Did you know that only 10 out of over 465 shark species regularly reach a length of over 13 feet -4 metres-? Most sharks are much smaller than us, and the Dwarf lanternshark is said to be the smallest of all.

Etmopterus perryi / Dwarf lanternshark, image source: Etmopteridae: Lanternsharks

It lives at the Caribbean coast off Colombia and Venezuela in the deep sea. Like its near relative, the velvet belly lanternshark, the dwarf lanternshark has got large eyes, defensive spines in front of its dorsal fins and uses bioluminescence to counterilluminate (and causes its color to appear blue instead of brown). Additional to light-producing photophores, the skin of dwarf lanternsharks contains also pigment-containing chromatophores.

Like all lanternshark it is ovoviviparous, which is used to determine its status as smallest shark. Obviously, only the length of adult sharks should be factored in, but how do you determine whether a shark is mature or not? Female sharks are regularly larger than males to secure the survival of the young and thus the species, therefore the length of mature female sharks, proved by its gravidity, could be a valid criteria.

Since one 7.5 in -19 cm- long specimen of Etmopterus perryi was found containing three 2.4 in -6 cm- long embryos (no mean feat in itself), it makes the dwarf lanternshark the World’s Smallest Living Shark, at least up to 1999.

Source: here and here