Soil Isopods (Cubaris/Troglodillo sp)

Soil Isopods are one of the most distinctively-coloured isopods in the entire UK hobby — large, flat, dark purple-to-black bodied animals with striking white antennae that create immediate visual contrast. Originally classified as Cubaris sp. and still widely sold under that name in the trade, recent taxonomic work has reclassified them as Troglodillo sp. — though they're often listed dual-named as you'll see across UK retailers. Their dark colouration and dramatic appearance have earned them the affectionate nicknames "Gothic Isopods" and "The Black Evil" in some hobby circles, though their unexpectedly endearing "rubber duck face" personality undercuts the moody aesthetic.

What makes Soil Isopods particularly worth keeping is the combination: substantial size (15–20 mm — among the larger Cubaris/Troglodillo species available), genuinely unique colouration that doesn't compete visually with any other isopod in a typical collection, and surprisingly accessible care for what was once considered a rare species. They're rated Medium difficulty rather than high-maintenance like premium cave Cubaris, making them an excellent step-up choice for keepers wanting something visually distinctive without ultra-precision husbandry.

Available in groups of 5, 10, or 20. Captive-bred stock from established UK colonies. Currently on sale at 30% off — exceptional value for this distinctive species. Mixed sizes included to give your colony immediate breeding potential.

Quick Care Summary

• Scientific Name: Troglodillo sp. (formerly classified as Cubaris sp.)
• Common Names: Soil Isopod, Gothic Isopod, "The Black Evil", Black Cubaris
• Family: Armadillidae
• Origin: Vietnam — tropical forests, shaded humid environments
• Adult Size: 15–20 mm — among the larger Troglodillo species
• Lifespan: 2–3 years typical
• Difficulty: Medium — accessible for keepers stepping up from beginner species
• Temperature: 23–27°C (UK room temperature works year-round with minor adjustment)
• Humidity: 60–80% — moderate to high, with moisture gradient
• Ventilation: Medium — good airflow with humidity retention
• Conglobation: Yes — rolls into a tight ball when disturbed
• Behaviour: Surface-active on flat rocks, prefers shade, less active in dry conditions
• Breeding: Moderate — slower than common Cubaris but achievable with proper conditions

What Makes Soil Isopods Special

Several factors make Soil Isopods one of the more visually distinctive choices in the UK hobby:

The colouration is genuinely unique. Where most Cubaris display warm tones, banded patterns, or muted greys, Soil Isopods deliver a dark purple-to-black body that stands apart from anything else in a typical collection. Combined with their bright white antennae, the contrast is immediate and unmistakable. Against natural substrate and leaf litter, they look almost like miniature armoured creatures — hence the "Gothic" and "Black Evil" nicknames.

The "rubber duck face" charm. Despite the moody marketing, Soil Isopods have surprisingly adorable faces when viewed up close — similar to the famous Rubber Ducky Cubaris in profile. The contrast between their dramatic dark colouration and their cute facial structure makes them genuinely engaging animals to keep and observe.

Substantial size with proper presence. At 15–20 mm, Soil Isopods are noticeably larger than many common Cubaris species. The size combined with their distinctive colouration makes them genuinely viable as display animals — observable from a distance rather than requiring close inspection.

Taxonomic interest. Their recent reclassification from Cubaris to Troglodillo reflects ongoing scientific work in isopod taxonomy. Keeping them connects you to a species that's still being studied and understood — meaningful for serious collectors interested in the science behind their hobby.

Distinctive behavioural patterns. Unlike many Cubaris that hide constantly, Soil Isopods prefer flat rock surfaces and remain relatively visible in their preferred microhabitat. Their seasonal activity patterns (more active in wet conditions, less active during dry periods) reflect their tropical Vietnamese origins and add character to colony observation.

Conglobation. Like other Cubaris-type isopods, Soil Isopods roll into tight defensive balls when threatened. The combination of their dark colouration and the conglobation behaviour creates a distinctive defensive display.

Accessible Medium difficulty. While they're more demanding than entry-level Cubaris like C. murina, they're significantly more forgiving than ultra-premium species like Rubber Ducky or Lemon Blue. This makes them an excellent stepping stone for keepers moving from accessible Cubaris into more advanced species.

Setting Up the Enclosure

A plastic or glass enclosure works well — choose based on display preference and budget. For a starter colony of 5–10, a 6–8 quart container is adequate; scale up for larger groups. Plastic tubs with clip-lock lids hold humidity well; glass terrariums offer better display.

Ventilation balance is key. Provide small ventilation holes for airflow — enough to prevent mould but not so much that humidity drops significantly. Cross-ventilation through small holes on opposite sides works better than wide mesh sections. Cover holes with fine mesh to prevent escapes.

Keep the enclosure in a dim, shaded area — Soil Isopods prefer low-light conditions reflecting their natural forest floor habitat. Direct sunlight or bright artificial light causes stress.

Browse our accessories collection for appropriate enclosures, vents, and other essentials.

Substrate — ABG Mix Recommended

The ABG (Atlanta Botanical Garden) substrate mix is ideal for Soil Isopods and many other tropical isopods. It balances moisture retention, drainage, and nutrition in a way that single-component substrates can't match.

ABG mix composition:

• Orchid bark
• Charcoal
• Tree fern fibre
• Peat moss
• Sphagnum moss

Substrate depth: At least 7–10 cm. Soil Isopods burrow during moulting and breeding, so adequate depth supports natural behaviour.

