Biology:Crab

From HandWiki
Revision as of 06:21, 13 February 2024 by Scavis (talk | contribs) (simplify)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Short description: Infraorder of decapod crustaceans

Crab
Temporal range: Early Jurassic–Present
Brachyura montage.jpg
Top row, left to right: Dromia personata (Dromiidae), Dungeness crab (Cancridae), Tasmanian giant crab (Menippidae); Middle row: Corystes cassivelaunus (Corystidae), Liocarcinus vernalis (Portunidae), Carpilius maculatus (Carpiliidae); Bottom row: Gecarcinus quadratus (Gecarcinidae), Grapsus grapsus (Grapsidae), Ocypode ceratophthalmus (Ocypodidae).
Scientific classification e
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Malacostraca
Order: Decapoda
Suborder: Pleocyemata
(unranked): Reptantia
Infraorder: Brachyura
Linnaeus, 1758
Sections and subsections[1]

Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen), usually hidden entirely under the thorax (brachyura means "short tail" in Greek).[lower-alpha 1] They live in all the world's oceans, in freshwater, and on land, are generally covered with a thick exoskeleton, and have a single pair of pincers on each arm. They first appeared during the Jurassic Period.

Description

Gecarcinus quadratus, a land crab from Central America

Crabs are generally covered with a thick exoskeleton, composed primarily of highly mineralized chitin.[4][5] Behind their pair of chelae (claws) are six walking legs and then two swimming legs. The crab breathes through gills on its underside; gills must be at least moist to work.

Crabs vary in size from the pea crab, a few millimeters wide, to the Japanese spider crab, with a leg span up to 4 m (13 ft).[6] Several other groups of crustaceans with similar appearances – such as king crabs and porcelain crabs – are not true crabs, but have evolved features similar to true crabs through a process known as carcinisation.[7][8][9][10]

Environment

Crabs are found in all of the world's oceans, as well as in fresh water and on land, particularly in tropical regions. About 850 species are freshwater crabs.[11]

Sexual dimorphism

The underside of a male (top) and a female (bottom) individual of Pachygrapsus marmoratus, showing the difference in shape of the abdomen

Crabs often show marked sexual dimorphism. Males often have larger claws,[12] a tendency that is particularly pronounced in the fiddler crabs of the genus Uca (Ocypodidae). In fiddler crabs, males have one greatly enlarged claw used for communication, particularly for attracting a mate.[13] Another conspicuous difference is the form of the pleon (abdomen); in most male crabs, this is narrow and triangular in form, while females have a broader, rounded abdomen.[14] This is because female crabs brood fertilised eggs on their pleopods.

Reproduction and life cycle

Crab (Pachygrapsus marmoratus) on Istrian coast, Adriatic Sea

Crabs attract a mate through chemical (pheromones), visual, acoustic, or vibratory means. Pheromones are used by most fully aquatic crabs, while terrestrial and semiterrestrial crabs often use visual signals, such as fiddler crab males waving their large claws to attract females. The vast number of brachyuran crabs have internal fertilisation and mate belly-to-belly. For many aquatic species, mating takes place just after the female has moulted and is still soft. Females can store the sperm for a long time before using it to fertilise their eggs. When fertilisation has taken place, the eggs are released onto the female's abdomen, below the tail flap, secured with a sticky material. In this location, they are protected during embryonic development. Females carrying eggs are called "berried" since the eggs resemble round berries.

When development is complete, the female releases the newly hatched larvae into the water, where they are part of the plankton. The release is often timed with the tidal and light/dark diurnal cycle.[15][16] The free-swimming tiny zoea larvae can float and take advantage of water currents. They have a spine, which probably reduces the rate of predation by larger animals. The zoea of most species must find food, but some crabs provide enough yolk in the eggs that the larval stages can continue to live off the yolk.

