common bubble snail vs Common Red-legged Robberfly

Akera bullata compared with Dioctria rufipes

Taxonomic Classification

Rank	common bubble snail	Common Red-legged Robberfly
Kingdom same	Animalia (hayvan)	Animalia (hayvan)
Phylum	Mollusca (Yumuşakçalar)	Arthropoda (Eklem bacaklılar)
Class	Gastropoda (Karından bacaklılar)	Insecta (böcek)
Order	Aplysiida (Aplysiida)	Diptera (Çift kanatlılar)
Family	Akeridae	Asilidae
Genus	Akera	Dioctria
Species	Akera bullata	Dioctria rufipes

Evolutionary Relationship

common bubble snail and Common Red-legged Robberfly share a common ancestor at the Kingdom level: Animalia. (hayvan)

Conservation Status

common bubble snail

LC — Least Concern

Common Red-legged Robberfly

LC — Least Concern

Physical Characteristics

Attribute	common bubble snail	Common Red-legged Robberfly
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

common bubble snail

Habitat

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

Range

Distributed across Denmark, Norway, Portugal, and Sweden.

Common Red-legged Robberfly

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

common bubble snail

The common bubble snail (<em>Akera bullata</em>) is a marine gastropod mollusc found in the coastal waters of Denmark, Norway, Portugal, and Sweden. This species typically inhabits terrestrial and aquatic environments including forests and freshwater-adjacent marine areas, often occurring in shallow subtidal and intertidal zones of temperate European seas. It is classified as Least Concern on the IUCN Red List. As a member of the family Akeridae, the common bubble snail is characterized by its thin, fragile shell and its ability to swim briefly by flapping its large, wing-like parapodia. The species often forages on algae and detritus in sandy and muddy seafloor habitats, particularly in sheltered bays and estuaries. The common bubble snail typically aggregates in large numbers during the spawning season, producing gelatinous egg masses. Biological traits of this species remain poorly documented in the scientific literature.

Common Red-legged Robberfly

<em>Dioctria rufipes</em>, the common red-legged robberfly, is a predatory fly in the family Asilidae, order Diptera. It is distributed across northwestern Europe, with confirmed records from Belgium, Denmark, Norway, and Sweden, typically favoring woodland edges, hedgerows, and meadows with abundant vegetation. The species is assessed as Least Concern on the IUCN Red List, reflecting stable populations across its European range. Robberflies in the genus Dioctria are slender, elongated flies characterized by a distinctive long proboscis used to inject paralyzing saliva into prey. <em>Dioctria rufipes</em> typically hunts smaller flying insects, including midges, small flies, and other soft-bodied arthropods, ambushing prey from resting perches on vegetation and capturing it mid-flight. Adults are typically active from late spring to early autumn, coinciding with peak insect activity. The red or reddish-orange coloration of the hind femora is the diagnostic feature that gives this species its common name. Larvae develop in soil or decaying wood, where they are believed to be predatory on other invertebrate larvae. Biological traits such as precise lifespan, body measurements, and diet composition remain poorly documented in quantitative studies. The species is considered an important component of invertebrate predator guilds in European agricultural landscapes.

Shared Countries

Both species can be found in 3 countries:

🇩🇰 Denmark 🇳🇴 Norway 🇸🇪 Sweden