Calcium throughout: Mix powdered limestone throughout the substrate. While Soil Isopods aren't strictly cave-origin like some Cubaris, they still benefit from constant calcium availability for healthy moulting.

Top layer: Generous hardwood leaf litter and pieces of decaying rotting wood — both provide food value and structural complexity. Add multiple cork bark hides spread throughout, plus flat rocks or limestone pieces (they prefer flat rock surfaces to many other hide types).

Humidity and Temperature

Maintain humidity at 60–80% with a moisture gradient — one side damper with sphagnum moss patches, the other slightly drier. Avoid waterlogging — the substrate should be visibly damp but never have standing water at the bottom.

Soil Isopods become less active during drier periods and noticeably more active when humidity is high (mimicking the rainy seasons in their natural Vietnamese habitat). Don't worry if your colony seems sluggish during dry household conditions — they'll perk up when conditions return to ideal.

Temperature should be maintained at 23–27°C. UK summer temperatures often fall within range; winter heating may be needed if your home gets cold. A low-wattage heat mat on the side of the enclosure (never underneath, to avoid drying substrate) connected to a thermostat keeps the colony stable.

Stable conditions matter more than hitting any specific point within the comfort range — sudden temperature swings cause stress.

Diet

Soil Isopods are omnivorous detritivores with broad appetites:

• Primary diet (always available): Decaying hardwood leaf litter, rotting white wood, dried plant material, sphagnum moss
• Vegetables (1–2x weekly): Carrot, courgette, sweet potato, butternut squash, cucumber, fresh greens. Replace within 24–48 hours.
• Protein (essential — 1–2x weekly): Meat scraps (small amounts), mushrooms, fish flakes, dried daphnia, freeze-dried shrimp. Protein supplementation supports healthy moulting and breeding.
• Calcium (always available): Cuttlefish bone, crushed eggshells, powdered limestone, calcium powder. Provide constantly — don't let calcium sources run out.
• Supplements (1–2x monthly): Calcium powder or cuttlefish bone as alternative supplements.

Browse our accessories collection for the full range of protein supplements and substrate components.

Breeding

Soil Isopods breed at a moderate rate — slower than common Cubaris murina but achievable with proper conditions. They're considered "rare and hard to breed" by some keepers, but this reflects the demanding requirements rather than fundamental difficulty.

For breeding success:

• Stable temperatures (23–27°C, optimal around 24–26°C)
• Consistent humidity (70–80%)
• Deep substrate (7–10 cm) for burrowing and security
• Abundant calcium availability throughout
• Regular protein supplementation
• Plenty of flat hiding surfaces
• Minimal disturbance during establishment
• Larger starter groups (10+) provide better genetic diversity

Resist the urge to dig through substrate looking for offspring. Undisturbed colonies breed more reliably. Allow 2–3 months for new colonies to settle before expecting significant breeding activity.

Pair With Springtails

Add a thriving springtail culture to any Soil Isopod setup. Springtails handle mould and microbial growth at a scale isopods can't manage, particularly important in humid setups where mould can develop quickly. They coexist peacefully with Soil Isopods and form an essential cleanup partnership for tropical Cubaris-type setups.

Important Note on Species Mixing

Don't mix Soil Isopods with other isopod species in the same enclosure. Mixed-species setups frequently lead to one species dominating and gradually outcompeting the other. This is particularly relevant for Soil Isopods because their slower breeding rate makes them vulnerable to being outcompeted by faster-breeding species. Keep them as a standalone colony for best results.

Who Should Buy Soil Isopods?

Ideal for:

• Keepers stepping up from accessible Cubaris (like C. murina) into more distinctive species
• Collectors building Cubaris/Troglodillo collections wanting a uniquely-coloured addition
• Anyone who appreciates dark, dramatic colouration over bright designer morphs
• Display setup enthusiasts wanting larger, visible animals
• Patient keepers willing to wait through slower establishment for distinctive results
• Bioactive vivarium owners with tropical conditions year-round

Not ideal for:

• Complete beginners — start with hardier species first
• Mixed-species enclosures (they don't mix well)
• Anyone wanting fast-breeding colonies
• Setups where temperature can't be maintained reliably
• Brightly-lit enclosures (they prefer shade)

Realistic Expectations

Soil Isopods take time to establish. Allow 2–3 months for new colonies to settle and begin breeding. Don't panic during this initial period — focus on stable conditions and let them adapt.

Activity levels vary with humidity. During dry household periods, you may see less surface activity; during wetter conditions, they'll be more visible and active. This is normal seasonal-mimicking behaviour, not a sign of stress.

The dramatic dark purple-to-black colouration develops with age. Newly arrived juveniles may appear slightly lighter or more grey-toned than mature adults. Given 2–3 months of stable conditions and good nutrition, the full dark colouration develops properly. Customer feedback consistently describes them as "very cool flat isopods" — distinctive enough to stand out in any collection.

Building Your Setup

A complete Soil Isopod setup needs ABG-style substrate components, calcium-rich materials, generous leaf litter, and protein supplements. Browse our accessories collection for everything you need — enclosures, ventilation, leaf litter, calcium (cuttlebone, limestone), and protein supplements.

Browse the full Cubaris collection for related species, or explore our Troglodillo collection for other species in the newly-classified genus.