Female crab Xantho poressa at spawning time in the Black Sea, carrying eggs under her abdomen

File:Grapsus tenuicrustatus - hawaii - 2015-11-01.webm

Each species has a particular number of zoeal stages, separated by moults, before they change into a megalopa stage, which resembles an adult crab, except for having the abdomen (tail) sticking out behind. After one more moult, the crab is a juvenile, living on the bottom rather than floating in the water. This last moult, from megalopa to juvenile, is critical, and it must take place in a habitat that is suitable for the juvenile to survive.[17]:63–77

Most species of terrestrial crabs must migrate down to the ocean to release their larvae; in some cases, this entails very extensive migrations. After living for a short time as larvae in the ocean, the juveniles must do this migration in reverse. In many tropical areas with land crabs, these migrations often result in considerable roadkill of migrating crabs.[17]:113–114

Once crabs have become juveniles, they still have to keep moulting many more times to become adults. They are covered with a hard shell, which would otherwise prevent growth. The moult cycle is coordinated by hormones. When preparing for moult, the old shell is softened and partly eroded away, while the rudimentary beginnings of a new shell form under it. At the time of moulting, the crab takes in a lot of water to expand and crack open the old shell at a line of weakness along the back edge of the carapace. The crab must then extract all of itself – including its legs, mouthparts, eyestalks, and even the lining of the front and back of the digestive tract – from the old shell. This is a difficult process that takes many hours, and if a crab gets stuck, it will die. After freeing itself from the old shell (now called an exuvia), the crab is extremely soft and hides until its new shell has hardened. While the new shell is still soft, the crab can expand it to make room for future growth.[17]:78–79

Behaviour

Carpilius convexus consuming Heterocentrotus trigonarius in Hawaii

Crabs typically walk sideways[18] (hence the term crabwise), because of the articulation of the legs which makes a sidelong gait more efficient.[19] Some crabs walk forward or backward, including raninids,[20] Libinia emarginata[21] and Mictyris platycheles.[18] Some crabs, like the Portunidae and Matutidae, are also capable of swimming,[22] the Portunidae especially so as their last pair of walking legs are flattened into swimming paddles.[17]:96

Crabs are mostly active animals with complex behaviour patterns such as communicating by drumming or waving their pincers. Crabs tend to be aggressive toward one another, and males often fight to gain access to females.[23] On rocky seashores, where nearly all caves and crevices are occupied, crabs may also fight over hiding holes.[24] Fiddler crabs (genus Uca) dig burrows in sand or mud, which they use for resting, hiding, and mating, and to defend against intruders.[17]:28–29, 99

Crabs are omnivores, feeding primarily on algae,[25] and taking any other food, including molluscs, worms, other crustaceans, fungi, bacteria, and detritus, depending on their availability and the crab species. For many crabs, a mixed diet of plant and animal matter results in the fastest growth and greatest fitness.[26][27] Some species are more specialised in their diets, based in plankton, clams or fish.[17]:85

Crabs are known to work together to provide food and protection for their family, and during mating season to find a comfortable spot for the female to release her eggs.[28]

Human consumption

Fisheries

File:The Lobster Pot - a shellfish company from Wales - 2016.webm

Main page: Biology:Crab fisheries

Crabs make up 20% of all marine crustaceans caught, farmed, and consumed worldwide, amounting to 1.5 million tonnes annually. One species, Portunus trituberculatus, accounts for one-fifth of that total. Other commercially important taxa include Portunus pelagicus, several species in the genus Chionoecetes, the blue crab (Callinectes sapidus), Charybdis spp., Cancer pagurus, the Dungeness crab (Metacarcinus magister), and Scylla serrata, each of which yields more than 20,000 tonnes annually.[29]

In some crab species, meat is harvested by manually twisting and pulling off one or both claws and returning the live crab to the water in the knowledge that the crab may survive and regenerate the claws.[30][31][32]

Cookery

Photo of cooked crab in bowl of soup
Crab masala from Karnataka, India

Crabs are prepared and eaten as a dish in many different ways all over the world. Some species are eaten whole, including the shell, such as soft-shell crab; with other species, just the claws or legs are eaten. The latter is particularly common for larger crabs, such as the snow crab. In many cultures, the roe of the female crab is also eaten, which usually appears orange or yellow in fertile crabs. This is popular in Southeast Asian cultures, some Mediterranean and Northern European cultures, and on the East, Chesapeake, and Gulf Coasts of the United States.

In some regions, spices improve the culinary experience. In Southeast Asia and the Indosphere, masala crab and chilli crab are examples of heavily spiced dishes. In the Chesapeake Bay region, blue crab is often steamed with Old Bay Seasoning. Alaskan king crab or snow crab legs are usually simply boiled and served with garlic or lemon butter.

