Giant Mandarin Isopods (Cubaris)

Cubaris sp. "Giant Mandarin" is a larger Thai Cubaris species with bright orange colouration and distinctive red eyes. The name is apt—they're approximately three times larger than the common Cubaris murina "Mandarin" morph, reaching around 17mm as adults. They're believed to be related to Cubaris sp. "Giant Marina," sharing similar size characteristics but with their own orange pigmentation. For keepers wanting the appealing Cubaris "duck face" look in a more substantial package, Giant Mandarins deliver.

A Glimpse

• Origin: Thailand (captive-bred)
• Scientific Name: Cubaris sp. "Giant Mandarin"
• Common Names: Giant Mandarin Isopod
• Maintenance required: Medium
• Average Size: Up to 17mm
• Rarity: Uncommon
• Temperature: 22-28°C (72-82°F)
• Ventilation: Low to Medium
• Humidity: 60-80%
• Favorite food: Leaf litter, fruits, vegetables, decaying wood
• Supplements: Protein (twice weekly), calcium

Giant Mandarin Isopod: Introduction

Cubaris species have taken the isopod hobby by storm over the past few years, particularly since the discovery of the famous Rubber Ducky isopod in Thai limestone caves in 2017. Giant Mandarins are part of this wave of Southeast Asian Cubaris that combine interesting appearance with the characteristic rounded "duck face" that makes the genus so appealing.

The "Giant" in the name refers to their size relative to smaller Cubaris morphs—at 17mm, they're substantial for the genus but not truly giant compared to species like Porcellio magnificus. They're roughly three times larger than the common Cubaris murina "Mandarin," which makes them easier to observe and gives them more visual presence in an enclosure.

Their origin appears to be Thailand, possibly isolated from Cubaris sp. "Giant Marina." Like most Cubaris, they appreciate higher humidity, deep substrate for burrowing, and a protein-supplemented diet. They're not the most demanding Cubaris species, but they're not as forgiving as beginner isopods either—moderate care is required.

Giant Mandarin Isopod: Physical Traits and Characteristics

• Adults reach approximately 17mm in length
• Bright tangerine-orange body colouration
• Distinctive red eyes (a striking feature)
• Characteristic Cubaris "duck face" with rounded head
• Chunky, robust body shape
• Can roll into a ball (conglobation) when threatened
• Colour may intensify with age and proper nutrition

The red eyes are particularly notable—they contrast attractively against the orange body and make identification straightforward. The orange colouration ranges from lighter tangerine to deeper orange depending on individual, age, and diet.

Behaviour

Giant Mandarins display typical Cubaris behaviour patterns.

Activity patterns: Active throughout day and night, but most visible during evening and nighttime hours. Like most Cubaris, they're often described as "shy" but become bolder as colony numbers increase.

Burrowing: Semi-fossorial—they spend considerable time burrowed into substrate but also forage through leaf litter and under bark. Provide adequate substrate depth (10-15cm) to accommodate this behaviour.

Conglobation: They can roll into balls when threatened, typical of many isopod species.

Social behaviour: Gregarious. They aggregate in favoured hiding spots under cork bark and in substrate pockets. Higher numbers lead to more visible activity.

Climbing: Capable climbers. Some Cubaris species can climb smooth vertical surfaces, so secure lids with fine mesh are sensible.

Response to disturbance: Either conglobate or exhibit rapid escape responses, quickly scuttling to safety.

Diet

Giant Mandarins have dietary needs typical of Cubaris species, with particular emphasis on protein.

Primary foods:

• Hardwood leaf litter (oak, beech, birch, maple)
• Decaying white-rotted wood
• Forest moss and lichens

Supplementary foods:

• Sweet fruits (apples, oranges, mango—particularly enjoyed)
• Vegetables: sweet potato, carrot, squash, courgette
• Commercial isopod foods

Protein: Cubaris species have higher protein requirements than many isopods. Offer protein sources twice weekly:

• Fish flakes or pellets
• Freeze-dried shrimp or minnows
• Dried bloodworms
• Reptile shed skin

Adequate protein helps prevent cannibalism and supports healthy breeding.

Calcium: Provide cuttlebone, crushed limestone, or oyster shell. Limestone is particularly appropriate given that many Cubaris originate from limestone cave environments.

Feeding approach: Leaf litter should form the base of their diet—keep it available at all times. Supplement with vegetables, fruits, and protein. Remove uneaten fresh foods before they mould. They seem particularly fond of sweeter foods.

Giant Mandarin Isopod: Breeding

Giant Mandarins breed at a fair rate once established, though not as prolifically as some species.

Breeding basics:

• Reproduction rate: Fair (not fast, not slow)
• Growth rate: Normal to slow
• Females carry eggs in brood pouch
• Stable conditions encourage breeding

Establishment period: Like many Cubaris, they may take time to establish and begin breeding at a meaningful rate. Patience is required—don't expect rapid population growth initially.

