Squaliolus laticaudus

Order: Squaliformes

Long thought to be the smallest species of shark, the spined pygmy shark’s claim to fame has recently been challenged by the discovery of the dwarf lantern shark, to which it is closely related. Nonetheless, it is still remarkable; at a maximum length of about 20 centimetres, it is far from the popular image of a shark as a large, ocean-going predator.

As a member of the Squaliformes order, it is part of a group of sharks defined by extremes; the predatory Greenland shark, a close relative, is almost the equal of the great white in terms of size, if not ferocity. Another relative, the Portuguese shark, holds the record for the greatest depth at which sharks have been found – some specimens have been captured at depths of over 3,000 metres.

The spined pygmy shark is a deepwater species, and is one of the very few sharks to exhibit bioluminescence – its belly glows in the dark, perhaps to attract the small creatures on which it feeds.

Maximum size: About 20cm.

Distribution: Temperate and tropical oceans worldwide, in very deep water – perhaps as deep as 2,000 metres.

Diet: Small shrimps, squid and deepwater fishes.

Reproduction: Uncertain.