common whorl snail vs koala

Vertigo pygmaea compared with Phascolarctos cinereus

Key Differences

• common whorl snail is Near Threatened while koala is Vulnerable.

Taxonomic Classification

Rank	common whorl snail	koala
Kingdom same	Animalia (动物界)	Animalia (动物界)
Phylum	Mollusca (软体动物门)	Chordata (脊索动物门)
Class	Gastropoda (腹足纲)	Mammalia (哺乳動物)
Order	Stylommatophora (柄眼目)	Diprotodontia (雙門齒目)
Family	Vertiginidae	Phascolarctidae (Koalas)
Genus	Vertigo	Phascolarctos (Koalas)
Species	Vertigo pygmaea	Phascolarctos cinereus

Evolutionary Relationship

common whorl snail and koala share a common ancestor at the Kingdom level: Animalia. (动物界)

Conservation Status

common whorl snail

NT — Near Threatened

koala

VU — Vulnerable

Population: ~100.0K

Trend: Decreasing ↓

Physical Characteristics

Attribute	common whorl snail	koala
Diet	—	Herbivore
Average Lifespan	—	15 years
Average Length	—	75 cm
Average Weight	—	10.0 kg

Habitat & Geographic Range

common whorl snail

Habitat

Typically found in terrestrial and aquatic habitats including forests and freshwater.

Range

Found across Europe (9 countries) and North America (United States). Listed as Near Threatened, this species requires ongoing monitoring to prevent population decline.

koala

Habitat

Typically found in grasslands, forests, and vegetated habitats.

Range

Found in Australia. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

common whorl snail

<em>Vertigo pygmaea</em>, commonly known as the common whorl snail, is a minute land snail in the family Vertiginidae, listed as Near Threatened on the IUCN Red List, reflecting documented population declines attributable to habitat loss, agricultural intensification, and wetland drainage across its European and North American range. The species occurs across much of Europe and parts of the United States, typically inhabiting short-sward calcareous grasslands, chalk and limestone downlands, damp meadows, and the bases of grassy slopes where the vegetation structure is open and low-growing. <em>Vertigo pygmaea</em> is among the smallest terrestrial mollusks, with a shell typically measuring only 1.5–2 mm in height — a feature shared by all members of the genus Vertigo. Despite its tiny size, the shell is complex, with multiple internal tooth-like lamellae visible within the aperture that are used in species identification. The species typically feeds on decaying plant material, algae, and fungi associated with soil and leaf litter microhabitats. It requires specific microhabitat conditions including moderate soil moisture and an abundance of calcium for shell formation. Biological traits including average lifespan, precise shell dimensions, and mass remain poorly documented in standardized databases. Conservation efforts for <em>Vertigo pygmaea</em> typically focus on maintaining and restoring calcareous grassland habitats through appropriate grazing management regimes.

koala

澳大利亚东部和东南部的标志性有袋类动物，体重最大可达15千克，为了节省低热量桉树叶食物所提供的能量，每天最多睡眠22小时。高度特化，能够处理会致大多数其他哺乳动物死亡的有毒桉树成分，拥有专门适应解毒功能的肠道微生物群。因衣原体病、栖息地开发和气候变化导致种群锐减，2022年被列为濒危物种。