Trachelipus caucasius is a hardy isopod species originating from the Caucasus region, found around the Black Sea coasts of Russia, Georgia, and Turkey. Sometimes called "Trilobite isopods" due to their body shape, they display attractive grey colouration often accented with orange edging along the segments. At 2-4 cm when fully grown, they're a substantial species that's easy to observe, and their tolerance for a range of temperatures combined with straightforward care makes them a practical choice for keepers at all experience levels.
A Glimpse
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Origin: Caucasus region (Russia, Georgia, Turkey - Black Sea coastal areas)
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Scientific Name: Trachelipus caucasius
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Maintenance required: Low
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Average Size: 2-4 cm
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Rarity: Medium
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Lifespan: 2-3 years
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Temperature: 18-26°C (64-79°F)
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Ventilation: Medium to High
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Humidity: 60-75% (with moisture gradient)
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Favorite food: Leaf litter, decaying hardwood, vegetables
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Supplements: Cuttlefish bone, crushed limestone, eggshells
Trachelipus caucasius: Introduction
Trachelipus caucasius comes from the subtropical climate zones around the Black Sea, where conditions include warm summers, mild autumns, and cold winters. This natural environment has made them adaptable to a broader temperature range than many tropical isopod species—they'll handle cooler conditions that would stress more sensitive species, while also thriving in warmer setups.
Their common nickname "Trilobite isopods" comes from their body shape, which has a segmented, somewhat flattened appearance reminiscent of the ancient trilobite fossils. Combined with their grey colouration and orange-edged segments, they have a distinctive look that sets them apart from more commonly kept species.
They're considered beginner-friendly due to their tolerance for varying conditions and willingness to breed in captivity. For keepers wanting something slightly different from the standard Porcellio or Armadillidium species without demanding care requirements, Trachelipus caucasius are worth considering.
Trachelipus caucasius: Physical Traits and Characteristics
- Large species, with adults reaching 2-4 cm in length
- Grey base colouration across the body
- Orange or amber-coloured edging along segment margins in many individuals
- Somewhat flattened body profile compared to rounder Armadillidium species
- Segmented appearance contributing to the "trilobite" nickname
- Hard exoskeleton providing protection
- Cannot fully conglobate (roll into a complete ball) like Armadillidium—they rely on speed and finding cover
- Prominent antennae and visible uropods
Behaviour
Trachelipus caucasius are active, adaptable isopods with a peaceful temperament.
Activity levels: Once established, they're reasonably active and visible. Their larger size makes them easy to spot when foraging, and they don't hide as constantly as some more secretive species.
Temperament: Peaceful and non-aggressive. They coexist well with other isopod species and terrarium inhabitants. They're not predatory and won't cause problems in mixed setups.
Temperature tolerance: Their subtropical origins mean they handle temperature variation better than tropical species. They can tolerate cooler conditions (down to around 15°C for short periods) without significant stress, though they thrive best in the 18-26°C range. This makes them suitable for unheated enclosures in many UK homes.
Defence: They can't roll into a complete ball like Armadillidium species. When threatened, they rely on moving quickly to find cover.
Settling in: Generally adaptable and settle into new enclosures without extended adjustment periods.
Diet
Trachelipus caucasius are detritivores with undemanding dietary requirements.
Primary foods:
- Dried leaf litter (oak, beech, hawthorn, and similar hardwoods)
- Decaying hardwood
- Cork bark
- Wood pieces
Supplementary foods:
- Vegetables: carrot, courgette, sweet potato, cucumber
- Dried vegetable scraps work well
- Fish flakes for protein
- Small amounts of fruit occasionally
Calcium: Important for healthy moulting, especially given their larger size. Provide cuttlefish bone, crushed limestone, or eggshells as a constant calcium source.
Feeding approach: They're not fussy eaters. Maintain a base of leaf litter and decaying wood, supplementing with vegetables every few days. Remove uneaten fresh foods within 24-48 hours. Their size means they have reasonable appetites, but don't overfeed—let them work through what's provided before adding more.
Trachelipus caucasius: Breeding
This species breeds well in captivity, with a reputation for reliable reproduction under appropriate conditions.
