Elasmobranchii (sharks and rays) > Squaliformes
(Sleeper and dogfish sharks) > Dalatiidae
Etymology: Squaliolus: Latin, squalidus = pale, weak (Ref. 45335); aliae: Named for the wife of the describer (specific name corrected to aliae by Sasaki and Uyeno, Ref. 47737).
Environment: milieu / climate zone / depth range / distribution range
Marine; bathypelagic; depth range 200 - 2000 m (Ref. 6871), usually - m (Ref. ). Deep-water; 0°C -
Western Pacific: Japan to Australia (off northwestern Australia and New South Wales).
Length at first maturity / Size / Weight / Age
Maturity: Lm ?, range 15 - ? cm
Max length : 22.0 cm TL male/unsexed; (Ref. 6871)
soft rays: 0. The smalleye pygmy shark, Squaliolus aliae, is a very small dogfish (about 22cm) characterized by its small eye, with diameter about 46-70% of interorbital width, and with upper margin angular and chevron-shaped; upper lip with a pair of prominent lateral papillae (rarely indistinct) (Ref. 31367, 6871).Colour: dark brown to black, fin margins pale (Ref. 6871). Squaliolus are the only sharks with a fin spine on its first dorsal fin (spine sometimes concealed by skin) but not on its second dorsal fin; second dorsal fin long-based and low, about twice the length of the first dorsal fin base; first dorsal-fin base closer to pectoral fins than to pelvic fins; and caudal fin nearly symmetrical, with subterminal notch present (Ref. 247, 6871).
Possibly the smallest living shark (Ref. 6871). Found near continental and island land masses (Ref. 31367). Feeds mainly on cephalopods and small midwater bony fishes (Ref. 6871). Probably makes diurnal vertical migrations from within 200 m of the surface at night down to about 2,000 m during the day (Ref. 6871). Ovoviviparous (Ref. 6871).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Distinct pairing with embrace (Ref. 205). Ovoviviparous but litter size unknown (Ref. 6871). Males mature at 15 cm (Ref. 31367).
Last, P.R. and J.D. Stevens, 1994. Sharks and rays of Australia. CSIRO, Australia. 513 p. (Ref. 6871)
IUCN Red List Status (Ref. 124695)
Threat to humans
Fisheries: of no interest
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Preferred temperature (Ref. 115969
): 4.6 - 10.1, mean 6.5 °C (based on 559 cells).
Phylogenetic diversity index (Ref. 82805
= 0.7520 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00372 (0.00141 - 0.00976), b=3.12 (2.89 - 3.35), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic level (Ref. 69278
): 4.4 ±0.57 se; based on food items.
Resilience (Ref. 120179
): Low, minimum population doubling time 4.5 - 14 years (Fec assumed to be <100).
Vulnerability (Ref. 59153
): Low vulnerability (11 of 100) .