In biology , a common name of a taxon or organism (also known as a vernacular name , English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrasted with the scientific name for the same organism, which is often based in Latin . A common name is sometimes frequently used, but that is not always the case.
75-430: See text Pectenidae Scallop ( / ˈ s k ɒ l ə p , ˈ s k æ l ə p / ) is a common name that encompasses various species of marine bivalve mollusks in the taxonomic family Pectinidae , the scallops. However, the common name "scallop" is also sometimes applied to species in other closely related families within the superfamily Pectinoidea , which also includes the thorny oysters . Scallops are
150-504: A cosmopolitan family of bivalves found in all of the world's oceans, although never in fresh water. They are one of the very few groups of bivalves to be primarily "free-living", with many species capable of rapidly swimming short distances and even migrating some distance across the ocean floor. A small minority of scallop species live cemented to rocky substrates as adults, while others attach themselves to stationary or rooted objects such as seagrass at some point in their lives by means of
225-774: A flora of his homeland Sweden, Flora Svecica (1745), and in this, he recorded the Swedish common names, region by region, as well as the scientific names. The Swedish common names were all binomials (e.g. plant no. 84 Råg-losta and plant no. 85 Ren-losta); the vernacular binomial system thus preceded his scientific binomial system. Linnaean authority William T. Stearn said: By the introduction of his binomial system of nomenclature, Linnaeus gave plants and animals an essentially Latin nomenclature like vernacular nomenclature in style but linked to published, and hence relatively stable and verifiable, scientific concepts and thus suitable for international use. The geographic range over which
300-599: A common sight on beaches and are often brightly coloured, making them a popular object to collect among beachcombers and vacationers. The shells also have a significant place in popular culture. Scallops inhabit all the oceans of the world, with the largest number of species living in the Indo-Pacific region. Most species live in relatively shallow waters from the low tide line to 100 m, while others prefer much deeper water. Although some species only live in very narrow environments, most are opportunistic and can live under
375-452: A detectable difference in anaerobic energy expenditure than those without encrustation. In the absence of barnacle encrustation, individual scallops swim significantly longer, travel further, and attain greater elevation. The family name Pectinidae, which is based on the name of the type genus, Pecten , comes from the Latin pecten meaning comb , in reference to a comb-like structure of
450-440: A filament they secrete called a byssal thread . The majority of species, however, live recumbent on sandy substrates, and when they sense the presence of a predator such as a starfish , they may attempt to escape by swimming swiftly but erratically through the water using jet propulsion created by repeatedly clapping their shells together. Scallops have a well-developed nervous system, and unlike most other bivalves all scallops have
525-479: A given animal is "facing" requires detailed information about its valves. The model scallop shell consists of two similarly shaped valves with a straight hinge line along the top, devoid of teeth, and producing a pair of flat wings or "ears" (sometimes called "auricles", though this is also the term for two chambers in its heart) on either side of its midpoint, a feature which is unique to and apparent in all adult scallops. These ears may be of similar size and shape, or
600-551: A hard substrate (e.g. Chlamys distorta and Hinnites multirigosus ). However, the majority of scallops are free-living and can swim with brief bursts of speed to escape predators (mostly starfish ) by rapidly opening and closing their valves. Indeed, everything about their characteristic shell shape – its symmetry, narrowness, smooth and/ or grooved surface, small flexible hinge, powerful adductor muscle, and continuous and uniformly curved edge – facilitates such activity. They often do this in spurts of several seconds before closing
675-485: A particularly common name is used varies; some common names have a very local application, while others are virtually universal within a particular language. Some such names even apply across ranges of languages; the word for cat , for instance, is easily recognizable in most Germanic and many Romance languages . Many vernacular names, however, are restricted to a single country and colloquial names to local districts. Some languages also have more than one common name for
750-524: A physical barrier around byssal openings to prevent sea stars from inserting their digestive membranes. Sponge encrustation protects C. hastata from barnacle larvae settlement, serving as a protection from epibionts that increase susceptibility to predators. Thus, barnacle larvae settlement occurs more frequently on sponge-free shells than on sponge-encrusted shells. In fact, barnacle encrustation negatively influences swimming in C. hastata . Those swimming with barnacle encrustation require more energy and show
