Clustered Stonewort vs Common Yellow Conch

Tolypella glomerata compared with Agapeta hamana

Key Differences

• Clustered Stonewort is Vulnerable while Common Yellow Conch is Least Concern.

Taxonomic Classification

Rank	Clustered Stonewort	Common Yellow Conch
Kingdom	Plantae (Plants)	Animalia (Animals)
Phylum	Charophyta (Charophyta)	Arthropoda (Arthropods)
Class	Charophyceae (Charophyceae)	Insecta (Insects)
Order	Charales (Charales)	Lepidoptera (Butterflies & Moths)
Family	Characeae	Tortricidae
Genus	Tolypella	Agapeta
Species	Tolypella glomerata	Agapeta hamana

Conservation Status

Clustered Stonewort

VU — Vulnerable

Common Yellow Conch

LC — Least Concern

Physical Characteristics

Attribute	Clustered Stonewort	Common Yellow Conch
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Clustered Stonewort

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, and Sweden. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Common Yellow Conch

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

Clustered Stonewort

Tolypella glomerata, the clustered stonewort, is a charophyte alga in the family Characeae, found in calcareous, nutrient-poor freshwater habitats including lakes, ponds, ditches, and slow-flowing water in northwestern and northern Europe. Charophytes are macroscopic green algae with a distinctive whorl-like arrangement of branches and a complex, plant-like structure that distinguishes them from other algae. T. glomerata is encrusted with calcium carbonate deposits (hence 'stonewort'), giving it a pale, grey-green appearance and rough texture. The species colonizes clear, low-nutrient water over fine sediment or gravel substrates where competition from vascular plants is reduced by nutrient limitation. It is listed as Vulnerable by the IUCN, reflecting significant declines driven by eutrophication (nutrient enrichment from agriculture and sewage), which promotes the growth of vascular plants and phytoplankton that shade out stoneworts. Drainage, water abstraction, and peat cutting also threaten its habitats. Charophyte diversity has declined substantially across lowland Europe and North America over the past century, with many species becoming locally extinct from sites they once colonized.

Common Yellow Conch

<em>Agapeta hamana</em>, the common yellow conch moth, is a small moth in the family Tortricidae. It is widely distributed across Europe and central Asia, ranging from Britain and Scandinavia eastward through much of the Palearctic region. The species inhabits dry grasslands, heathlands, chalk downlands, and scrubby habitats where its larval host plants are found. Adult moths display distinctive pale yellow to golden-yellow forewings with irregular brown or reddish-brown markings near the wingtip, forming a pattern that resembles the shell of a conch, lending the species its common name. The wingspan typically measures around 15–22 mm. Biological traits such as average adult lifespan, precise body weight, and detailed population data remain poorly documented in consolidated scientific literature. Larvae feed internally on the roots of thistles and knapweeds, particularly <em>Centaurea</em> and <em>Cirsium</em> species. Adults fly from June to August and are frequently attracted to light. <em>Agapeta hamana</em> has been investigated as a potential biological control agent for invasive knapweed species in North America, where it has been introduced experimentally. The species is assessed as Least Concern given its broad distribution and stable habitat associations.

Shared Countries

Both species can be found in 3 countries:

🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden