Dubrovnik Isopods (Armadillidium klugii 'Dubrovnik') are one of the most visually striking isopods available. Named after the historic Croatian coastal city where they originate, these "Clown Isopods" display stunning colouration that makes them an exceptional display species.
Their appearance features a dark brownish-grey body broken by three parallel rows of white spots, all bordered by vibrant red-orange "skirting" along the edges of their exoskeleton. The Dubrovnik variety is particularly prized for its higher levels of red colouration compared to other Armadillidium klugii localities - some individuals are almost entirely red, known as "Dubrovnik Red Phase."
Native to the sun-drenched Adriatic coastline, these isopods are naturally adapted to drier, well-ventilated conditions with plenty of airflow. They're not the tropical humidity lovers that many isopod species are - instead, they thrive with a strong moisture gradient, preferring predominantly dry conditions with access to a localised damp area.
While they can be slow to establish initially (losing a few in the early stages is reportedly common), once a colony gets going, Dubrovnik Isopods become hardy, prolific breeders that reward patient keepers with stunning displays.
A Glimpse
Origin: Dubrovnik, Croatia (Adriatic coast)
Scientific Name: Armadillidium klugii
Common Names: Dubrovnik Clown Isopod, Clown Isopod
Difficulty Level: Easy to Medium
Size: Up to 2cm (approximately 16-18mm)
Lifespan: 2-3 years
Temperature: 21-29°C (70-85°F)
Humidity: 50-70% (with strong moisture gradient)
Rarity: Medium
An Overview
Armadillidium klugii is distributed along the Adriatic Sea coastline, from Croatia through Montenegro, with populations also recorded in southern Albania and western Greece. The species displays significant variation in colouration and patterning depending on locality, giving rise to distinct varieties in the hobby.
The "Dubrovnik" variety specifically originates from the area around Dubrovnik, Croatia. It's distinguished from the "Montenegro" variety by its higher levels of red throughout the body and predominantly white spots (Montenegro typically shows yellow spots in the central row and less overall red colouration).
Their striking appearance isn't just for show - it's believed to be a form of mimicry camouflage. The bold red, black, and spotted pattern may help them appear dangerous to potential predators, despite being completely harmless. Their heavily calcified exoskeleton provides genuine physical protection.
Clown Isopods have become increasingly popular in the hobby due to their dramatic colouration and relative hardiness once established. They're often kept purely as display animals rather than cleanup crews, though they do perform bioactive duties effectively. Their preference for drier conditions makes them suitable for setups where high-humidity tropical species wouldn't thrive.
One thing to understand about this species: they can be notoriously slow starters. Fresh cultures often take several weeks or even months to really get going, and losing some older individuals in the initial establishment period is common. This isn't necessarily a sign that something's wrong - it's a known characteristic of the species. Patience is essential.
Varieties and Morphs
Several Armadillidium klugii varieties exist, distinguished primarily by their locality and resulting colour patterns:
Dubrovnik - Higher levels of red throughout the body with three rows of predominantly white spotting. Some individuals display such intense red colouration they're separated as "Dubrovnik Red Phase."
Montenegro - Yellow spots running down the centre of the back, with lower overall red colouration. Known for excellent colour contrast between the yellow spots and darker body.
Montenegro Orange - A selectively bred variant with orange tones.
Pudding - A darker variety with less red than either Dubrovnik or Montenegro.
If you want to maintain pure locality lines, keep different varieties separate. However, many keepers successfully mix Dubrovnik varieties with their "Dubrovnik Red" individuals to produce offspring with varying red intensity.
Basic Care
Dubrovnik Isopods require slightly different care than many isopod species - they're adapted to the sunny, breezy Adriatic coast rather than damp forest floors.
Temperature should be maintained between 21-29°C (70-85°F). Standard room temperature works perfectly. Higher temperatures within this range (around 24-29°C) may encourage more prolific breeding and help new colonies establish faster.
Humidity is where Dubrovnik Isopods differ from many species. They prefer moderate humidity of 50-70% overall, but crucially, they need a strong moisture gradient rather than uniform dampness:
- One side of the enclosure should be kept damp (wet sphagnum moss works well)
- The middle should be moderately moist
- The opposite side should be completely dry with just leaf litter coverage
This gradient allows them to self-regulate their moisture needs. They'll move between zones as required. Avoid uniformly wet conditions - excessive humidity can cause problems for this species.
Ventilation is particularly important. Native to coastal regions with constant breezes, Dubrovnik Isopods need good airflow. Ensure your enclosure has adequate ventilation holes - more than you might provide for tropical species.
Enclosure type: Glass or acrylic terrariums make excellent display enclosures and show off their colours beautifully. Plastic containers work for breeding colonies but offer less visual appeal for such a stunning species.
They're burrowers rather than climbers, so escape isn't typically a concern.
Feeding
Dubrovnik Isopods are detritivores with a particular appreciation for protein and calcium supplementation.
Primary foods (should always be available):
Hardwood leaf litter (oak, magnolia)
Decaying hardwood
Magnolia pods (a favourite)
Cork bark
Vegetable foods (offered regularly):
Sweet potato
Mushrooms
Dried peas and beans
Carrots
Dry vegetable scraps
Protein supplementation (1-2 times weekly):
Dried shrimp or shrimp pellets
Fish flakes or dried fish
Insect frass
Calcium supplementation (always available):
Cuttlebone
Crushed eggshells
Oyster shells
Important: These isopods do best with drier food offerings. Fresh, wet foods can encourage mould growth, which can be harmful. Dry vegetable scraps, dried proteins, and leaf litter are preferable to fresh, moist foods. Remove any uneaten fresh food promptly.
