Common Pill Woodlouse vs Green Sea Turtle

Armadillidium vulgare compared with Chelonia mydas

Key Differences

• Common Pill Woodlouse is Near Threatened while Green Sea Turtle is Endangered.

Taxonomic Classification

Rank	Common Pill Woodlouse	Green Sea Turtle
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (Arthropods)	Chordata (Chordates)
Class	Malacostraca (Crustaceans)	Reptilia (Reptiles)
Order	Isopoda (Isopoda)	Testudines (Turtles & Tortoises)
Family	Armadillidiidae	Cheloniidae (Sea Turtles)
Genus	Armadillidium	Chelonia (Green Sea Turtles)
Species	Armadillidium vulgare	Chelonia mydas

Evolutionary Relationship

Common Pill Woodlouse and Green Sea Turtle share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Common Pill Woodlouse

NT — Near Threatened

Green Sea Turtle

EN — Endangered

Population: ~85.0K

Trend: Decreasing ↓

Physical Characteristics

Attribute	Common Pill Woodlouse	Green Sea Turtle
Diet	—	Herbivore
Average Lifespan	—	80 years
Average Length	—	1.2 m
Average Weight	—	200.0 kg

Habitat & Geographic Range

Common Pill Woodlouse

Habitat

Typically found in marine, freshwater, and terrestrial environments.

Range

Widely distributed across Africa (South Africa), Asia (Japan), Europe (6 countries), and North America (United States). Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

Green Sea Turtle

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and tropical and subtropical grasslands and savannas, among 8 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Distributed across Australia, Brazil, Costa Rica, Indonesia, and Mexico. Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Common Pill Woodlouse

<em>Armadillidium vulgare</em>, the common pill woodlouse, is a terrestrial isopod crustacean in the family Armadillidiidae, widely recognised for its ability to roll into a tight sphere when disturbed, a defensive behaviour that gives it the common name "pill bug" or "roly-poly." Unlike most crustaceans, it is fully adapted to life on land, breathing through modified gill-like structures that must remain moist. The species inhabits a broad range of environments, typically occurring under rocks, leaf litter, decaying wood, and in gardens and agricultural land, where it feeds on decomposing organic matter, playing an important role in nutrient cycling. <em>Armadillidium vulgare</em> is distributed across Europe, parts of Asia including Japan, South Africa, and North America including the United States, reflecting its success as a cosmopolitan species often transported inadvertently by human activity. It is assessed as Near Threatened on the IUCN Red List. Biological traits such as average lifespan, precise body dimensions, and detailed dietary composition across its range remain poorly documented in the scientific literature. Females brood their young in a marsupium, and the species is capable of parthenogenesis under certain conditions, contributing to reproductive flexibility.

Green Sea Turtle

The green sea turtle is one of the largest sea turtles. They are named for the green color of their cartilage and fat, not their shells.