Coimbra-Filho’s Titi vs Common Silver Hairgrass

Callicebus coimbrai compared with Aira caryophyllea

Taxonomic Classification

Rank	Coimbra-Filho’s Titi	Common Silver Hairgrass
Kingdom	Animalia (Animals)	Plantae (planta)
Phylum	Chordata (cordados)	Magnoliophyta (Flowering Plants)
Class	Mammalia (mamíferos)	Liliopsida (Monocots)
Order	Primates (Primates)	Poales (Grasses)
Family	Pitheciidae	Poaceae (Grass Family)
Genus	Callicebus	Aira
Species	Callicebus coimbrai	Aira caryophyllea

Conservation Status

Coimbra-Filho’s Titi

EN — Endangered

Common Silver Hairgrass

EN — Endangered

Physical Characteristics

Attribute	Coimbra-Filho’s Titi	Common Silver Hairgrass
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Coimbra-Filho’s Titi

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Common Silver Hairgrass

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical grasslands and savannas, and flooded grasslands and savannas, among 11 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Africa (Cameroon), Asia (Japan, South Korea), Europe (6 countries), North America (4 countries), Oceania and the Pacific (Australia), and South America (4 countries). Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Coimbra-Filho’s Titi

The Coimbra-Filho's Titi (Callicebus coimbrai), also known as Coimbra-Filho's Titi Monkey, is a small New World monkey in the family Pitheciidae, named in honour of the Brazilian primatologist Adelmar F. Coimbra-Filho. This titi monkey is endemic to the Atlantic Forest of northeastern Brazil, with its range restricted to the states of Sergipe and southern Alagoas—one of the most critically fragmented and threatened biomes on Earth. Adults are small, with reddish-brown fur on the flanks and upperparts, pale grey on the underparts, and an orange-red forehead band. Like all titi monkeys, Callicebus coimbrai is highly social, living in monogamous family groups of 2–5 individuals that engage in elaborate dawn duets and tail-twining behaviour as expressions of pair bonding. The species inhabits Atlantic Forest fragments, including lowland and highland forest patches, riverine gallery forest, and secondary growth, where it subsists on fruits, seeds, leaves, and occasional invertebrates. The Coimbra-Filho's Titi is classified as Endangered by the IUCN due to its severely fragmented range within one of the world's most deforested biomes, with less than 12% of original Atlantic Forest remaining, ongoing habitat loss from agricultural expansion, and small, isolated population sizes highly vulnerable to stochastic extinction events.

Common Silver Hairgrass

<em>Aira caryophyllea</em>, commonly known as Common Silver Hairgrass, is a slender annual grass belonging to the family Poaceae within the order Poales. This delicate grass is currently classified as Endangered on the IUCN Red List, reflecting significant conservation concern despite its historically broad distribution. It is typically found across a remarkable diversity of biome types, including tropical and subtropical moist broadleaf forests, grasslands, savannas, and flooded habitats, demonstrating notable ecological versatility. Its geographic range spans multiple continents, with documented populations in Africa (Cameroon), Asia (Japan, South Korea), Europe, North America, Australia, and South America. As an annual grass, it completes its life cycle within a single growing season, reproducing via wind-dispersed seeds. The inflorescence typically bears silvery, shimmering spikelets that give the species its common name. Biological traits such as average lifespan, body dimensions, and dietary specifics follow typical patterns for annual grasses — drawing nutrients from soil through root absorption rather than consuming other organisms. The endangered status suggests populations may be declining due to habitat loss, land-use change, or invasive species pressure across parts of its range.