825-588: A ring of numerous simple eyes situated around the edge of their mantles . Many species of scallops are highly prized as a food source, and some are farmed as aquaculture . The word "scallop" is also applied to the meat of these bivalves, the adductor muscle , that is sold as seafood . The brightly coloured, symmetric, fan-shaped shells of scallops with their radiating and often fluted ornamentation are valued by shell collectors, and have been used since ancient times as motifs in art, architecture, and design. Owing to their widespread distribution, scallop shells are
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#1732773053558900-401: A row before becoming completely exhausted and requiring several hours of rest. Should a swimming scallop land on its left side, it is capable of flipping itself over to its right side via a similar shell-clapping movement called the righting reflex. So-called singing scallops are rumored to make an audible, soft popping sound as they flap their shells underwater (though whether or not this happens
975-555: A vital defense mechanism for avoiding predators. Though rather weak, their series of eyes can detect surrounding movement and alert precaution in the presence of predators, most commonly sea stars, crabs, and snails. Physiological fitness and exercise of scallops decrease with age due to the decline of cellular and especially mitochondrial function, thus increasing the risk of capture and lowering rates of survival. Older individuals show lower mitochondrial volume density and aerobic capacity, as well as decreased anaerobic capacity construed from
1050-455: A wide variety of conditions. Scallops can be found living within, upon, or under either rocks, coral, rubble, sea grass , kelp , sand, or mud. Most scallops begin their lives as byssally attached juveniles, an ability that some retain throughout their lives while others grow into free-living adults. Very little variation occurs in the internal arrangement of organs and systems within the scallop family, and what follows can be taken to apply to
1125-508: Is a characteristic that has evolved within the lineage. In a 2008 paper, Puslednik et al. identified considerable convergence of shell morphology in a subset species of gliding Pectinidae, which suggests iterative morphological evolution may be more prevalent in the family than previously believed. There have been a number of efforts to address phylogenetic studies. Only three have assessed more than ten species and only one has included multiple outgroups. Nearly all previous molecular analyses of
1200-525: Is based on molecular phylogeny using mitochondrial (12S, 16S) and nuclear (18S, 28S, and H3) gene markers by Yaron Malkowsky and Annette Klussmann-Kolb in 2012. Palliolinae (in part) [REDACTED] Palliolinae (in part) and Camptonectinae Chlamydinae [REDACTED] (70 mya) Pecten [REDACTED] Flexopecten [REDACTED] (247 mya) Aequipecten [REDACTED] Limidae (file shells) [REDACTED] other Pteriomorphia ( oysters , mussels ) [REDACTED] Scallops are
1275-479: Is controlled by three paired ganglia located at various points throughout their anatomy, the cerebral or cerebropleural ganglia, the pedal ganglia, and the visceral or parietovisceral ganglia. All are yellowish. The visceral ganglia are by far the largest and most extensive of the three, and occur as an almost-fused mass near the center of the animal – proportionally, these are the largest and most intricate sets of ganglia of any modern bivalve. From this, radiate all of
1350-638: Is found in modern scallops only; both putative ancestors of modern scallops, the entoliids and the Aviculopectinidae, did not possess it. Like the true oysters (family Ostreidae ), scallops have a single central adductor muscle, thus, the inside of their shells has a characteristic central scar, marking the point of attachment for this muscle. The adductor muscle of scallops is larger and more developed than those of oysters , because scallops are active swimmers; some species of scallops are known to move en masse from one area to another. In scallops,
1425-461: Is in these remarks from a book on marine fish: In scientific binomial nomenclature, names commonly are derived from classical or modern Latin or Greek or Latinised forms of vernacular words or coinages; such names generally are difficult for laymen to learn, remember, and pronounce and so, in such books as field guides, biologists commonly publish lists of coined common names. Many examples of such common names simply are attempts to translate
1500-493: Is one of the largest marine bivalve families and contains over 300 extant species in 60 genera. Its origin dates back to the Middle Triassic Period, approximately 240 million years ago; in terms of diversity, it has been a thriving family to the present day. Evolution from its origin has resulted in a successful and diverse group: pectinids are present in the world's seas, found in environments ranging from
1575-406: Is open to some debate). Other scallops can extend their foot from between their valves, and by contracting the muscles in their foot, they can burrow into sand. Most species of the scallop family are free-living, active swimmers, propelling themselves through the water through the adductor muscles to open and close their shells. Swimming occurs through the clapping of valves for water intake. Closing
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#17327730535581650-408: Is sometimes equivocal, and information about phylogeny and relationships of the species are minimal, not the least because most work has been based only on adult morphology . This family's earliest and most comprehensive taxonomic treatments were based on macroscopic morphological characters of the adult shells and represent broadly divergent classification schemes. Some level of taxonomic stability