For the British dish dressed crab, the crab meat is extracted and placed inside the hard shell. One American way to prepare crab meat is by extracting it and adding varying amounts of binders, such as egg white, cracker meal, mayonnaise, or mustard, creating a crab cake. Crabs can also be made into a bisque, a global dish of French origin which in its authentic form includes in the broth the pulverized shells of the shellfish from which it is made.

Imitation crab, also called surimi, is made from minced fish meat that is crafted and colored to resemble crab meat. While it is sometimes disdained among some elements of the culinary industry as an unacceptably low-quality substitute for real crab, this does not hinder its popularity, especially as a sushi ingredient in Japan and South Korea, and in home cooking, where cost is often a chief concern.[33] Indeed, surimi is an important source of protein in most East and Southeast Asian cultures, appearing in staple ingredients such as fish balls and fish cake.

Pain

Whether crustaceans as a whole experience pain or not is a scientific debate that has ethical implications for crab dish preparation. Crabs are very often boiled alive as part of the cooking process.

This section is an excerpt from Pain in crustaceans § Opinions[ edit ]

Evolution

Reconstruction of Eocarcinus, the earliest known crab

The earliest unambiguous crab fossils date from the Early Jurassic, with the oldest being Eocarcinus from the early Pliensbachian of Britain, which likely represents a stem-group lineage, as it lacks several key morphological features that define modern crabs.[34][35] Most Jurassic crabs are only known from dorsal (top half of the body) carapaces, making it difficult to determine their relationships.[36] Crabs radiated in the Late Jurassic, corresponding with an increase in reef habitats, though they would decline at the end of the Jurassic as the result of the decline of reef ecosystems. Crabs increased in diversity through the Cretaceous and represented the dominant group of decapods by the end of the period.[37]

The crab infraorder Brachyura belongs to the group Reptantia, which consists of the walking/crawling decapods (lobsters and crabs). Brachyura is the sister clade to the infraorder Anomura, which contains the hermit crabs and relatives. The cladogram below shows Brachyura's placement within the larger order Decapoda, from analysis by Wolfe et al., 2019.[38]

Decapoda
 

Dendrobranchiata (prawns) Litopenaeus setiferus.png

 
Pleocyemata
 
 

Stenopodidea (boxer shrimp) Spongicola venustus.png

 
 
 

Procarididea

 
 

Caridea (true shrimp) Macrobrachium sp.jpg

 
 
 
Reptantia
 
 

Achelata (spiny lobsters, slipper lobsters) Panulirus argus.png

 
 
 

Polychelida (benthic crustaceans)

 
 

Astacidea (lobsters, crayfish) Lobster NSRW rotated2.jpg

 
 
 
 
 

Axiidea (mud shrimp, ghost shrimp, or burrowing shrimp)

 
 
 

Gebiidea (mud lobsters and mud shrimp)

 
Meiura
 

Anomura (hermit crabs and others) Coenobita variabilis.jpg

 
 

Brachyura (crabs) Charybdis japonica.jpg

 
 
 
 
(crawling/walking decapods)
 
 

Brachyura is separated into several sections, with the basal Dromiacea diverging the earliest in the evolutionary history, around the Late Triassic or Early Jurassic. The group consisting of Raninoida and Cyclodorippoida split off next, during the Jurassic period. The remaining clade Eubrachyura then divided during the Cretaceous period into Heterotremata and Thoracotremata. A summary of the high-level internal relationships within Brachyura can be shown in the cladogram below: [39] [38]

Brachyura
 

Dromiacea

 
 
 
 

Raninoida

 
 

Cyclodorippoida

 
 
Eubrachyura
 

Heterotremata

 
 

Thoracotremata

 
 
 
 

There is a no consensus on the relationships of the subsequent superfamilies and families. The proposed cladogram below is from analysis by Tsang et al, 2014:[39]

Brachyura
Dromiacea
Dromioidea
 

Dromiidae (may be paraphyletic)

 
 

Dynomenidae

 
 
Homoloidea
 

Homolidae (paraphyletic)

 
 

Latreilliidae

 
 
 
 
