Common Pill Woodlouse vs Onca

Armadillidium vulgare compared with Panthera onca

Taxonomic Classification

Rank	Common Pill Woodlouse	Onca
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (artrópode)	Chordata (cordados)
Class	Malacostraca (Crustaceans)	Mammalia (mamíferos)
Order	Isopoda (Isópodos)	Carnivora (carnívoros)
Family	Armadillidiidae	Felidae (Cats)
Genus	Armadillidium	Panthera (Big Cats)
Species	Armadillidium vulgare	Panthera onca

Evolutionary Relationship

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

Conservation Status

Common Pill Woodlouse

NT — Near Threatened

Onca

NT — Near Threatened

Population: ~64.0K

Trend: Decreasing ↓

Physical Characteristics

Attribute	Common Pill Woodlouse	Onca
Diet	—	Carnivore
Average Lifespan	—	15 years
Average Length	—	1.9 m
Average Weight	—	100.0 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.

Onca

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 6 distinct biome types spanning the Neotropic and Oceanian realms. Populations are also found in montane and highland environments at higher elevations.

Range

Distributed across Colombia, Ecuador, and Venezuela. Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

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.

Onca

O maior felino das Américas, atingindo até 100 kg com corpo robusto e musculoso e pelagem com padrão de rosetas característico. Encontrado do México até a América do Sul, com populações mais expressivas na Amazônia e no Pantanal. Nadadores poderosos e predadores de topo, os jaguares desempenham papel fundamental na regulação das populações de presas. Classificado como Quase Ameaçado, com sua área de ocorrência diminuindo devido ao desmatamento.