1725-659: Is the Cape dikkop (or "gewone dikkop", not to mention the presumably much older Zulu name "umBangaqhwa"); Burhinus vermiculatus is the "water dikkop". The thick joints in question are not even, in fact, the birds' knees, but the intertarsal joints —in lay terms the ankles. Furthermore, not all species in the genus have "thick knees", so the thickness of the "knees" of some species is not of clearly descriptive significance. The family Burhinidae has members that have various common names even in English, including " stone curlews ", so
1800-414: The D'Entrecasteaux Channel in the south of Tasmania dredging was banned in 1969, and since then divers have caught them in this area. Attempts to use lighted pots to attract lobster and crab led to the discovery that they were effective in attracting scallops. Common name In chemistry , IUPAC defines a common name as one that, although it unambiguously defines a chemical, does not follow
1875-519: The ICZN has formal rules for biological nomenclature and convenes periodic international meetings to further that purpose. The form of scientific names for organisms, called binomial nomenclature , is superficially similar to the noun-adjective form of vernacular names or common names which were used by non-modern cultures. A collective name such as owl was made more precise by the addition of an adjective such as screech . Linnaeus himself published
1950-406: The heterokonts and dinoflagellates . Some scallops, including Chlamys hastata , frequently carry epibionts such as sponges and barnacles on their shells. The relationship of the sponge to the scallop is characterized as a form of mutualism, because the sponge provides protection by interfering with adhesion of predatory sea-star tube feet, camouflages Chlamys hastata from predators, or forms
2025-576: The Hebrew Language publish from time to time short dictionaries of common name in Hebrew for species that occur in Israel or surrounding countries e.g. for Reptilia in 1938, Osteichthyes in 2012, and Odonata in 2015. Beak (bivalve) The beak is part of the shell of a bivalve mollusk , i.e. part of the shell of a saltwater or freshwater clam. The beak is the basal projection of
2100-661: The Pectinidae have only utilized mitochondrial data. Phylogenies based only on mitochondrial sequence data do not always provide an accurate estimation on the species tree. Complicated factors can arise due to the presence of genetic polymorphisms in ancestral species and resultant lineage sorting. In molecular phylogenies of the Bivalvia, both the Spondylidae and the Propeamussiidae have been resolved as sister to
2175-511: The Pectinidae. The following are recognised in the family Pectinidae: The largest wild scallop fishery is for the Atlantic sea scallop ( Placopecten magellanicus ) found off the northeastern United States and eastern Canada. Scallops are harvested using scallop dredges or bottom trawls. Most of the rest of the world's production of scallops is from Japan (wild, enhanced, and aquaculture) and China (mostly cultured Atlantic bay scallops). In
2250-710: The SSAR switched to an online version with a searchable database. Standardized names for the amphibians and reptiles of Mexico in Spanish and English were first published in 1994, with a revised and updated list published in 2008. A set of guidelines for the creation of English names for birds was published in The Auk in 1978. It gave rise to Birds of the World: Recommended English Names and its Spanish and French companions. The Academy of
2325-534: The Secretariat for the AFNC. SSA is an accredited Standards Australia (Australia's peak non-government standards development organisation) Standards Development The Entomological Society of America maintains a database of official common names of insects, and proposals for new entries must be submitted and reviewed by a formal committee before being added to the listing. Efforts to standardize English names for
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2400-580: The abundance of species within the Pectinidae has varied greatly over time; Pectinidae was the most diverse bivalve family in the Mesozoic era , but the group almost disappeared completely by the end of the Cretaceous period . The survivors speciated rapidly during the Tertiary period . Nearly 7,000 species and subspecies names have been introduced for both fossil and recent Pectinidae. The cladogram
2475-585: The amount of glycogen stored in muscle tissue. Environmental factors, such as changes in oxidative stress parameters, can inhibit the growth and development of scallops. Seasonal changes in temperature and food availability have been shown to affect muscle metabolic capabilities. The properties of mitochondria from the phasic adductor muscle of Euvola ziczac varied significantly during their annual reproductive cycle. Summer scallops in May have lower maximal oxidative capacities and substrate oxidation than any other time in
2550-505: The amphibians and reptiles of North America (north of Mexico) began in the mid-1950s. The dynamic nature of taxonomy necessitates periodical updates and changes in the nomenclature of both scientific and common names. The Society for the Study of Amphibians and Reptiles (SSAR) published an updated list in 1978, largely following the previous established examples, and subsequently published eight revised editions ending in 2017. More recently
2625-407: The anatomy of any given scallop species. The shell of a scallop consists of two sides or valves , a left valve and a right one, divided by a plane of symmetry . Most species of scallops rest on their right valve, and consequently, this valve is often deeper and more rounded than the left (i.e., upper) valve, which in many species is actually concave. With the hinge of the two valves oriented towards
