Kiwa (crustacean)

Kiwa
Kiwa hirsuta
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Malacostraca
Order: Decapoda
Suborder: Pleocyemata
Infraorder: Anomura
Superfamily: Chirostyloidea
Family: Kiwaidae
Macpherson, Jones & Segonzac, 2006
Genus: Kiwa
Macpherson, Jones & Segonzac, 2006

Kiwa is a genus of marine decapods living at deep-sea hydrothermal vents and cold seeps. The animals are commonly referred to as "yeti lobsters" or "yeti crabs”, after the legendary yeti, because of their "hairy" or bristly appearance.[1] The genus is placed in its own family, Kiwaidae, in the superfamily Chirostyloidea.[2] The genus Kiwa is named after the god of shellfish in Polynesian mythology.[1]

Population of Kiwa around a hydrothermal vent

Based on the presence of sulphur-oxidising bacteria on the setae of both K. hirsuta and the new South West Indian Ridge species, they may both feed on bacteria in addition to scavenging.[3] For K. puravida, the bacteria have been identified and the feeding behaviour observed, as well as a cyclical rhythmic motion of the crab documented that is suspected to increase the flow of methane and hydrogen sulfide, the bacterial food, towards the bacteria.[4] The two sexes of the new South West Indian Ridge species prefer different temperatures, with males seeming to prefer warmer water and egg-carrying females and juveniles preferring the coldest.[3] Chemosynthetic bacteria is growing which is affecting the habitat for yeti crabs.

Because yeti crabs live in extreme environments like cold seeps and hydrothermal vents, the species has adapted certain behaviors and qualities to aid their survival. These adaptations include the crab's growth of their setae,[5] propodus[6] and claws.[7] The internal anatomy, diet, behaviors and adaptations of the yeti crab are outlined below.

  1. ^ a b Macpherson E, Jones W, Segonzac M (2006). "A new squat lobster family of Galatheoidea (Crustacea, Decapoda, Anomura) from the hydrothermal vents of the Pacific-Antarctic Ridge" (PDF). Zoosystema. 27 (4): 709–723.
  2. ^ Schnabel KE, Ahyong ST, Maas EW (February 2011). "Galatheoidea are not monophyletic - molecular and morphological phylogeny of the squat lobsters (Decapoda: Anomura) with recognition of a new superfamily". Molecular Phylogenetics and Evolution. 58 (2): 157–68. Bibcode:2011MolPE..58..157S. doi:10.1016/j.ympev.2010.11.011. PMID 21095236.
  3. ^ a b Rogers AD, Tyler PA, Connelly DP, Copley JT, James R, Larter RD, et al. (January 2012). "The discovery of new deep-sea hydrothermal vent communities in the southern ocean and implications for biogeography". PLOS Biology. 10 (1): e1001234. doi:10.1371/journal.pbio.1001234. PMC 3250512. PMID 22235194.
  4. ^ Thurber AR, Jones WJ, Schnabel K (2011). "Dancing for food in the deep sea: bacterial farming by a new species of Yeti crab". PLOS ONE. 6 (11): e26243. Bibcode:2011PLoSO...626243T. doi:10.1371/journal.pone.0026243. PMC 3227565. PMID 22140426.
  5. ^ Thurber AR, Jones WJ, Schnabel K (2011). "Dancing for food in the deep sea: bacterial farming by a new species of Yeti crab". PLOS ONE. 6 (11): e26243. Bibcode:2011PLoSO...626243T. doi:10.1371/journal.pone.0026243. PMC 3227565. PMID 22140426.
  6. ^ Thatje S, Marsh L, Roterman CN, Mavrogordato MN, Linse K (2015-06-24). "Adaptations to Hydrothermal Vent Life in Kiwa tyleri, a New Species of Yeti Crab from the East Scotia Ridge, Antarctica". PLOS ONE. 10 (6): e0127621. Bibcode:2015PLoSO..1027621T. doi:10.1371/journal.pone.0127621. ISSN 1932-6203. PMC 4480985. PMID 26107940.
  7. ^ Azofeifa-Solano JC, Pereira OS, Cowell EJ, Cordes EE, Levin LA, Goffredi SK, et al. (2022). "Sexual dimorphism in the methane seep-dwelling Costa Rican yeti crab Kiwa puravida (Decapoda: Anomura: Kiwaidae)". Frontiers in Marine Science. 9. doi:10.3389/fmars.2022.1051590. hdl:20.500.12613/10019. ISSN 2296-7745.