Yellow-Margined Isopod — Fact Sheet

Porcellio flavomarginatus · Yellow-Margined Isopod

📋 At a glance

🏠 Enclosure

• For 10-20 animals: at least 30 × 20 × 15 cm with several close-fitting shelters.
• Provide strong high and low cross-ventilation, with most openings over the predominantly dry side.
• Quarantine for 30-60 days and record the supplier’s exact locality wording; do not merge verified Crete stock with unproven animals.

🪨 Enclosure furniture

• Use 5-7 cm of mineral-rich pesticide-free soil, leaf mould, and rotten hardwood.
• Add securely supported limestone, cork flats, dry hardwood leaves, and one small moss pocket at the wet end.
• Keep cuttlebone or calcium carbonate continuously; do not replace edible substrate with sterile rock or coir.

💡 Lighting

• UVB is not required.
• Use 10-14 hours of diffuse seasonal light with shade below cork and stones.
• Avoid direct sun and heating display lamps; a Mediterranean label does not make overheating safe.

🌡️ Temperature

• Local warm point: 23-26 °C

• Warm zone: 18-26 °C

• Cool zone: 16-21 °C

• Night: 16-22 °C

• Normal cool-season room temperatures are acceptable; sustained temperatures above 28 °C are unsafe.

• If heat is necessary, warm one outer wall and keep the damp end and substrate base cooler.

💧 Humidity & water

• Use about 40-65% RH only as a guide; the localized hydration refuge is the essential feature.
• Keep roughly one-quarter damp below moss and cork while the larger surface area dries and receives strong airflow.
• No water dish. Add water only at the damp end; an entirely wet box promotes fungus, while a dry base kills mancae.

🥬 Diet

Feed freely:

• Decayed hardwood leaves
• Soft rotten hardwood

In moderation:

• Carrot, squash, sweet potato, courgette, mushroom, or dried nettle two or three times weekly
• A small weekly serving of dried shrimp, gammarus, or fish food

Avoid:

• Waterlogged substrate, unstable stones, seasoned food, pesticide-contaminated leaves
• Heavy protein feeding and wet remains older than 24-48 hours

Supplements:

• Cuttlebone, porous limestone, or plain calcium carbonate permanently
• Do not confuse a calcium-rich setup with a sterile rock-only enclosure

🩺 Health — warning signs

• Incomplete moults → deep damp refuge lost or enclosure overheated
• Fungal growth and wall climbing → wet footprint too large or ventilation inadequate
• Slow growth → poor-quality leaf litter or insufficient rotten wood
• Crushed animals → limestone placed on loose, undermined substrate
• Crete label lost → mixed lines or undocumented transfers

Isolate a declining line and seek an invertebrate-experienced exotic veterinarian or specialist laboratory if correcting moisture and ventilation does not halt losses.