2700-453: The animal sense its position in the surrounding environment. They are connected to the pedal ganglia by short cerebral-pedal connectives. The pedal ganglia, though not fused, are situated very close to each other near the midline. From the pedal ganglia, the scallop puts out pedal nerves which control the movement of, and sensation in, its small muscular foot. Scallops have a large number (up to 200) of small (about 1 mm) eyes arranged along
2775-428: The anterior ear may be somewhat larger (the posterior ear is never larger than the anterior one, an important feature for distinguishing which valve is which). As is the case in almost all bivalves, a series of lines and/or growth rings originates at the center of the hinge, at a spot called the " beak " surrounded by a generally raised area called the " umbo ". These growth rings increase in size downwards until they reach
2850-515: The author introduced into it so many new English names, that are to be found in no dictionary, and that do not preclude the necessity of learning with what Latin names they are synonymous. A tolerable idea may be given of the danger of too great a multiplicity of vulgar names, by imagining what geography would be, or, for instance, the Post-office administration, supposing every town had a totally different name in every language. Various bodies and
2925-493: The authors of many technical and semi-technical books do not simply adapt existing common names for various organisms; they try to coin (and put into common use) comprehensive, useful, authoritative, and standardised lists of new names. The purpose typically is: Other attempts to reconcile differences between widely separated regions, traditions, and languages, by arbitrarily imposing nomenclature, often reflect narrow perspectives and have unfortunate outcomes. For example, members of
3000-408: The choice of the name "thick-knees" is not easy to defend but is a clear illustration of the hazards of the facile coinage of terminology. For collective nouns for various subjects, see a list of collective nouns (e.g. a flock of sheep, pack of wolves). Some organizations have created official lists of common names, or guidelines for creating common names, hoping to standardize
3075-483: The combined sensitivity of both retinas to light entering the eye and light retro-reflected from the mirror grants scallops exceptional contrast definition, as well as the ability to detect changing patterns of light and motion. Scallops primarily rely on their eyes as an 'early-warning' threat detection system, scanning around them for movement and shadows which could potentially indicate predators. Additionally, some scallops alter their swimming or feeding behaviour based on
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3150-569: The concentric rings of their shells. Many scallops are hermaphrodites (having female and male organs simultaneously), altering their sex throughout their lives, while others exist as dioecious species, having a definite sex. In this case, males are distinguished by roe-containing white testes and females with roe-containing orange ovaries. At the age of two, they usually become sexually active, but do not contribute significantly to egg production until four. The reproduction process occurs externally through spawning, in which eggs and sperm are released into
3225-441: The current systematic naming convention, such as acetone , systematically 2-propanone , while a vernacular name describes one used in a lab, trade or industry that does not unambiguously describe a single chemical, such as copper sulfate , which may refer to either copper(I) sulfate or copper(II) sulfate. Sometimes common names are created by authorities on one particular subject, in an attempt to make it possible for members of
3300-406: The curved ventral edge of the shell. The shells of most scallops are streamlined to facilitate ease of movement during swimming at some point in their lifecycles, while also providing protection from predators. Scallops with ridged valves have the advantage of the architectural strength provided by these ridges called "ribs", although the ribs are somewhat costly in weight and mass. A unique feature of
3375-442: The edge of their mantles. These eyes represent a particular innovation among molluscs, relying on a concave, parabolic mirror of guanine crystals to focus and retro-reflect light instead of a lens as found in many other eye types. Additionally, their eyes possess a double-layered retina, the outer retina responding most strongly to light and the inner to abrupt darkness. While these eyes are unable to resolve shapes with high fidelity,
3450-411: The family Pectinidae is monophyletic, developing from a single common ancestor. The direct ancestors of Pectinidae were scallop-like bivalves of the family Entoliidae. Entoliids had auricles and a byssal notch only at youth, but they did not have a ctenolium, a comb-like arrangement along the margins of the byssal notch in Pectinidae. The ctenolium is the defining feature of the modern family Pectinidae and
3525-420: The family Pectinidae, marine bivalve molluscs within the superfamily Pectinoidea . Other families within this same superfamily share a somewhat similar overall shell shape, and some species within some of the related families are also commonly referred to as "scallops" (for example, Propeamussiidae , the glass scallops). The family Pectinidae is the most diversified of the pectinoideans in present-day oceans. It
