The first species of Yeti
Crab1 from hydrothermal
vent2 systems of the East Scotia
Ridge3 in the Southern Ocean, Antarctica, has been described by a team of British scientists. The species Kiwa tyleri is named after world-renowned British deep-sea and polar biologist Professor Paul Tyler from the University of Southampton.
Kiwa tyleri belongs to an enigmatic group of
squat4 lobsters5, known as Kiwaidae, that thrive in the hot waters surrounding the geothermally heated hydrothermal
vents6. It is the
dominant7 species at these sites occurring at extremely high
densities8, exceeding 700
specimens9 per square metre.
This Yeti Crab is famous for its body, which is
densely11 covered by
bristles12 - known as setae - and bacteria, giving it a fur-like appearance. Kiwa tyleri's appearance allows it to harvest the
dense10 bacterial13 mats, which overgrow the surfaces of vent chimneys, on which it depends on for food from the chemosynthetic bacteria.
For most of its life, Kiwa tyleri is trapped within the warm water environment of the vent chimney (up to about 25 degrees Celsius) and is unable move between vent sites because of the hostile, low temperature (about zero degrees Celsius), polar environment in between. Females carrying eggs only move away from vent chimneys, and into the surrounding polar deep-sea, in order to release their
larvae14; these would otherwise not survive the warmer temperatures of the adult habitat.
Crabs15 and lobsters, which are a characteristic of the global oceans, show an extremely low species number in polar seas. Hydrothermal vent systems found in the Southern Ocean, therefore, present a unique warm-water refuge to Yeti Crabs.