vs Pacific Spiny-rat

Colacium sideropus compared with Proechimys decumanus

Key Differences

• is Not Evaluated while Pacific Spiny-rat is Near Threatened.

Taxonomic Classification

Rank		Pacific Spiny-rat
Kingdom	Protozoa (protozoa)	Animalia (Animals)
Phylum	Euglenozoa (Euglenozoa)	Chordata (Chordates)
Class	Euglenoidea (Euglenoidea)	Mammalia (Mammals)
Order	Euglenida (Euglenida)	Rodentia (Rodents)
Family	Euglenaceae	Echimyidae
Genus	Colacium	Proechimys
Species	Colacium sideropus	Proechimys decumanus

Conservation Status

NE — Not Evaluated

Pacific Spiny-rat

NT — Near Threatened

Physical Characteristics

Attribute		Pacific Spiny-rat
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Habitat

Native to Europe and South America, inhabiting ecosystems characteristic of the region.

Range

Distributed across Brazil and Sweden.

Pacific Spiny-rat

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Range

Found in Ecuador. Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

Colacium sideropus is a microscopic euglenoid protist belonging to the family Euglenaceae, characterized by its sessile, colonial lifestyle attaching to aquatic invertebrates and zooplankton. Members of the genus Colacium are distinguished from free-swimming euglenoids by their stalked or clustered growth form, anchoring to the bodies of crustaceans such as copepods and cladocerans in freshwater environments. Like other photosynthetic euglenoids, Colacium possesses chloroplasts derived from secondary endosymbiosis with a green alga, allowing it to perform photosynthesis under favorable light conditions. The relationship with host invertebrates is generally considered epibiotic rather than parasitic, with the protist colonizing the external surfaces of its host without causing significant harm. Colacium sideropus occurs in freshwater lakes, ponds, and slow-moving streams where its zooplankton hosts are abundant. Its ecological role includes contributing to microbial food webs and nutrient cycling within freshwater ecosystems. As with many microscopic protists, its true distribution and abundance are difficult to assess from macroscopic surveys, and it is likely globally distributed wherever suitable hosts exist in freshwater habitats.