3600-410: The food is digested in the digestive gland, an organ sometimes misleadingly referred to as the "liver, " which envelops part of the oesophagus, intestine, and entire stomach. Waste is passed on through the intestine (the terminus of which, like that of many mollusks, enters and leaves the animal's heart) and exits via the anus. Like all bivalves, scallops lack actual brains. Instead, their nervous system
3675-464: The general public (including such interested parties as fishermen, farmers, etc.) to be able to refer to one particular species of organism without needing to be able to memorise or pronounce the scientific name. Creating an "official" list of common names can also be an attempt to standardize the use of common names, which can sometimes vary a great deal between one part of a country and another, as well as between one country and another country, even where
3750-522: The genus Burhinus occur in Australia, Southern Africa, Eurasia, and South America. A recent trend in field manuals and bird lists is to use the name " thick-knee " for members of the genus. This, in spite of the fact that the majority of the species occur in non-English-speaking regions and have various common names, not always English. For example, "Dikkop" is the centuries-old South African vernacular name for their two local species: Burhinus capensis
3825-498: The intertidal zone to the hadal depths. The Pectinidae play an extremely important role in many benthic communities and exhibit a wide range of shell shapes, sizes, sculptures, and cultures. Raines and Poppe listed nearly 900 species names of scallops, but most of these are considered either questionable or invalid. Raines and Poppe mentioned over 50 genera, around 250 species, and subspecies . Although species are generally well-circumscribed, their attribution to subfamilies and genera
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#17327730535583900-711: The modern (now binding) International Code of Nomenclature for algae, fungi, and plants contains the following: Art. 68. Every friend of science ought to be opposed to the introduction into a modern language of names of plants that are not already there unless they are derived from a Latin botanical name that has undergone but a slight alteration. ... ought the fabrication of names termed vulgar names, totally different from Latin ones, to be proscribed. The public to whom they are addressed derives no advantage from them because they are novelties. Lindley's work, The Vegetable Kingdom, would have been better relished in England had not
3975-500: The muscular foot, used to attach to a firm support, such as a rock. Some can also be found on the ocean floor, moving with an extendable foot between their valves or burrowing themselves in the sand by extending and retracting their feet. Scallops are highly sensitive to shadows, vibrations, water movement, and chemical stimuli. All possess a series of 100 blue eyes, embedded on the edge of the mantle of their upper and lower valves that can distinguish between light and darkness. They serve as
4050-407: The nerves which connect the visceral ganglia to the circumpallial nerve ring which loops around the mantle and connects to all of the scallop's tentacles and eyes. This nerve ring is so well developed that, in some species, it may be legitimately considered an additional ganglion. The visceral ganglia are also the origin of the branchial nerves which control the scallop's gills. The cerebral ganglia are
4125-407: The next-largest set of ganglia and lie distinct from each other a significant distance dorsal to the visceral ganglia. They are attached to the visceral ganglia by long cerebral-visceral connectives, and to each other via a cerebral commissure that extends in an arch dorsally around the esophagus. The cerebral ganglia control the scallop's mouth via the palp nerves and connect to statocysts which help
4200-531: The ocean floor, where they attach themselves to objects through byssus threads. Byssus is eventually lost with adulthood, transitioning almost all scallop species into free swimmers. Rapid growth occurs within the first several years, with an increase of 50–80 % in shell height and quadrupled size in meat weight, and reaches a commercial size at about four to five years of age. The lifespans of some scallops have been known to extend over 20 years. Scallops are known to be infected by viruses , bacteria , microalgae of
4275-468: The oldest part of the valve of the adult animal. The beak usually, but not always, coincides with the umbo , the highest and most prominent point on the valve. Because by definition, all bivalves have two valves, the shell of a bivalve has two umbones, and two beaks. In many species of bivalves the beaks point towards one another. However, in some species of bivalves the beaks point posteriorly, in which case they are referred to as opisthogyrate; in others
4350-488: The same animal. For example, in Irish, there are many terms that are considered outdated but still well-known for their somewhat humorous and poetic descriptions of animals. w/ literal translations of the poetic terms Common names are used in the writings of both professionals and laymen . Lay people sometimes object to the use of scientific names over common names, but the use of scientific names can be defended, as it
