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70-514: Through folk etymology , the name also became associated with Latin grex (stem greg– ) meaning "flock" or "herd". This association with a shepherd who diligently guides his flock contributed to the name's popularity among monks and popes . Sixteen popes and two antipopes have used the name Gregorius, starting with Pope Gregory I (Gregory the Great). It is tied with Benedict as the second-most popular name for popes, after John . Although

140-475: A chestnut horse ' . This was an allusion to a fourteenth-century French morality poem, Roman de Fauvel , about a chestnut-coloured horse who corrupts men through duplicity. The phrase was reanalyzed in early Modern English by comparison to favour as early as 1510. Words need not completely disappear before their compounds are reanalyzed. The word shamefaced was originally shamefast . The original meaning of fast 'fixed in place' still exists, as in

210-480: A corn on the foot. The word comes from Old English ang- + nægel ' anguished nail, compressed spike ' , but the spelling and pronunciation were affected by folk etymology in the seventeenth century or earlier. Thereafter, the word came to be used for a tag of skin or torn cuticle near a fingernail or toenail. Several words in Medieval Latin were subject to folk etymology. For example,

280-573: A change in the form or meaning. To disambiguate the usage of the term "folk/popular etymology", Ghil'ad Zuckermann proposes a clear-cut distinction between the derivational-only popular etymology (DOPE) and the generative popular etymology (GPE): the DOPE refers to a popular false etymology involving no neologization , and the GPE refers to neologization generated by a popular false etymology. Examples of words created or changed through folk etymology include

350-462: A day-to-day basis, they consume what they can acquire in their immediate environment in limited space and time available - detritus . At a microbial level, the FPOM has a high surface area of organic particles and consists of a plethora of substrate and bacteria , fungi , micro-algae , meiofauna , partially decomposed organic material and mucus. This mucus or "slime" is a biofilm and can be felt on

420-499: A dozen genera . It is home to the world's three largest freshwater crayfish: Many of the better-known Australian crayfish are of the genus Cherax , and include the common yabby ( C. destructor ), western yabby ( C. preissii ), and red-claw crayfish ( C. quadricarinatus ). The marron species C. tenuimanus is critically endangered , while other large Australasian crayfish are threatened or endangered. In New Zealand , two species of Paranephrops are endemic, and are known by

490-510: A greater understanding of the creatures. The Protivin brewery in the Czech Republic uses crayfish outfitted with sensors to detect any changes in their bodies or pulse activity in order to monitor the purity of the water used in their product. The creatures are kept in a fish tank that is fed with the same local natural source water used in their brewing. If three or more of the crayfish have changes to their pulses, employees know there

560-480: A manner appropriate to that perceived origin. This popular etymologizing has had a powerful influence on the forms which words take. Examples in English include crayfish or crawfish , which are not historically related to fish but come from Middle English crevis , cognate with French écrevisse . Likewise chaise lounge , from the original French chaise longue ("long chair"), has come to be associated with

630-437: A similar manner include belfry (from berfrey ) by association with bell , female (from femelle ) by male , and penthouse (from apentis ) by house . The variant spelling of licorice as liquorice comes from the supposition that it has something to do with liquid. Anglo-Norman licoris (influenced by licor ' liquor ' ) and Late Latin liquirītia were respelled for similar reasons, though

700-452: A similar way to mammals. Then the stress hormone cortisol is released and this leads to the formation of lactic acid in the muscles, which makes the meat taste sour. Crayfish can be cooked more humanely by first freezing them unconscious for a few hours, then destroying the central nervous system along their abdomen by cutting the crayfish lengthwise with a long knife down the center of the crayfish before cooking it. Global crayfish production

770-425: A small portion of the diet by volume. They feed on submerged vegetable material at times, but their ability to catch large living animal material is restricted. They can feed on interstitial organisms if they can be grasped in the small feeding claws. They can be lured into traps with an array of baits from dog biscuits, fish heads, meat, etc., all of which reinforces the fact that they are generalist feeders. On

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840-462: A variety of ray-finned fishes , and are commonly used as bait , either live or with only the tail meat. They are a popular bait for catching catfish , largemouth bass , smallmouth bass , striped bass , perch , pike and muskie . When using live crayfish as bait, anglers prefer to hook them between the eyes, piercing through their hard, pointed beak which causes them no harm; therefore, they remain more active. When using crayfish as bait, it

