Arctic grass vs Common Rough Woodlouse

Arctagrostis latifolia compared with Porcellio scaber

Key Differences

• Arctic grass is Near Threatened while Common Rough Woodlouse is Least Concern.

Taxonomic Classification

Rank	Arctic grass	Common Rough Woodlouse
Kingdom	Plantae (Plants)	Animalia (Animals)
Phylum	Magnoliophyta (Flowering Plants)	Arthropoda (Arthropods)
Class	Liliopsida (Monocots)	Malacostraca (Crustaceans)
Order	Poales (Grasses)	Isopoda (Isopoda)
Family	Poaceae (Grass Family)	Porcellionidae
Genus	Arctagrostis	Porcellio
Species	Arctagrostis latifolia	Porcellio scaber

Conservation Status

Arctic grass

NT — Near Threatened

Common Rough Woodlouse

LC — Least Concern

Physical Characteristics

Attribute	Arctic grass	Common Rough Woodlouse
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Arctic grass

Habitat

Typically found in grasslands, wetlands, forests, and cultivated landscapes.

Range

Distributed across Norway and Sweden. Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

Common Rough Woodlouse

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and deserts and xeric shrublands within the Indomalayan biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Africa (South Africa), Asia (Japan, Sri Lanka), Europe (5 countries), North America (United States), and South America (Brazil).

Arctic grass

The Arctic grass (Arctagrostis latifolia) is a species in the genus Arctagrostis. It is currently classified as Near Threatened on the IUCN Red List. Typically found in grasslands, wetlands, forests, and cultivated landscapes.

Common Rough Woodlouse

<em>Porcellio scaber</em>, the common rough woodlouse, is a terrestrial isopod crustacean in the family Porcellionidae. One of the most widespread and abundant woodlouse species in the world, it has established itself across Europe, the Americas, Asia, Australia, and numerous oceanic islands, including populations documented in Belgium, Brazil, Denmark, Japan, and Norway. This synanthropic species typically inhabits decaying leaf litter, rotting wood, compost heaps, under stones, and in the soil of gardens, forests, and human-modified landscapes. It thrives in moist, sheltered microhabitats and shows some tolerance for drier conditions compared to related species. As a detritivore, the common rough woodlouse feeds primarily on decaying organic matter including leaf litter, rotting wood, fungi, and plant debris, playing a significant role in nutrient cycling and decomposition processes. The species reproduces sexually, with females brooding eggs and juveniles in a specialized brood pouch. Assessed as Least Concern by the IUCN, its cosmopolitan distribution and high adaptability make it one of the most ecologically resilient terrestrial isopods. It is easily identified by its rough, grey to dark brown dorsal surface with pale lateral markings. Biological traits such as average lifespan and typical body length remain variable across populations and are not uniformly documented in standardized databases.

Shared Countries

Both species can be found in 2 countries:

🇳🇴 Norway 🇸🇪 Sweden