Cigar shark vs Commerson's Leaf-nosed Bat

Isistius brasiliensis compared with Macronycteris commersonii

Key Differences

• Cigar shark is Least Concern while Commerson's Leaf-nosed Bat is Near Threatened.

Taxonomic Classification

Rank	Cigar shark	Commerson's Leaf-nosed Bat
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Elasmobranchii	Mammalia (Mammals)
Order	Squaliformes (Squaliformes)	Chiroptera (Bats)
Family	Dalatiidae	Hipposideridae
Genus	Isistius	Macronycteris
Species	Isistius brasiliensis	Macronycteris commersonii

Evolutionary Relationship

Cigar shark and Commerson's Leaf-nosed Bat share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

Cigar shark

LC — Least Concern

Commerson's Leaf-nosed Bat

NT — Near Threatened

Physical Characteristics

Attribute	Cigar shark	Commerson's Leaf-nosed Bat
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.

Commerson's Leaf-nosed Bat

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

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.

Commerson's Leaf-nosed Bat

<em>Macronycteris commersonii</em>, commonly known as Commerson's Leaf-nosed Bat, is a chiropteran mammal in the family Hipposideridae. This species is assessed as Near Threatened on the IUCN Red List, indicating that it faces increasing pressures that could elevate its risk of extinction without conservation attention. Commerson's Leaf-nosed Bat typically inhabits a range of diverse ecosystems across sub-Saharan Africa, including forests, savannas, and areas near caves or rocky outcrops that serve as roosting sites. Like other hipposiderid bats, it uses echolocation to navigate and hunt in low-light conditions, often foraging for insects in open or semi-open environments after dark. Roost disturbance, habitat degradation, and human persecution are among the primary threats facing this species. The large, elaborately shaped noseleaf characteristic of the family helps focus echolocation signals during foraging. Populations are typically found roosting in caves, mines, and hollow trees in groups that may range from small colonies to large aggregations. Biological traits of this species remain poorly documented in the scientific literature.