Collins' Squirrel Monkey vs Common Rough Woodlouse

Saimiri collinsi compared with Porcellio scaber

Taxonomic Classification

Rank	Collins' Squirrel Monkey	Common Rough Woodlouse
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Chordata (Chordates)	Arthropoda (Arthropods)
Class	Mammalia (Mammals)	Malacostraca (Crustaceans)
Order	Primates (Primates)	Isopoda (Isopoda)
Family	Cebidae	Porcellionidae
Genus	Saimiri	Porcellio
Species	Saimiri collinsi	Porcellio scaber

Evolutionary Relationship

Collins' Squirrel Monkey and Common Rough Woodlouse share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Collins' Squirrel Monkey

LC — Least Concern

Common Rough Woodlouse

LC — Least Concern

Physical Characteristics

Attribute	Collins' Squirrel Monkey	Common Rough Woodlouse
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Collins' Squirrel Monkey

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

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).

Collins' Squirrel Monkey

<em>Saimiri collinsi</em>, commonly known as Collins' Squirrel Monkey, is a primate species belonging to the genus <em>Saimiri</em> within the family Cebidae. Squirrel monkeys are small, highly social New World primates known for their agility in forest canopies and their complex group dynamics. This species is assessed as Least Concern by major conservation bodies, indicating that its populations are not currently considered at high risk of decline, though ongoing deforestation and habitat fragmentation in Amazonian regions may affect future population stability. Collins' Squirrel Monkey inhabits diverse terrestrial and aquatic-adjacent environments typical of tropical forest ecosystems in South America. Specific country-level distributional records are not detailed in current documentation. Dietary information specific to this species has not been recorded, though squirrel monkeys in general are omnivorous, consuming insects, small vertebrates, fruits, and other plant material. Biological traits of this species remain poorly documented in the scientific literature. Research into the taxonomy and ecology of <em>Saimiri collinsi</em> continues to refine understanding of squirrel monkey diversity.

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.