They may snack on soft plants and mosses, so keep them away from prized terrarium plants if this is a concern.
Colonies thrive with regular protein and calcium supplementation - this seems to significantly improve breeding success and offspring survival rates.
Appearance and Behaviour
Dubrovnik Isopods are medium-sized, reaching approximately 16-20mm (about 2cm) as adults. They have the typical Armadillidium body shape - oval, highly domed, and capable of rolling into a tight defensive ball (conglobation).
Their colouration is their defining feature:
- Dark grey-brown to black base colour
- Three parallel rows of spots running lengthwise (predominantly white in Dubrovnik, sometimes with yellow)
- Bright red-orange "skirting" along the edges of each body segment
- Some individuals display extensive red throughout the body
The intensity of red colouration varies between individuals. Particularly red specimens can be selectively bred to produce "Red Phase" cultures.
Their exoskeleton is heavily calcified, giving them substantial protection. This hard shell also makes them a calcium-rich food source for any predators that do consume them.
Sexual dimorphism: Females develop a visible white brood pouch (marsupium) between their legs as they mature. Males lack this cavity. Females also tend to be slightly larger than males.
Behaviourally, Dubrovnik Isopods are:
- Primarily burrowers (they dig into substrate rather than climb)
- Active and reasonably visible once established
- Good display animals that don't hide constantly
- Hardy once past the initial establishment phase
They can be slow to settle into new environments. Fresh cultures may take weeks or months to start breeding, with some losses of older individuals during this period. This is normal for the species - don't panic if early progress seems slow.
Habitat
Creating the right habitat is crucial for Dubrovnik Isopods, particularly the moisture gradient and ventilation.
Enclosure options:
Glass or acrylic terrariums for display
Ventilated plastic containers for breeding colonies
Shoebox-sized containers work well for colony maintenance
Temperature: 21-29°C (70-85°F). Room temperature is ideal.
Humidity: 50-70% with strong moisture gradient. Drier overall than tropical species.
Ventilation: High. Drill plenty of ventilation holes - these coastal isopods need good airflow.
Substrate depth: At least 5cm (2 inches) to allow for burrowing.
Moisture gradient setup:
- Wet zone: One side with damp New Zealand sphagnum moss
- Transition zone: Middle area kept moderately moist with leaf litter and bark coverage
- Dry zone: Opposite side completely dry, covered only with leaf litter
Hides: Provide plenty of hiding opportunities - cork bark, lotus pods, coconut halves, egg carton. Multiple hides give both juveniles and adults space and create a more enriching environment.
Enrichment: Various moss types (as both snacks and hides), bark pieces, items with different textures that break down at varying rates.
Avoid uniformly wet conditions or automated misting systems that dampen the entire enclosure. Their preference for drier conditions makes them suitable for bioactive setups that would be too dry for tropical species.
Substrate Mix
The substrate should support the moisture gradient these isopods require while providing nutrition.
Base substrate options:
Quality bioactive substrate mix
Organic topsoil and coco coir blend
Commercial isopod substrate
Essential additions:
Generous hardwood leaf litter (oak works excellently)
Decaying hardwood pieces
Cork bark flats and pieces
Sphagnum moss (for the damp zone only)
Calcium supplementation in substrate:
Crushed eggshells mixed throughout
Cuttlebone pieces scattered in enclosure
Layer structure:
- Base: 5cm+ substrate
- Top: Leaf litter layer throughout
- Damp zone: Wet sphagnum moss on one side
- Hides: Cork bark, wood pieces scattered throughout
The substrate should drain well - waterlogging must be avoided. The dry zone should remain genuinely dry, not just "less wet."
Consider adding fresh substrate and potentially new bloodlines every 6-12 months to help prevent colony crashes and maintain genetic health.
Breeding
Once established, Dubrovnik Isopods breed reliably, though getting to that point requires patience.
Establishment period: New colonies are notoriously slow to start. Expect several weeks to a few months before breeding really takes off. Losing some older individuals during this period is common and doesn't necessarily indicate problems with your care.
Breeding indicators:
- Females: White brood pouch (marsupium) visible between legs when mature
- Males: No cavity between legs
- Males tend to be slightly smaller than females
Optimal breeding conditions:
- Temperature at the higher end of their range (24-29°C)
- Strong moisture gradient maintained
- Good ventilation
- Regular protein and calcium supplementation
- Undisturbed environment
Breeding rate: Once established, they're described as "incredibly prolific." Sub-adults may begin breeding before reaching full size under good conditions.
Monitoring: Check colonies weekly as part of routine maintenance. Look for mancae (babies), gravid females, and any issues that need addressing.
Colony health tips:
- Avoid harsh chemicals and candle smoke near enclosures (can cause crashes)
- Add new bloodlines periodically (every 6-12 months) to maintain genetic diversity
- Refresh substrate occasionally
- Maintain consistent conditions - stability matters
With proper care and patience through the establishment phase, Dubrovnik Isopods reward keepers with beautiful, active colonies that showcase some of the most striking colouration in the isopod hobby.