910-475: A word or other form becomes obsolete, words or phrases containing the obsolete portion may be reanalyzed and changed. Some compound words from Old English were reanalyzed in Middle or Modern English when one of the constituent words fell out of use. Examples include bridegroom from Old English brydguma ' bride-man ' . The word gome ' man ' from Old English guma fell out of use during

980-496: Is hangmat . It was borrowed from Spanish hamaca (ultimately from Arawak amàca ) and altered by comparison with hangen and mat ' hanging mat ' . German Hängematte shares this folk etymology. Islambol , a folk etymology meaning 'Islam abounding', is one of the names of Istanbul used after the Ottoman conquest of 1453. An example from Persian is the word شطرنج shatranj 'chess', which

1050-426: Is a productive process in historical linguistics , language change , and social interaction . Reanalysis of a word's history or original form can affect its spelling, pronunciation, or meaning. This is frequently seen in relation to loanwords or words that have become archaic or obsolete. Folk/popular etymology may also refer to a popular false belief about the etymology of a word or phrase that does not lead to

1120-417: Is a change in a word or phrase resulting from the replacement of an unfamiliar form by a more familiar one through popular usage. The form or the meaning of an archaic, foreign, or otherwise unfamiliar word is reinterpreted as resembling more familiar words or morphemes . The term folk etymology is a loan translation from German Volksetymologie , coined by Ernst Förstemann in 1852. Folk etymology

1190-456: Is a portmanteau of wani ditata (dare to be controlled), also, wanita is taken from Sanskrit वनिता vanitā (someone desired by men). In Turkey, the political Democrat Party changed its logo in 2007 to a white horse in front of a red background because many voters folk-etymologized its Turkish name Demokrat as demir kırat ' iron white-horse ' . Crayfish Crayfish are freshwater crustaceans belonging to

1260-654: Is a potential for ecological damage when crayfish are introduced into non-native bodies of water: e.g., crayfish plague in Europe, or the introduction of the common yabby ( Cherax destructor ) into drainages east of the Great Dividing Range in Australia. Some public schools in the United States keep live crayfish in the classroom and have the students take care of them in order to give the students

1330-473: Is applied to saltwater species in some countries . The name "crayfish" comes from the Old French word escrevisse ( Modern French écrevisse ). The word has been modified to "crayfish" by association with "fish" ( folk etymology ). The largely American variant "crawfish" is similarly derived. Some kinds of crayfish are known locally as lobsters , crawdads, mudbugs, and yabbies . In

1400-471: Is caused by the North American water mold Aphanomyces astaci. This water mold was transmitted to Europe when North American species of crayfish were introduced. Species of the genus Astacus are particularly susceptible to infection, allowing the plague-coevolved signal crayfish (native to western North America) to invade parts of Europe . Acid rain can cause problems for crayfish across

1470-591: Is centered in Asia, primarily China. In 2018, Asian production accounted for 95% of the world's crawfish supply. Crayfish is part of Swedish cuisine and is usually eaten in August at special crayfish parties ( Swedish : Kräftskiva ). Documentation of the consumption of crayfish dates to at least the 16th century. On the Swedish west coast, Nephrops norvegicus ( Havskräfta , lit.   ' sea crayfish ' )

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1540-695: Is derived from the Sanskrit चतुरङ्ग chatur-anga ("four-army [game]"; 2nd century BCE), and after losing the u to syncope , became چترنگ chatrang in Middle Persian (6th century CE). Today it is sometimes factorized as sad ' hundred ' + ranj ' worry, mood ' , or ' a hundred worries ' . Some Indonesian feminists discourage usage of the term wanita ('woman') and replacing it with perempuan , since wanita itself has misogynistic roots. First, in Javanese , wanita

1610-751: Is found in the Pacific Northwest and the headwaters of some rivers east of the Continental Divide . Many crayfish are also found in lowland areas where the water is abundant in calcium , and oxygen rises from underground springs. Crayfish are also found in some non-coastal wetlands; eight species of crayfish live in Iowa , for example. In 1983, Louisiana designated the crayfish, or crawfish as they are commonly called, as its official state crustacean. Louisiana produces 100 million pounds (45 million kilograms) of crawfish per year with

1680-537: Is important to fish in the same environment where they were caught. An Illinois State University report that focused on studies conducted on the Fox River and Des Plaines River watershed stated that rusty crayfish , initially caught as bait in a different environment, were dumped into the water and "outcompeted the native clearwater crayfish". Other studies confirmed that transporting crayfish to different environments has led to various ecological problems, including

