Pill Bug / Roly Poly
Scientific Name: Armadillidium vulgare (Common Pill Bug) is a very common species, though there are many other species within the Armadillidiidae family.
Order & Family: Order: Isopoda; Family: Armadillidiidae (for pill bugs like Armadillidium vulgare) or Porcellionidae (for common sow bugs, which are similar but cannot roll into a complete ball). The one in the picture appears to be a pill bug.
Size: Typically 6 to 18 mm (0.2 to 0.7 inches) in length.
Natural Habitat
They thrive in humid environments and are typically found under rocks, logs, leaf litter, rotting wood, and other garden debris. They can also be found in damp basements or crawl spaces indoors.
Diet & Feeding
Mainly detritivores, feeding on decaying organic matter such as dead leaves, wood, and other plant debris. They play a significant role in decomposition.
Behavior Patterns
They are nocturnal and prefer damp, dark environments. When disturbed, many species can roll into a tight ball, which is why they are often called "pill bugs" or "rolly pollies". This behavior is a defense mechanism against predators. They reproduce by laying eggs in a brood pouch (marsupium) on the female's underside.
Risks & Benefits
Generally harmless to humans. They do not bite, sting, or spread diseases. In gardens, they can sometimes cause minor damage to young plants or seedlings, especially in high populations, by chewing on tender shoots. However, their primary benefit is their role as decomposers, helping to break down organic matter and return nutrients to the soil. They are also an important food source for many small predators.
Identified on: 7/2/2025