Common Red-legged Robberfly vs Laysan Duck

Dioctria rufipes compared with Anas laysanensis

Key Differences

• Common Red-legged Robberfly is Least Concern while Laysan Duck is Critically Endangered.

Taxonomic Classification

Rank	Common Red-legged Robberfly	Laysan Duck
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (Arthropods)	Chordata (Chordates)
Class	Insecta (Insects)	Aves (Birds)
Order	Diptera (Diptera)	Anseriformes (Anseriformes)
Family	Asilidae	Anatidae
Genus	Dioctria	Anas
Species	Dioctria rufipes	Anas laysanensis

Evolutionary Relationship

Common Red-legged Robberfly and Laysan Duck share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Common Red-legged Robberfly

LC — Least Concern

Laysan Duck

CR — Critically Endangered

Physical Characteristics

Attribute	Common Red-legged Robberfly	Laysan Duck
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Common Red-legged Robberfly

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

Laysan Duck

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, temperate coniferous forests, and Mediterranean forests and woodlands within the Palearctic biogeographic realm. Populations are also found in montane and highland environments at higher elevations.

Range

Distributed across Belgium, France, Netherlands, Norway, and United Kingdom. Currently classified as Critically Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

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.

Laysan Duck

Laysan Duck (Anas laysanensis) is classified as Critically Endangered (CR) on the IUCN Red List. Facing an extremely high risk of extinction in the wild due to severe population decline and habitat loss.

Shared Countries

Both species can be found in 2 countries:

🇧🇪 Belgium 🇳🇴 Norway