 
Raninoida

Raninidae

 
Cyclodorippoida
 

Cyclodorippidae

 
 

Cymonomidae

 
 
 
Eubrachyura
Heterotremata
Freshwater crabs
Potamoidea
 

Potamonautidae

 
 
 

Potamidae

 
 

Gecarcinucidae

 
 
(Old World freshwater crabs)
Pseudothelphusoidea

Pseudothelphusidae

(New World freshwater crabs)
 
 

 

 
 
 
 
 

Trichodactylidae (freshwater crabs)

 
 

Orithyiidae

 
 
 
 
 

Belliidae

 
 

Chasmocarcinidae

 
 
 

Retroplumidae

 
 
 
 
 
 
Dorippoidea
 

Ethusidae

 
 

Dorippidae

 
 
 

Leucosiidae

 
 
 
Majoidea
 

Inachidae

 
 
 

Epialtidae (paraphyletic)

 
 

Majidae / Mithracidae

 
 
 
 

Corystidae

 
 
 
 
 
 

Euryplacidae

 
 

Matutidae

 
 
 
 
 
 

Calappidae

 
 
 
 

Parthenopidae

 
 

Cancridae

 
 
 
 

Carpiliidae

 
 
 

Aethridae

 
 

Pseudocarcinus of Menippidae

 
 
 
 
 
 
 

Menippe of Menippidae

 
 
 

Polybiidae

 
 

Portunidae

 
 
 
 
 
Pilumnoidea
 

Tanaochelidae

 
 
 

Galenidae

 
 

Pilumnidae

 
 
 
 
 
 
 

Mathildellidae

 
 
 

Eriphiidae

 
 
 

Oziidae

 
 

Vultocinidae

 
 
 
 
 

Trapeziidae

 
 
 
 

Goneplacidae

 
 
 

Scalopidiidae

 
Xanthoidea
 

Xanthidae (paraphyletic)

 
 

Panopeidae

 
 
 
 
 
 
 
 
 
 
 
Thoracotremata
 
 

Pinnotheridae

 
 

Dotillidae

 
 
 
 

Percnidae

 
 
 
 

Xenograpsidae

 
 

Cryptochiridae

 
 
 
 
 

Ocypodidae

 
 
 

Glyptograpsidae

 
 

Grapsidae

 
 
 
 
 
 
 

Plagusiidae

 
 

Gecarcinidae

 
 
 

Sesarmidae

 
 
 
 

Mictyridae

 
 
 

Varunidae

 
 

Macrophthalmidae

 
 
 
 
 
 
 
 
 
 
 

Classification

The infraorder Brachyura contains approximately 7,000 species in 98 families,[39][22] as many as the remainder of the Decapoda.[40] The evolution of crabs is characterised by an increasingly robust body, and a reduction in the abdomen. Although many other groups have undergone similar processes, carcinisation is most advanced in crabs. The telson is no longer functional in crabs, and the uropods are absent, having probably evolved into small devices for holding the reduced abdomen tight against the sternum.

In most decapods, the gonopores (sexual openings) are found on the legs. Since crabs use their first two pairs of pleopods (abdominal appendages) for sperm transfer, this arrangement has changed. As the male abdomen evolved into a slimmer shape, the gonopores have moved toward the midline, away from the legs, and onto the sternum.[41] A similar change occurred, independently, with the female gonopores. The movement of the female gonopore to the sternum defines the clade Eubrachyura, and the later change in the position of the male gonopore defines the Thoracotremata. It is still a subject of debate whether a monophyletic group is formed by those crabs where the female, but not male, gonopores are situated on the sternum.[40]

Superfamilies

Numbers of extant and extinct (†) species are given in brackets.[1] The superfamily Eocarcinoidea, containing Eocarcinus and Platykotta, was formerly thought to contain the oldest crabs; it is now considered part of the Anomura.[42]

Examples of different crab sections
Dromia personata (Dromiacea: Dromiidae)
Ranina ranina (Raninoida: Raninidae)
Corystes cassivelaunus (Heterotremata: Corystidae)
Ocypode quadrata (Thoracotremata: Ocypodidae)
Goneplax rhomboides

Recent studies have found the following superfamilies and families to not be monophyletic, but rather paraphyletic or polyphyletic:[39][38][45][44]

Cultural influences

A crab divination pot in Kapsiki, North Cameroon.