Tips for breeding success:

• Maintain stable temperature (22-28°C)
• Keep humidity consistent (60-80%)
• Provide adequate protein
• Minimise disturbance
• Ensure deep substrate for burrowing
• Provide ample hiding spots

Brood size: Moderate brood sizes typical of Cubaris species. Population growth is steady rather than explosive once the colony establishes.

Giant Mandarin Isopod: Habitat Setup

Cubaris require more attention to setup than beginner species.

Enclosure: A 6-quart container works for starter colonies, but larger setups (12+ quart) better accommodate their burrowing behaviour and allow the colony to establish. Plastic storage containers with modified ventilation are standard. Secure lids are necessary as they can climb.

Ventilation: Low to medium. Cubaris need good airflow despite requiring high humidity—stagnant air can be problematic. Cross ventilation (holes on opposite sides) works well. Cover ventilation holes with fine mesh to prevent escapes and keep out pests.

Substrate: Deep substrate is important for Cubaris—aim for 10-15cm (4-6 inches) minimum:

• Organic topsoil as base (pesticide-free)
• Forest humus mixed in
• Sphagnum peat moss for moisture retention
• Decaying white-rotted wood pieces (substantial proportion—15%+)
• Crushed limestone mixed throughout (10%)
• Leaf litter layered on top

The limestone is particularly relevant as many Cubaris originate from limestone environments. It provides calcium and may help replicate natural conditions.

Humidity: 60-80%—consistently moist but not waterlogged:

• Keep approximately one-third of enclosure consistently moist with sphagnum moss
• Mist the moist section 2-3 times weekly
• Allow remaining area to be moderately humid but not wet
• Substrate should feel like a wrung-out sponge in moist areas
• Monitor carefully—Cubaris are sensitive to both desiccation and overly wet conditions

Temperature: 22-28°C (72-82°F). Consistent warmth is more important than hitting exact numbers. Avoid temperature swings, particularly during moulting periods. Room temperature in heated UK homes generally works, but cooler rooms may need supplemental heating in winter.

Décor:

• Cork bark pieces (they love hiding underneath)
• Leaf litter (essential—forms bulk of diet)
• Decaying wood pieces
• Sphagnum moss patches in moist areas

Bioactive Use

Giant Mandarins can work in bioactive setups but require consideration.

Suitable applications:

• Tropical bioactive vivariums with high humidity
• Dart frog enclosures (though they may be too large for smaller frogs to eat)
• Display terrariums
• Humid reptile setups

Strengths:

• Attractive orange colouration
• Visible size
• Effective decomposers
• Interesting behaviour

Considerations:

• Require higher humidity than many bioactive setups provide
• Need deep substrate for burrowing
• Moderate care requirements mean less tolerance for suboptimal conditions
• Not as prolific as Porcellio or Armadillidium—may not sustain population under heavy predation
• Higher protein needs—may struggle if only organic waste is available

Best approach: If using in bioactive setups, establish the colony separately first, then introduce once numbers are sufficient. Supplement their diet even in bioactive systems to maintain the colony.

Tank Mates

Compatible with appropriate invertebrates and vivarium inhabitants.

Compatible:

• Other isopod species (though keeping Cubaris separately prevents potential hybridisation issues)
• Springtails (beneficial—they complement each other)
• Small snails

As cleanup crew for:

• Dart frogs (smaller frogs won't eat adults; larger frogs may)
• Day geckos
• Small skinks
• Other humid-environment reptiles and amphibians

Note: Their moderate breeding rate means heavy predation may deplete the population. They work better as cleanup crews than as feeders.

Suitability

Giant Mandarins suit keepers with some isopod experience who want attractive Cubaris.

Good choice for:

• Intermediate keepers stepping up from beginner species
• Those wanting Cubaris with more visual presence than smaller species
• Keepers who appreciate the orange/red-eye colour combination
• Display colony enthusiasts
• Humid bioactive setup cleanup crews

Less suited for:

• Complete beginners (start with something more forgiving)
• Arid or low-humidity setups
• Those wanting fast-breeding feeder colonies
• Keepers who prefer hands-off, low-maintenance species

Care level: Moderate. Easier than some demanding Cubaris species, but not as forgiving as Porcellio or Armadillidium. Requires attention to humidity, temperature stability, and protein supplementation. Success depends on providing consistent conditions and understanding their needs.

Value: At £30 for 5 (with bulk pricing available), they're reasonably priced for a Cubaris species. Not cheap, but not premium Rubber Ducky pricing either. The combination of larger size, attractive colouration, and red eyes makes them visually interesting without requiring exotic-species budgets.

What to expect: Expect attractive orange isopods with distinctive red eyes that spend considerable time burrowed or hidden but emerge to forage, particularly in evening hours. Expect moderate breeding once established—not explosive population growth, but steady increases over time. Expect to provide more consistent care than beginner species require. Their larger size compared to smaller Cubaris morphs makes them more satisfying to observe, and the colour combination is genuinely appealing. They reward keepers who provide appropriate conditions without being unreasonably demanding. For those interested in Cubaris but not ready for the most challenging species, Giant Mandarins represent a sensible middle ground.