1750-467: Is in the end phase of decomposition and is recognised as black organic mud. The crayfish usually ingest the material in only a few minutes, as distinct from grazing for many hours. The material is mixed with digestive fluids and sorted by size. The finer particles follow a slower and more exacting route through to the hindgut , compared to the coarser material. The coarser material is eliminated first and often reappears in approximately 10 to 12 hours, whereas

1820-484: Is more commonly eaten while various freshwater crayfish are consumed in the rest of the country. Prior to the 1960s, crayfish was largely inaccessible to the urban population in Sweden and consumption was largely limited to the upper classes or farmers holding fishing rights in fresh water lakes. With the introduction of import of frozen crayfish the crayfish party is now widely practiced across all spheres in Sweden and among

1890-453: Is uncertain. By the late Middle Ages its meaning was extended to the holder of a university degree inferior to master or doctor. This was later re-spelled baccalaureus , probably reflecting a false derivation from bacca laurea ' laurel berry ' , alluding to the possible laurel crown of a poet or conqueror. In the fourteenth or fifteenth century, French scholars began to spell the verb savoir ' to know ' as sçavoir on

1960-462: Is unknown, but presumably humorous, since the dish contains no rabbit. In 1785 Francis Grose suggested in A Classical Dictionary of the Vulgar Tongue that the dish is "a Welch rare bit", though the word rarebit was not common prior to Grose's dictionary. Both versions of the name are in current use; individuals sometimes express strong opinions concerning which version is correct. When

2030-478: The Eastern United States , "crayfish" is more common in the north, while "crawdad" is heard more in central and southwestern regions, and "crawfish" farther south, although considerable overlaps exist. The study of crayfish is called astacology. The body of a decapod crustacean , such as a crab, lobster, or prawn (shrimp), is made up of twenty body segments grouped into two main body parts,

2100-622: The Italian agile frog and the painted frog in Malta . Crayfish are eaten worldwide. Like other edible crustaceans, only a small portion of the body of a crayfish is eaten. In most prepared dishes, such as soups, bisques and étouffées , only the tail portion is served. At crawfish boils or other meals where the entire body of the crayfish is presented, other portions, such as the claw meat, may be eaten. Research shows that crayfish do not die immediately when boiled alive, and respond to pain in

2170-646: The Late Triassic (~230-200 million years ago) Chinle Formation of North America, assigned to the species " Enoploclytia " porteri and Camborygma eumekenomos, which are not assigned to any modern families. An indeterminate member of the modern family Cambaridae is known from the Late Jurassic Morrison Formation of North America. The earliest records of other modern families date to the Early Cretaceous, including

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2240-531: The Māori name kōura . In Australia, New Zealand, and South Africa , the term "crayfish" or "cray" generally refers to a saltwater spiny lobster , of the genus Jasus that is indigenous to much of southern Oceania , while the freshwater species are usually called yabbies or kōura , from the indigenous Australian and Māori names for the animal, respectively, or by other names specific to each species. Exceptions include western rock lobster (of

2310-566: The National Park Service as well as video and anecdotal reports by aquarium owners indicate that crayfish will eat their moulted exoskeleton "to recover the calcium and phosphates contained in it." As omnivores, crayfish will eat almost anything; therefore, they may explore the edibility of aquarium plants in a fish tank. However, most species of dwarf crayfish, such as Cambarellus patzcuarensis , will not destructively dig or eat live aquarium plants. In some nations, such as

2380-609: The Northern Hemisphere and one in the Southern Hemisphere . The Southern Hemisphere ( Gondwana -distributed) family Parastacidae , with 14 extant genera and two extinct genera, live(d) in South America , Madagascar , and Australasia . They are distinguished by the absence of the first pair of pleopods . Of the other three Northern Hemisphere families (grouped in the superfamily Astacoidea ),

2450-692: The Palinuridae family) found on the west coast of Australia (it is a spiny lobster, but not of Jasus) ; the Tasmanian giant freshwater crayfish (from the Parastacidae family and therefore a true crayfish) found only in Tasmania; and the Murray crayfish found along Australia's Murray River . In Singapore , the term crayfish typically refers to Thenus orientalis , a seawater crustacean from