Both the constellation Cancer and the astrological sign Cancer are named after the crab, and depicted as a crab. William Parsons, 3rd Earl of Rosse drew the Crab Nebula in 1848 and noticed its similarity to the animal; the Crab Pulsar lies at the centre of the nebula.[46] The Moche people of ancient Peru worshipped nature, especially the sea,[47] and often depicted crabs in their art.[48] In Greek mythology, Karkinos was a crab that came to the aid of the Lernaean Hydra as it battled Heracles. One of Rudyard Kipling's Just So Stories, The Crab that Played with the Sea, tells the story of a gigantic crab who made the waters of the sea go up and down, like the tides.[49] The auction for the crab quota in 2019, Russia is the largest revenue auction in the world except the spectrum auctions. In Malay mythology (as related by Hugh Clifford to Walter William Skeat), ocean tides are believed to be caused by water rushing in and out of a hole in the Navel of the Seas (Pusat Tasek), where "there sits a gigantic crab which twice a day gets out in order to search for food".[50]:7–8

The Kapsiki people of North Cameroon use the way crabs handle objects for divination.[citation needed]

The term crab mentality is derived from a type of detrimental social behavior observed in crabs.

Explanatory notes

  1. ↑ Greek: βραχύς, romanized: brachys = short,[2] οὐρά / οura = tail[3]

