HomeFish encyclopediaSharks and RaysBramble, Sleeper and Dogfish sharksSleeper sharksSmalleye pygmy shark Smalleye pygmy shark (Squaliolus aliae) Scientific name: Squaliolus aliae Teng, 1959 The Smalleye pygmy shark (Squaliolus aliae) is a marine fish of the family Dalatiidae. Native range: Western Pacific, Japan to Australia (off northwestern Australia and New South Wales). BiologyPossibly the smallest living shark. Found near continental and island land masses. Feeds mainly on cephalopods and small midwater bony fishes. Probably makes diurnal vertical migrations from within 200 m of the surface at night down to about 2,000 m during the day. Ovoviviparous.Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameSqualiolus aliaeFamilyDalatiidae (Sleeper sharks)OrderSqualiformes (Bramble, Sleeper and Dogfish sharks)ClassElasmobranchii (Sharks and Rays)Maximum length22.0Depth range200–2000 m (656–6562 ft)EnvironmentMarine; bathypelagic; depth range 200 - 2000 mClimateDeep-waterDistributionWestern Pacific: Japan to Australia (off northwestern Australia and New South Wales).Conservation status (IUCN)Least Concern (LC)Threat to humansHarmlessUsesFisheries: of no interestResilienceLow, minimum population doubling time 4.5 - 14 years (Fec assumed to be SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.Last updated 27 September 2026