●      During the fall and winter seasons, these creatures must be put in a winter diapause for three months. This aids in the overall breeding process and the overall health of the species.

●      These species are prolific in nature, but they are slow-growing species. The babies, once born, will reach sexual maturity after 8 to 12 months.

Dietary Requirements

They mostly prefer plants that are decayed and rotting parts of wood.  These species keep a very balanced diet and do not prefer food that is supplied from outside. They love food that is naturally decayed and present inside the substrate.

When you provide a food substitute like isopod superfood, mix it with substrate and it has to be ensured that you are providing the necessary amount of protein such as fish and meat scraps. You can also provide little vegetable scraps but make sure to provide a little amount.

These species don't have a very voracious appetite. Make sure to avoid any mold on the food as it may not consume it.

Giant Cannonball Isopods: Reproduction and Breeding Process

There is a belief that these species will reproduce only once in a lifetime. However, providing a mild winter diapause promotes the female isopods to breed every year and not once a lifetime. This is because in their natural habitat, winters are relatively cold, and they halt their breeding. So, by providing this brief winter diapause, you will be able to make them breed for multiple years and also help you achieve a sizable colony.

Therefore during the spring season the temperature should be maintained between 74 - 78 degree fahrenheit for a good breeding rate and to produce healthy babies. In the winter season the temperature inside the enclosure is to decrease to at least 60 degrees fahrenheit.

During the breeding months, the male isopod takes a position above the female isopods, which is also called a nuptial ride, for a period of one month. It is done to ensure that this is the only father of the brood. Post fertilization, the female counterparts burrow holes in multiple locations and ensure that food sources are available around the holes. They do this to ensure that their broods receive nutrition after birth.

During birth an egg-like mancae is formed between the legs of the female isopods. The brood will come out of this only after the first successful molting in a few hours. Once they are born, then the female isopod will continue to assist their broods. After a few weeks these broods will grow enough to find their own food independently.

The initial size when they are born is approximately two centimeters, and they reach sexual maturity in about eight to twelve months.

Substrate Mixture

●      It is to be ensured that the enclosure is filled with high substrate filling and that the substrate has a proper composition of organic matter like decayed materials of plants or wood.

●      The mixes should consist of forest humus, leaves that are rotten, and rotten parts of white wood in an equal ratio.

●      Make sure that the substrate mix has a minimum thickness of 15 cm.

●      The top layer of the mix can be covered using leaves, and rotten tree bark can be placed for them to hide. This ensures that you are providing an ecosystem similar to their natural habitat.

●      The amount of humidity inside the substrate should be controlled. It should not happen that the mix is very moist, and it is also important to check that the temperature inside the enclosure is controlled.

●      Proper ventilation is provided by drilling holes in the enclosure. This prevents excess humidity in the terrarium.

●      You have to keep the enclosure in a dark area as they are sensitive to light, and they don't prefer areas with high intensity of light.

If you can follow the above mentioned methods , you can easily keep the culture in optimal health conditions and also help them breed healthy broods.