References

  1. ↑ 1.0 1.1 De Grave, Sammy et al. (2009-09-15). "A Classification of Living and Fossil Genera of Decapod Crustaceans". Raffles Bulletin of Zoology Suppl. 21: 1–109. http://rmbr.nus.edu.sg/rbz/biblio/s21/s21rbz1-109.pdf. Retrieved 2024-01-03. 
  2. ↑ "βραχύς". A Greek–English Lexicon. Perseus Digital Library. https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3Dbraxu%2Fs. 
  3. ↑ "οὐρά". A Greek–English Lexicon. Perseus Digital Library. https://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3Dou%29ra%2F. 
  4. ↑ F. Boßelmann; P. Romano; H. Fabritius; D. Raabe; M. Epple (October 25, 2007). "The composition of the exoskeleton of two crustacea: The American lobster Homarus americanus and the edible crab Cancer pagurus". Thermochimica Acta 463 (1–2): 65–68. doi:10.1016/j.tca.2007.07.018. 
  5. ↑ P. Chen; A.Y. Lin; J. McKittrick; M.A. Meyers (May 2008). "Structure and mechanical properties of crab exoskeletons". Acta Biomaterialia 4 (3): 587–596. doi:10.1016/j.actbio.2007.12.010. PMID 18299257. 
  6. ↑ "Japanese spider crab Macrocheira kaempferi". Oceana North America. http://na.oceana.org/en/explore/creatures/japanese-spider-crab. 
  7. ↑ Borradaile LA (1916). "Crustacea. Part II. Porcellanopagurus: an instance of carcinization". British Antarctic ("Terra Nova") Expedition, 1910. Natural History Report. Zoology 3 (3): 111–126. 
  8. ↑ Martin JW; Abele LG (1986). "Phylogenetic relationships of the genus Aegla (Decapoda: Anomura: Aeglidae), with comments on anomuran phylogeny". Journal of Crustacean Biology 6 (3): 576–612. doi:10.1163/193724086X00406. 
  9. ↑ McLaughlin PA; Lemaitre R (1997). "Carcinization in the Anomura - fact or fiction? I. Evidence from adult morphology". Contributions to Zoology 67 (2): 79–123. doi:10.1163/18759866-06702001. 
  10. ↑ Scholtz G (2014). "Evolution of crabs - history and deconstruction of a prime example of convergence". Contributions to Zoology 83 (2): 87–105. doi:10.1163/18759866-08302001. 
  11. ↑ Richard von Sternberg; Neil Cumberlidge (2001). "On the heterotreme-thoracotreme distinction in the Eubrachyura De Saint Laurent, 1980 (Decapoda: Brachyura)". Crustaceana 74 (4): 321–338. doi:10.1163/156854001300104417. http://decapoda.nhm.org/pdfs/11802/11802.pdf. 
  12. ↑ L. H. Sweat (August 21, 2009). "Pachygrapsus transversus". Smithsonian Institution. http://www.sms.si.edu/irLspec/Pachyg_transv.htm. 
  13. ↑ Martin J. How; Jan M. Hemmi; Jochen Zeil; Richard Peters (2008). "Claw waving display changes with receiver distance in fiddler crabs, Uca perplexa". Animal Behaviour 75 (3): 1015–1022. doi:10.1016/j.anbehav.2007.09.004. http://richard.eriophora.com.au/pubs/pdf/HowHemmiZeilPeters-07.pdf. 
  14. ↑ Guillermo Guerao; Guiomar Rotllant (2009). "Post-larval development and sexual dimorphism of the spider crab Maja brachydactyla (Brachyura: Majidae)". Scientia Marina 73 (4): 797–808. doi:10.3989/scimar.2009.73n4797. http://digital.csic.es/bitstream/10261/19120/3/1148.pdf. 
  15. ↑ Forward, Jr., Richard B. (1987-09-01). "Larval Release Rhythms of Decapod Crustaceans: An Overview". Bulletin of Marine Science 41 (2): 165–176. https://www.ingentaconnect.com/content/umrsmas/bullmar/1987/00000041/00000002/art00006. 
  16. ↑ Ricardo, Gerard F.; Davis, Andrew R.; Knott, Nathan A.; Minchinton, Todd E. (2014-04-01). "Diel and tidal cycles regulate larval dynamics in salt marshes and mangrove forests" (in en). Marine Biology 161 (4): 769–784. doi:10.1007/s00227-013-2376-4. ISSN 1432-1793. Bibcode: 2014MarBi.161..769R. https://doi.org/10.1007/s00227-013-2376-4. 
  17. ↑ 17.0 17.1 17.2 17.3 17.4 17.5 Judith S. Weis (2012). Walking Sideways: The Remarkable World of Crabs. Ithaca, NY: Cornell University Press. ISBN 978-0-8014-5050-1. OCLC 794640315. 
  18. ↑ 18.0 18.1 Sally Sleinis; Gerald E. Silvey (1980). "Locomotion in a forward walking crab". Journal of Comparative Physiology A 136 (4): 301–312. doi:10.1007/BF00657350. 
