Japanese Spider Crab
The Japanese spider crab, Macrocheira kaempferi, is the largest known arthropod living at present time; fully grown it can reach a leg span of almost 4 m (13 ft), a body size of up to 37 cm (15 inches) and a weight of up to 20 kg (44 lb). The crab's natural habitat is on the bottom of the Pacific Ocean (some 300 to 400 m deep) around Japan, where it feeds on dead animals and shellfish. It is believed to have a life expectancy of up to 100 years. Because it is a particularly old species of crab, it is often referred to as a living fossil. Currently, this is the only species of the genus Macrocheira, but there have been two reports of other fossil specimens. M. kaempferi is named in honor of Engelbert Kaempfer, the Japan traveller and naturalist from Lemgo, Germany.