2520-679: The Swedish-speaking population of Finland . In the United States, crayfish production is strongly centered in Louisiana , with 93% of crayfish farms located in the state as of 2018. In 1987, Louisiana produced 90% of the crayfish harvested in the world, 70% of which were consumed locally. In 2007, the Louisiana crayfish harvest was about 54,800 tons, almost all of it from aquaculture . About 70–80% of crayfish produced in Louisiana are Procambarus clarkii (red swamp crawfish), with

2590-487: The United Kingdom , United States , Australia , and New Zealand , imported alien crayfish are a danger to local rivers. The three most widespread American species invasive in Europe are Faxonius limosus , Pacifastacus leniusculus and Procambarus clarkii . Crayfish may spread into different bodies of water because specimens captured for pets in one river are often released into a different catchment. There

2660-462: The cephalothorax and the abdomen . Each segment may possess one pair of appendages , although in various groups, these may be reduced or missing. On average, crayfish grow to 17.5 cm (6.9 in) in length. Walking legs have a small claw at the end. Crayfish are opportunistic omnivorous scavengers, with the ability to filter and process mud. In aquaculture ponds using isotope analysis they were shown to build body tissue selectively from

2730-702: The parastacid Palaeoechinastacus from Australia which is 115 million years old, the cambaroidid Palaeocambarus from the Yixian Formation of China which is likely around 120 million years old ( Barremian - Aptian ), and the astacid " Austropotamobius " llopisi from the Las Hoyas site in Spain (Barremian). Crayfish are susceptible to infections such as crayfish plague and to environmental stressors including acidification. In Europe, they are particularly threatened by crayfish plague, which

2800-447: The red swamp and white river crawfish being the main species harvested. Crawfish are a part of Cajun culture dating back hundreds of years. A variety of cottage industries have developed as a result of commercialized crawfish iconography. Their products include crawfish attached to wooden plaques, T-shirts with crawfish logos, and crawfish pendants, earrings, and necklaces made of gold or silver. Australia has over 100 species in

2870-524: The slipper lobster family. True crayfish are not native to Singapore, but are commonly found as pets, or as an invasive species ( Cherax quadricarinatus ) in the many water catchment areas, and are alternatively known as freshwater lobsters . In the United Kingdom and Ireland, the terms crayfish or crawfish commonly refer to the European spiny lobster , a saltwater species found in much of

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2940-669: The East Atlantic and Mediterranean. The only true crayfish species native to the British Isles is the endangered white clawed crayfish . Fossil burrows very similar in construction to those of modern crayfish and likely produced by early crayfish are known from the Early Permian (~300-270 million years ago) of equatorial Pangea , in what is now North America ( Washington Formation ), and Europe ( Sardinia ). The oldest body fossils assigned to crayfish are known from

3010-415: The English dialectal form sparrowgrass , originally from Greek ἀσπάραγος (" asparagus ") remade by analogy to the more familiar words sparrow and grass . When the alteration of an unfamiliar word is limited to a single person, it is known as an eggcorn . The technical term "folk etymology" refers to a change in the form of a word caused by erroneous popular suppositions about its etymology . Until

3080-789: The Theologian (also known as Gregory of Nazianzus ) is one of the Three Hierarchs (Ancient Greek: Οἱ Τρεῖς Ἱεράρχαι; Greek: Οι Τρεις Ιεράρχες). The other two are Basil the Great, also known as Basil of Caesarea and John Chrysostom . All three have separate feast days in January: Basil on January 1, Gregory on January 25, and Chrysostom on January 27. Folk etymology Folk etymology – also known as (generative) popular etymology , analogical reformation , (morphological) reanalysis and etymological reinterpretation –

3150-403: The academic development of comparative linguistics and description of laws underlying sound changes , the derivation of a word was mostly guess-work. Speculation about the original form of words in turn feeds back into the development of the word and thus becomes a part of a new etymology. Believing a word to have a certain origin, people begin to pronounce, spell, or otherwise use the word in

3220-399: The animal protein portion of pelleted food and not the other components of the pellet. They have the potential to eat most foods, even nutrient poor material such as grass, leaves, and paper, but can be highly selective and need variety to balance their diet. The personalities of the individual crayfish can be a key determinant in the food preference behaviour in aquaria. Crayfish all over

