Cliff Mining Bee vs Common Quaking Grass

Andrena thoracica compared with Briza media

Key Differences

Cliff Mining Bee is Extinct while Common Quaking Grass is Vulnerable.

Taxonomic Classification

Rank	Cliff Mining Bee	Common Quaking Grass
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Arthropoda (Arthropods)	Magnoliophyta (Flowering Plants)
Class	Insecta (Insects)	Liliopsida (Monocots)
Order	Hymenoptera (Ants, Bees & Wasps)	Poales (Grasses)
Family	Andrenidae	Poaceae (Grass Family)
Genus	Andrena	Briza
Species	Andrena thoracica	Briza media

Conservation Status

Cliff Mining Bee

EX — Extinct

Common Quaking Grass

VU — Vulnerable

Physical Characteristics

Attribute	Cliff Mining Bee	Common Quaking Grass
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Cliff Mining Bee

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Denmark, Luxembourg, Norway, and Sweden.

Common Quaking Grass

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, temperate grasslands and steppes, and flooded grasslands and savannas, among 6 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (Japan), Europe (7 countries), North America (Canada, United States), and South America (Argentina). Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Cliff Mining Bee

The Cliff Mining Bee, Andrena species in the family Andrenidae, is a solitary ground-nesting bee that excavates tunnels in cliff faces, earthen banks, and compacted sandy or loamy soils, where the loose or friable substrates exposed in cliff profiles provide ideal nesting conditions. Mining bees in the genus Andrena are among the most species-rich solitary bee genera in the world, with hundreds of species across the Holarctic region, many narrowly specialized in their choice of pollen host plants. Female cliff mining bees construct vertical or angled burrows in cliff faces, with lateral cells off the main shaft, each containing a pollen ball and a single egg. Males are typically smaller and emerge before females to establish territories near nesting sites. Many Andrena species are oligolectic, collecting pollen from only a small number of plant species, making their populations sensitive to the availability of specific flowering plants in the landscape surrounding nesting areas. Cliff and bank nesting habitats provide well-drained, sun-warmed substrates essential for brood development. The loss of natural cliff faces and earthen banks to development, vegetation succession, and quarrying reduces available nesting habitat for cliff mining bees.

Common Quaking Grass

The Common Quaking Grass, <em>Briza media</em>, is a perennial grass in the family Poaceae, native to Europe and parts of Asia and introduced to North America and South America. It is a characteristic species of ancient, species-rich calcareous grasslands, meadows, and chalk downlands, where it typically grows in well-drained, nutrient-poor soils in full sun. The species is easily recognized by its heart-shaped, flattened spikelets that hang on delicate, hair-like stalks and tremble in the slightest breeze, producing the distinctive quaking motion that gives the genus its common name. The spikelets are typically pale green when immature, turning golden-brown as they ripen, and the whole inflorescence is highly ornamental. <em>Briza media</em> is an important component of calcareous grassland communities, providing structure and seed resources for invertebrates and birds. It is sensitive to agricultural improvement and is often used as an indicator of long-undisturbed grasslands. The species is assessed as Vulnerable on the IUCN Red List, reflecting declines linked to habitat loss, agricultural intensification, and conversion of traditional grasslands. Biological traits such as average lifespan, body size, and specific dietary preferences remain poorly documented for this species.