The Porcellionides pruinosus 'Tropical Grey/Powder Blue' is a popular and hardy species of isopod often called the Powder Blue Isopod, Tropical Grey Woodlouse, or Plum Woodlouse. This is the wild-type coloration of the species, known for its rapid movement, tolerance to varying humidity, and prolific breeding.
 
Key Characteristics
Appearance: The primary colour is a slate-grey or purplish-brown with a distinct pale blue or grey "bloom" or powdery look to the exoskeleton, which comes from fine, translucent scales. They have a smooth, segmented body and are fast-moving, using speed to escape rather than rolling into a tight ball.
Size: They are medium-sized isopods, typically reaching an adult length of 1 to 1.5 cm (about 0.4 to 0.6 inches).
Behavior: They are very active and often visible during the day, readily foraging on the surface. Their robust nature and efficiency as detritivores make them ideal for a clean-up crew in bioactive terrariums.
Origin: The species originated in Europe but has a widespread, global distribution due to human activity. 
 
Husbandry and Care
'Powder Blue' isopods are among the most beginner-friendly species due to their hardiness and high tolerance for a range of conditions. 
Habitat: A well-ventilated enclosure is best. A moisture gradient should be maintained, with one side kept damp using sphagnum moss and the other side allowed to be drier, as they do not require the high humidity of some tropical species.
Temperature & Humidity: They thrive in a wide range of temperatures from 15–28°C (60–82°F) and moderate humidity levels (45–60% RH are often tolerated, but they do best with access to a higher humidity retreat).
Diet: As primary detritivores, provide ample decaying organic matter as their main diet:
Main diet: Decaying hardwood leaf litter (oak, beech, magnolia) and rotting white wood.
Supplements: Offer protein sources like fish flakes or dried shrimp regularly.
Calcium: A constant source of calcium (cuttlebone or eggshells) is vital for their exoskeleton health.
Breeding: They are highly prolific breeders, with females capable of laying hundreds of eggs in their lifetime, quickly establishing a large colony.