3290-469: The compound becomes obsolete. There are many examples of words borrowed from foreign languages, and subsequently changed by folk etymology. The spelling of many borrowed words reflects folk etymology. For example, andiron borrowed from Old French was variously spelled aundyre or aundiren in Middle English, but was altered by association with iron . Other Old French loans altered in

3360-632: The compounded words steadfast and colorfast , but by itself mainly in frozen expressions such as stuck fast , hold fast , and play fast and loose . The songbird wheatear or white-ear is a back-formation from Middle English whit-ers ' white arse ' , referring to the prominent white rump found in most species. Although both white and arse are common in Modern English, the folk etymology may be euphemism . Reanalysis of archaic or obsolete forms can lead to changes in meaning as well. The original meaning of hangnail referred to

3430-411: The diet of these creatures was considered too complex since the first book ever written in the field of zoology, The Crayfish by T.H. Huxley (1879), where they were described as " detritivores ". This is why most researchers have not attempted to understand the diet of freshwater crayfish. The most complex study which matched the structure and function of the whole digestive track with ingested material

3500-505: The elimination of native species. Transporting crayfish as live bait has also contributed to the spread of zebra mussels in various waterways throughout Europe and North America, as they are known to attach themselves to exoskeleton of crayfishes. Crayfish are kept as pets in freshwater aquariums. They prefer foods like shrimp pellets or various vegetables, but will also eat tropical fish food, regular fish food, algae wafers, and small fish that can be captured with their claws. A report by

3570-467: The false belief it was derived from Latin scire ' to know ' . In fact it comes from sapere ' to be wise ' . The Italian word liocorno , meaning 'unicorn' derives from 13th-century lunicorno ( lo 'the' + unicorno 'unicorn'). Folk etymology based on lione 'lion' altered the spelling and pronunciation. Dialectal liofante 'elephant' was likewise altered from elefante by association with lione . The Dutch word for ' hammock '

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3640-542: The finer material is usually eliminated from 16 to 26 hours after ingestion. All waste products coming out through the hindgut are wrapped in a peritrophic membrane , so they look like a tube. Such an investment in the wrapping of the microbial free faeces in a protein rich membrane is most likely the reason they are coprophagic. Such feeding behaviour based on selection, ingestion, and extreme processing ensures periodic feeding, as distinct from continuous grazing. They tend to eat to satiation and then take many hours to process

3710-422: The four genera of the family Astacidae live in western Eurasia and western North America , the 15 genera of the family Cambaridae live in eastern North America , and the single genus of Cambaroididae live in eastern Asia . The greatest diversity of crayfish species is found in southeastern North America, with over 330 species in 15 genera, all in the family Cambaridae. A further genus of astacid crayfish

3780-557: The infraorder Astacidea , which also contains lobsters . Taxonomically, they are members of the superfamilies Astacoidea and Parastacoidea . They breathe through feather-like gills . Some species are found in brooks and streams, where fresh water is running, while others thrive in swamps , ditches, and paddy fields . Most crayfish cannot tolerate polluted water , although some species, such as Procambarus clarkii , are hardier. Crayfish feed on animals and plants, either living or decomposing , and detritus . The term "crayfish"

3850-477: The letter s is the result of comparison with the synonym isle from Old French and ultimately as a Latinist borrowing of insula , though the Old French and Old English words are not historically related. In a similar way, the spelling of wormwood was likely affected by comparison with wood . The phrase curry favour , meaning to flatter, comes from Middle English curry favel ' groom

3920-425: The material, leaving minimal chance of having more room to ingest other items. Crayfish usually have limited home range and so they rest, digest, and eliminate their waste, most commonly in the same location each day. Feeding exposes the crayfish to risk of predation, and so feeding behaviour is often rapid and synchronised with feeding processes that reduce such risks — eat, hide, process and eliminate. Knowledge of

3990-444: The name comes from the fact that the trees bloom in spring, a time when circuit-riding preachers resume church services or when funeral services are carried out for people who died during the winter. A seemingly plausible but no less speculative etymology accounts for the form of Welsh rarebit , a dish made of cheese and toasted bread. The earliest known reference to the dish in 1725 called it Welsh rabbit . The origin of that name

4060-424: The name was uncommon in the early 20th century, after the popularity of the actor Gregory Peck it became one of the ten most common male names in the United States in the 1950s and has remained popular since. The Roman Catholic Church traditionally held the feast of Saint Gregory (the Great) on March 12, but changed it to September 3 in 1969. March 12 remains the name day for Gregory in most countries. Gregory