  19. ↑ A. G. Vidal-Gadea; M.D. Rinehart; J.H. Belanger (March 2008). "Skeletal adaptations for forward and sideways walking in three species of decapod crustaceans". Arthropod Structure & Development 37 (2): 179–194. doi:10.1016/j.asd.2007.06.002. PMID 18089130. 
  20. ↑ "Spanner crab Ranina ranina". Fishing and Aquaculture. New South Wales Department of Primary Industries. 2005. http://www.dpi.nsw.gov.au/fisheries/recreational/saltwater/sw-species/spanner-crab. 
  21. ↑ A. G. Vidal-Gadea; J. H. Belanger (2009). "Muscular anatomy of the legs of the forward walking crab, Libinia emarginata (Decapoda, Brachyura, Majoidea)". Arthropod Structure & Development 38 (3): 179–194. doi:10.1016/j.asd.2008.12.002. PMID 19166968. 
  22. ↑ 22.0 22.1 Peter K. L. Ng, Danièle Guinot & Peter J. F. Davie (2008). "Systema Brachyurorum: Part I. An annotated checklist of extant Brachyuran crabs of the world". Raffles Bulletin of Zoology 17: 1–286. http://rmbr.nus.edu.sg/rbz/biblio/s17/s17rbz.pdf. 
  23. ↑ "Crab (animal)". Encarta. Microsoft. 2005. 
  24. ↑ The Miles Kelly Book of Life. Great Bardfield, Essex: Miles Kelly Publishing. 2006. pp. 512. ISBN 978-1-84236-715-5. 
  25. ↑ Chris M. C. Woods (1993). "Natural diet of the crab Notomithrax ursus (Brachyura, Majidae) at Oaro, South Island, New Zealand". New Zealand Journal of Marine and Freshwater Research 27 (3): 309–315. doi:10.1080/00288330.1993.9516571. Bibcode: 1993NZJMF..27..309W. 
  26. ↑ Robin Kennish (1996). "Diet composition influences the fitness of the herbivorous crab Grapsus albolineatus". Oecologia 105 (1): 22–29. doi:10.1007/BF00328787. PMID 28307118. Bibcode: 1996Oecol.105...22K. 
  27. ↑ Tracy L. Buck; Greg A. Breed; Steven C. Pennings; Margo E. Chase; Martin Zimmer; Thomas H. Carefoot (2003). "Diet choice in an omnivorous salt-marsh crab: different food types, body size, and habitat complexity". Journal of Experimental Marine Biology and Ecology 292 (1): 103–116. doi:10.1016/S0022-0981(03)00146-1. 
  28. ↑ Danièle Guinot & J.–M. Bouchard (1998). "Evolution of the abdominal holding systems of brachyuran crabs (Crustacea, Decapoda, Brachyura)" (PDF). Zoosystema 20 (4): 613–694. http://www.mnhn.fr/publication/zoosyst/z98n4a4.html. 
  29. ↑ "Global Capture Production 1950–2004". Food and Agriculture Organization. http://www.fao.org/figis/servlet/TabLandArea?tb_ds=Capture&tb_mode=TABLE&tb_act=SELECT&tb_grp=COUNTRY. 
  30. ↑ "Stone Crabs FAQs". http://www.myfwc.com/research/saltwater/crustaceans-marine-arthropods/stone-crabs/faq/. 
  31. ↑ Lynsey Patterson; Jaimie T.A. Dick; Robert W. Elwood (January 2009). "Claw removal and feeding ability in the edible crab, Cancer Pagurus: implications for fishery practice". Applied Animal Behaviour Science 116 (2): 302–305. doi:10.1016/j.applanim.2008.08.007. 
  32. ↑ Queen's University, Belfast (October 10, 2007). "Declawing crabs may lead to their death". https://www.sciencedaily.com/releases/2007/10/071007210836.htm. 
  33. ↑ Daniel P. Puzo (February 14, 1985) Imitation Crab Draws Criticisms. Los Angeles Times
  34. ↑ Scholtz, Gerhard (November 2020). "Eocarcinus praecursor Withers, 1932 (Malacostraca, Decapoda, Meiura) is a stem group brachyuran" (in en). Arthropod Structure & Development 59: 100991. doi:10.1016/j.asd.2020.100991. PMID 32891896. 
  35. ↑ Carrie E. Schweitzer; Rodney M. Feldmann (2010). "The oldest Brachyura (Decapoda: Homolodromioidea: Glaessneropsoidea) known to date (Jurassic)". Journal of Crustacean Biology 30 (2): 251–256. doi:10.1651/09-3231.1. 
  36. ↑ Guinot, Danièle (2019-11-14). "New hypotheses concerning the earliest brachyurans (Crustacea, Decapoda, Brachyura)". Geodiversitas 41 (1): 747. doi:10.5252/geodiversitas2019v41a22. ISSN 1280-9659. 
  37. ↑ Klompmaker, A. A.; Schweitzer, C. E.; Feldmann, R. M.; Kowalewski, M. (2013-11-01). "The influence of reefs on the rise of Mesozoic marine crustaceans" (in en). Geology 41 (11): 1179–1182. doi:10.1130/G34768.1. ISSN 0091-7613. Bibcode: 2013Geo....41.1179K. https://pubs.geoscienceworld.org/geology/article/41/11/1179-1182/131064. 