Breeding basics:
- Females carry eggs in a marsupium and release fully formed juveniles
- Breeding rate is good—they're considered fast breeders
- Brood sizes are reasonable given their larger adult size
- Population growth is steady under proper conditions
Conditions for breeding:
- Stable temperature within preferred range (18-26°C)
- Appropriate humidity with moisture available
- Adequate calcium for breeding females
- Sufficient hiding spots
- Consistent food availability
Colony growth: Expect reliable population growth without the frustrating waits associated with slow-breeding species. They're productive breeders that will build colony numbers consistently.
Trachelipus caucasius: Habitat Setup
Enclosure: A medium to large container suits this species well given their size. A 15-20 litre container works for a starter colony, with larger enclosures beneficial as populations grow. Good ventilation is important—their subtropical origins mean they appreciate airflow.
Substrate: Use a moisture-retentive substrate that can maintain a humidity gradient:
- Organic topsoil as a base (pesticide-free)
- Sphagnum peat moss mixed in for moisture retention
- Leaf litter worked into the substrate and layered generously on top
- Decaying hardwood pieces
- Crushed limestone or calcium powder throughout
Substrate depth of 5-10 cm allows for some burrowing and helps maintain stable moisture levels at lower depths.
Moisture gradient: They prefer humid conditions but benefit from having both moist and drier areas available. Set up approximately half the enclosure with damp substrate and sphagnum moss, allowing the other half to stay somewhat drier. This lets them regulate their moisture needs.
Overall humidity: Aim for 60-75%. They need access to moisture but aren't as humidity-dependent as tropical cave-dwelling species. Regular misting of the humid side maintains appropriate conditions.
Ventilation: Medium to high ventilation suits this species. Their subtropical climate origins mean they're accustomed to airflow. Use mesh lids or plenty of ventilation holes. Stagnant, overly humid conditions aren't ideal for them.
Décor and hides:
- Cork bark pieces and tubes
- Flat bark and wood pieces
- Leaf litter coverage (they appreciate generous amounts)
- Hardwood branches
- Stones or slate pieces
- Moss patches in the humid area
Provide plenty of natural hiding spots. They'll utilise cover throughout the enclosure and feel more secure with options available.
Temperature: They tolerate a good range (18-26°C), making them suitable for room temperature conditions in most UK homes. They can handle cooler temperatures better than tropical species—brief drops to 15°C won't cause major problems, though consistent warmth promotes better breeding. Avoid sustained temperatures above 28°C.
Bioactive Use
Trachelipus caucasius work well as cleanup crew in appropriate bioactive setups.
Advantages:
- Larger size makes them efficient decomposers
- Peaceful temperament allows cohabitation
- Temperature tolerance suits varied bioactive environments
- Hardy nature means they establish reliably
- Good breeding ensures population maintenance
Suitable setups: Their temperature flexibility makes them suitable for a range of bioactive enclosures—from temperate setups to warmer tropical environments. They're particularly useful where temperature may fluctuate seasonally or where other species might struggle with cooler periods.
Considerations:
- Larger adults may be visible in display enclosures (advantage or disadvantage depending on preference)
- Cannot roll into a ball, so may be more vulnerable to predation by some reptiles than conglobating species
Mixed cleanup crews: They coexist peacefully with springtails and other isopod species. Their different niche and peaceful nature makes them suitable for diverse cleanup crew combinations.
Suitability
Trachelipus caucasius are suitable for keepers wanting a hardy, attractive species with minimal fuss.
Good choice for:
- Beginners wanting something slightly different from common species
- Keepers in homes with variable temperatures
- Those wanting a larger, visible isopod species
- Bioactive setups requiring temperature-tolerant cleanup crew
- Collectors building diverse collections
Not ideal for:
- Keepers specifically wanting conglobating (ball-rolling) species
- Extremely high-humidity tropical setups (better options exist)
Care level: Low difficulty. They're forgiving of husbandry variations, tolerate temperature fluctuation, breed reliably, and don't have demanding requirements. A good choice for developing isopod-keeping skills or for maintaining functional colonies without constant attention.
Value: Good value for an attractive, larger species. They offer interesting appearance and reliable breeding at a reasonable price point, making them practical for both collection and functional bioactive use.
