Arthropoda · arthropods

Yeti crab

Kiwa hirsuta

Kiwaidae · yeti crabsIUCN: Not evaluated
Yeti crab
Photo: Andrew Thurber, Oregon State University · CC BY-SA 2.0 · Wikimedia Commons · resized

A blind, white crab with hairy arms, found at deep-sea vents.

Fun factBacteria grow on the hairs of its arms, and studies suggest these bacteria are its main food.

Waters
South Pacific
Depth zone
Hydrothermal vents
Diet
Bacteria grown on its own setae
Size
About 15 cm

Classification

Arthropoda › Malacostraca › Decapoda › Kiwaidae

  1. Kingdom Animalia animals
    • Many-celled organisms that eat other living things for energy (heterotrophs)
    • Cells have no cell walls
    • Most can move at some stage of life
  2. Clade Bilateria bilateral animals
    • Body has a left and right side that mirror each other (bilateral symmetry)
    • Head end with concentrated nerves; three tissue layers
    • Includes about 99% of all living animal species
  3. Clade Protostomia protostomes
    • In the embryo, the first opening usually becomes the mouth
    • Main nerve cord runs along the belly (ventral)
    • Includes mollusks, worms, and arthropods
  4. Clade Ecdysozoa molting animals
    • Grow by shedding their outer layer (molting, ecdysis)
    • No cilia used for movement
    • Includes arthropods and nematode worms
  5. Phylum Arthropoda arthropods
    • Hard outer skeleton made of chitin (exoskeleton)
    • Jointed legs and a segmented body
    • The largest animal phylum by species count
  6. Subphylum Crustacea crustaceans
    • Two pairs of antennae
    • Branched (biramous) legs in many species
    • Most breathe with gills
  7. Class Malacostraca crabs, shrimp & kin
    • Body of a head, 8-segment thorax, and 6-segment abdomen
    • Includes crabs, shrimp, lobsters, krill, and isopods
  8. Order Decapoda ten-legged crustaceans
    • Ten walking legs, the first pair often with claws
    • Shell covers head and thorax together (carapace)
  9. Suborder Pleocyemata egg-brooding decapods
    • Females carry their eggs under the abdomen until they hatch
    • Includes true crabs, lobsters, and most shrimp
  10. Infraorder Anomura hermit & king crabs
    • Last pair of walking legs is small and often hidden
    • Includes hermit crabs, king crabs, and mole crabs
  11. Family Kiwaidae yeti crabs
    • Yeti crabs: hairy-armed crabs of deep-sea vents and seeps
  12. Genus Kiwa
    • Species in the same genus are very close relatives and often look alike.
  13. Species Kiwa hirsuta Yeti crab

Closest relatives in the guide