Cigar shark vs Eurasian Skylark

Isistius brasiliensis compared with Alauda arvensis

Key Differences

• Cigar shark is Least Concern while Eurasian Skylark is Vulnerable.

Taxonomic Classification

Rank	Cigar shark	Eurasian Skylark
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Elasmobranchii	Aves (Birds)
Order	Squaliformes (Squaliformes)	Passeriformes (Songbirds)
Family	Dalatiidae	Alaudidae
Genus	Isistius	Alauda
Species	Isistius brasiliensis	Alauda arvensis

Evolutionary Relationship

Cigar shark and Eurasian Skylark share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

Cigar shark

LC — Least Concern

Eurasian Skylark

VU — Vulnerable

Physical Characteristics

Attribute	Cigar shark	Eurasian Skylark
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Cigar shark

Habitat

Native to Asia and Europe and South America, inhabiting ecosystems characteristic of the region.

Range

Distributed across Chile, Norway, and Taiwan.

Eurasian Skylark

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, tundra, and tropical and subtropical moist broadleaf forests spanning the Australasia and Oceanian realms.

Range

Widely distributed across Europe (5 countries), North America (Canada, United States), and Oceania and the Pacific (Australia, New Zealand). Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Cigar shark

The cigar shark, also known as the cookiecutter shark (Isistius brasiliensis), is a small but remarkable shark in the family Dalatiidae, found throughout warm oceanic waters worldwide in tropical and subtropical latitudes. Reaching only 40–50 centimeters in length, it possesses oversized jaws with large, triangular lower teeth arranged in a saw-like series that cut distinctive circular plugs of flesh from much larger prey—including tuna, dolphins, whales, billfish, and even submarine cables and human bodies. It does not kill its prey but instead latches on, rotates its body, and excises a characteristic cookie-cutter-shaped bite. The cigar shark is bioluminescent, emitting a green glow from photophores on its ventral surface that may serve as counter-illumination or to attract prey from below. It undertakes diel vertical migrations, ascending to shallower waters at night and descending to mesopelagic depths during the day. The species is classified as Least Concern by the IUCN, with a vast oceanic distribution and no targeted commercial fishery. It is occasionally taken as bycatch. The geographic epithet brasiliensis refers to Brazil, where early specimens were described, but the species' range is circumglobal in warm oceans. The cookiecutter shark's feeding strategy is one of the most unusual among elasmobranchs.

Eurasian Skylark

Celebrated across European literature and poetry for its complex, melodious song sung on the wing during spectacular display flights, Eurasian skylarks soar vertically hundreds of meters above open farmland, grassland, and heathland across Europe and Asia while producing an uninterrupted torrent of song lasting up to an hour. Males can produce over 700 distinct song phrases. Once enormously abundant across European farmland, skylark populations have declined over 70% since 1970 due to agricultural intensification.

Shared Countries

Both species can be found in 1 countries:

🇳🇴 Norway