4130-411: The orange tree ' , with the initial ⟨n⟩ of naranj understood as part of the article . Rebracketing in the opposite direction saw the Middle English a napron become an apron . In back-formation, a new word is created by removing elements from an existing word that are interpreted as affixes . For example, Italian pronuncia ' pronunciation, accent ' is derived from

4200-437: The remaining 20–30% being Procambarus zonangulus (white river crawfish). Optimum dietary nutritional requirement of freshwater crayfish, or crayfish nutrient specifications are now available for aquaculture feed producers Like all crustaceans, crayfish are not kosher because they are aquatic animals that do not have both fins and scales . They are therefore not eaten by observant Jews . Crayfish are preyed upon by

4270-402: The sixteenth century and the compound was eventually reanalyzed with the Modern English word groom ' male servant ' . A similar reanalysis caused sandblind , from Old English sāmblind ' half-blind ' with a once-common prefix sām- ' semi- ' , to be respelled as though it is related to sand . The word island derives from Old English igland . The modern spelling with

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4340-434: The surface of leaves and sticks. Also crayfish have been shown to be coprophagic - eating their own faeces, they also eat their own exuviae ( moulted carapace ) and each other. They have even been observed leaving the water to graze. Detritus or mud is a mixture of dead plankton (plant and animal), organic wastes from the water column , and debris derived from the aquatic and terrestrial environments. Mostly detritus

4410-534: The term an additional meaning of "hopeless venture". Sometimes imaginative stories are created to account for the link between a borrowed word and its popularly assumed sources. The names of the serviceberry , service tree , and related plants, for instance, come from the Latin name sorbus . The plants were called syrfe in Old English, which eventually became service . Fanciful stories suggest that

4480-503: The ultimate origin of all three is Ancient Greek γλυκύρριζα glucúrrhiza ' sweet root ' . Reanalysis of loan words can affect their spelling, pronunciation, or meaning. The word cockroach , for example, was borrowed from Spanish cucaracha but was assimilated to the existing English words cock and roach . The phrase forlorn hope originally meant "storming party, body of skirmishers" from Dutch verloren hoop "lost troop". But confusion with English hope has given

4550-403: The verb pronunciare ' to pronounce, to utter ' and English edit derives from editor . Some cases of back-formation are based on folk etymology. In linguistic change caused by folk etymology, the form of a word changes so that it better matches its popular rationalisation. Typically this happens either to unanalysable foreign words or to compounds where the word underlying one part of

4620-405: The word widerdonum meaning 'reward' was borrowed from Old High German widarlōn ' repayment of a loan ' . The l   →   d alteration is due to confusion with Latin donum ' gift ' . Similarly, the word baceler or bacheler (related to modern English bachelor ) referred to a junior knight. It is attested from the eleventh century, though its ultimate origin

4690-399: The word lounge . Other types of language change caused by reanalysis of the structure of a word include rebracketing and back-formation . In rebracketing, users of the language change, misinterpret, or reinterpret the location of a boundary between words or morphemes . For example, the Old French word orenge ' orange tree ' comes from Arabic النَّرَنْج an-naranj '

4760-436: The world can be seen in an ecological role of benthic dwellers, so this is where most of their food is obtained - at the sediment/water interface in ponds, lakes, swamps, or burrows. When the gut contents are analysed, most of the contents is mud: fine particulate organic matter (FPOM) and mixed particles of lignin and cellulose (roots, leaves, bark, wood). Some animal material can also be identified, but this only contributes

4830-641: The world. In whole-ecosystem experiments simulating acid rain at the Experimental Lakes Area in Ontario, Canada , crayfish populations crashed – probably because their exoskeletons are weaker in acidified environments. In several countries, particularly in Europe, native species of crayfish are under threat by imported species, particularly the signal crayfish ( Pacifastacus leniusculus ). Crayfish are also considered an invasive predatory species, endangering native European species such as

4900-519: Was performed in the 1990s by Brett O'Brien on marron , the least aggressive of the larger freshwater crayfish with aquaculture potential, similar to redclaw and yabbies. Crayfish are closely related to lobsters , and together they belong to the infraorder Astacidea . Their phylogeny can be shown in the simplified cladogram below: Enoplometopidae Nephropidae Parastacidae Cambaroididae Astacidae Cambaridae Four extant (living) families of crayfish are described, three in

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