blue whale vs Common Red-legged Robberfly

Balaenoptera musculus compared with Dioctria rufipes

Key Differences

• blue whale is Vulnerable while Common Red-legged Robberfly is Least Concern.

Taxonomic Classification

Rank	blue whale	Common Red-legged Robberfly
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Chordata (Chordates)	Arthropoda (Arthropods)
Class	Mammalia (Mammals)	Insecta (Insects)
Order	Cetacea (Whales & Dolphins)	Diptera (Diptera)
Family	Balaenopteridae (Rorquals)	Asilidae
Genus	Balaenoptera (Rorquals)	Dioctria
Species	Balaenoptera musculus	Dioctria rufipes

Evolutionary Relationship

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

Conservation Status

blue whale

VU — Vulnerable

Population: ~15.0K

Trend: Increasing ↑

Common Red-legged Robberfly

LC — Least Concern

Physical Characteristics

Attribute	blue whale	Common Red-legged Robberfly
Diet	Carnivore	—
Average Lifespan	90 years	—
Average Length	30.0 m	—
Average Weight	150.0 t	—

Habitat & Geographic Range

blue whale

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and tropical and subtropical grasslands and savannas, among 11 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (Taiwan), Europe (4 countries), and South America (Colombia, Ecuador). Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Common Red-legged Robberfly

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

blue whale

The largest animal ever known to have lived on Earth, blue whales can reach 33 meters and 200 tonnes — their hearts alone weigh as much as a small car. Found in all oceans, they migrate between polar feeding grounds and tropical breeding areas. Filter feeders consuming up to 4 tonnes of krill daily. Endangered, with global populations estimated at 10,000–25,000 after near-extinction from 20th-century whaling.

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