  38. ↑ 38.0 38.1 38.2 Wolfe, Joanna M.; Breinholt, Jesse W.; Crandall, Keith A.; Lemmon, Alan R.; Lemmon, Emily Moriarty; Timm, Laura E.; Siddall, Mark E.; Bracken-Grissom, Heather D. (24 April 2019). "A phylogenomic framework, evolutionary timeline and genomic resources for comparative studies of decapod crustaceans". Proceedings of the Royal Society B 286 (1901). doi:10.1098/rspb.2019.0079. PMID 31014217. 
  39. ↑ 39.0 39.1 39.2 39.3 Ling Ming Tsang; Christoph D. Schubart; Shane T. Ahyong; Joelle C.Y. Lai; Eugene Y.C. Au; Tin-Yam Chan; Peter K.L. Ng; Ka Hou Chu (2014). "Evolutionary History of True Crabs (Crustacea: Decapoda: Brachyura) and the Origin of Freshwater Crabs". Molecular Biology and Evolution (Oxford University Press) 31 (5): 1173–1187. doi:10.1093/molbev/msu068. PMID 24520090. 
  40. ↑ 40.0 40.1 Joel W. Martin; George E. Davis (2001). An Updated Classification of the Recent Crustacea. Natural History Museum of Los Angeles County. pp. 132. http://atiniui.nhm.org/pdfs/3839/3839.pdf. Retrieved 2009-12-14. 
  41. ↑ M. de Saint Laurent (1980). "Sur la classification et la phylogénie des Crustacés Décapodes Brachyoures. II. Heterotremata et Thoracotremata Guinot, 1977". Comptes rendus de l'Académie des sciences t. 290: 1317–1320. 
  42. ↑ Jérôme Chablais; Rodney M. Feldmann; Carrie E. Schweitzer (2011). "A new Triassic decapod, Platykotta akaina, from the Arabian shelf of the northern United Arab Emirates: earliest occurrence of the Anomura". Paläontologische Zeitschrift 85 (1): 93–102. doi:10.1007/s12542-010-0080-y. Bibcode: 2011PalZ...85...93C. http://decapoda.nhm.org/pdfs/31744/31744.pdf. 
  43. ↑ Luque, J.; Feldmann, R. M.; Vernygora, O.; Schweitzer, C. E.; Cameron, C. B.; Kerr, K. A.; Vega, F. J.; Duque, A. et al. (24 April 2019). "Exceptional preservation of mid-Cretaceous marine arthropods and the evolution of novel forms via heterochrony". Science Advances 5 (4): eaav3875. doi:10.1126/sciadv.aav3875. PMID 31032408. Bibcode: 2019SciA....5.3875L. 
  44. ↑ 44.0 44.1 Jose C.E. Mendoza; Kin Onn Chan; Joelle C.Y. Lai; Brent P. Thoma; Paul F. Clark; Danièle Guinot; Darryl L. Felder; Peter K.L. Ng (2022). "A comprehensive molecular phylogeny of the brachyuran crab superfamily Xanthoidea provides novel insights into its systematics and evolutionary history". Molecular Phylogenetics and Evolution 177: 107627. doi:10.1016/j.ympev.2022.107627. PMID 36096461. 
  45. ↑ 45.0 45.1 Chandler T.T. Tsang; Christoph D. Schubart; Ka Hou Chu; Peter K.L. Ng; Ling Ming Tsang (2022). "Molecular phylogeny of Thoracotremata crabs (Decapoda, Brachyura): Toward adopting monophyletic superfamilies, invasion history into terrestrial habitats and multiple origins of symbiosis". Molecular Phylogenetics and Evolution 177: 107596. doi:10.1016/j.ympev.2022.107596. PMID 35914646. 
  46. ↑ B. B. Rossi (1969). The Crab Nebula: Ancient History and Recent Discoveries. Center for Space Research, Massachusetts Institute of Technology. CSR-P-69-27. https://ntrs.nasa.gov/search.jsp?R=19700008151. 
  47. ↑ Elizabeth Benson (1972). The Mochica: A Culture of Peru. New York, NY: Praeger Press. ISBN 978-0-500-72001-1. 
  48. ↑ Katherine Berrin; Larco Museum (1997). The Spirit of Ancient Peru:Treasures from the Museo Arqueológico Rafael Larco Herrera. New York: Thames and Hudson. pp. 216. ISBN 978-0-500-01802-6. 
  49. ↑ Kipling, Rudyard (1902). "The Crab that Played with the Sea". Just So Stories. Macmillan. http://etc.usf.edu/lit2go/79/just-so-stories/1297/the-crab-that-played-with-the-sea/. 
  50. ↑ Skeat, Walter William (1900). "Chapter 1: Nature". Malay Magic. London: Macmillan and Co., Limited. pp. 1–15. https://www.gutenberg.org/files/47873/47873-h/47873-h.htm#s1.2. 

External links

Wikidata ☰ Q40802 entry



Retrieved from "https://handwiki.org/wiki/index.php?title=Biology:Crab&oldid=3640788"