4425-576: The same language is spoken in both places. A common name intrinsically plays a part in a classification of objects, typically an incomplete and informal classification, in which some names are degenerate examples in that they are unique and lack reference to any other name, as is the case with say, ginkgo , okapi , and ratel . Folk taxonomy , which is a classification of objects using common names, has no formal rules and need not be consistent or logical in its assignment of names, so that say, not all flies are called flies (for example Braulidae ,
4500-474: The scallop family is the presence, at some point during the animal's lifecycle, of a distinctive and taxonomically important shell feature, a comb-like structure called a ctenolium located on the anterior edge of the right valve next to the valve's byssal notch. Though many scallops lose this feature as they become free-swimming adults, all scallops have a ctenolium at some point during their lives, and no other bivalve has an analogous shell feature. The ctenolium
4575-402: The scientific name into English or some other vernacular. Such translation may be confusing in itself, or confusingly inaccurate, for example, gratiosus does not mean "gracile" and gracilis does not mean "graceful". The practice of coining common names has long been discouraged; de Candolle's Laws of Botanical Nomenclature , 1868, the non-binding recommendations that form the basis of
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#17327730535584650-408: The sea floor between each contraction of its valves, whereas a swimming scallop stays in the water column for most or all of its contractions and travels a much greater distance (though seldom at a height of more than 1 m off the sea bed and seldom for a distance of greater than 5 m). Both jumping and swimming movements are very energy-intensive, and most scallops cannot perform more than four or five in
4725-474: The shell entirely and sinking back to the bottom of their environment. Scallops are able to move through the water column either forward/ventrally (termed swimming) by sucking water in through the space between their valves, an area called the gape, and ejecting it through small holes near the hinge line called exhalant apertures, or backward/dorsally (termed jumping) by ejecting the water out the same way it came in (i.e. ventrally). A jumping scallop usually lands on
4800-411: The shell shape tends to be highly regular, and is commonly used as an archetypal form of a seashell . Scallops possess fast ( striated ) and slow ( smooth ) adductor muscles , which have different structures and contractile properties. These muscles lie closely apposed to one another but are divided by a connective tissue sheet. The striated adductor muscle contracts very quickly for swimming, whereas
4875-562: The shell which is situated next to the byssal notch. The fossil history of scallops is rich in species and specimens. The earliest known records of true scallops (those with a ctenolium) can be found from the Triassic period , over 200 million years ago. The earliest species were divided into two groups, one with a nearly smooth exterior: Pleuronectis von Schlotheim, 1820, while the other had radial ribs or riblets and auricles: Praechlamys Allasinaz, 1972. Fossil records also indicate that
4950-400: The smooth catch adductor muscle lacks striations, and contracts for long periods, keeping shells closed with little expenditure of energy. Scallops are filter feeders , and eat plankton . Unlike many other bivalves, they lack siphons . Water moves over a filtering structure, where food particles become trapped in mucus. Next, the cilia on the structure move the food toward the mouth. Then,
5025-407: The so-called "bee lice") and not every animal called a fly is indeed a fly (such as dragonflies and mayflies ). In contrast, scientific or biological nomenclature is a global system that attempts to denote particular organisms or taxa uniquely and definitively , on the assumption that such organisms or taxa are well-defined and generally also have well-defined interrelationships; accordingly
5100-403: The top, one side corresponds to the animal's morphological anterior or front, the other is the posterior or rear, the hinge is the dorsal or back/top region, and the bottom corresponds to the ventral or (as it were) underside/belly. However, as many scallop shells are more or less bilaterally symmetrical ("equivalved"), as well as symmetrical front/back ("equilateral"), determining which way
5175-479: The turbidity or clarity of the water, by detecting the movement of particulate matter in the water column. Scallops are mostly free-living and active, unlike the vast majority of bivalves, which are mostly slow-moving and infaunal. All scallops are thought to start out with a byssus , which attaches them to some form of substrate such as eelgrass when they are very young. Most species lose the byssus as they grow larger. A very few species go on to cement themselves to
5250-832: The use of common names. For example, the Australian Fish Names List or AFNS was compiled through a process involving work by taxonomic and seafood industry experts, drafted using the CAAB (Codes for Australian Aquatic Biota) taxon management system of the CSIRO , and including input through public and industry consultations by the Australian Fish Names Committee (AFNC). The AFNS has been an official Australian Standard since July 2007 and has existed in draft form (The Australian Fish Names List) since 2001. Seafood Services Australia (SSA) serve as
5325-424: The valves propels water with a strong force near the hinge via the velum, a curtain-like fold of the mantle that directs water expulsion around the hinge. Scallops swim in the direction of the valve opening unless the velum directs an abrupt change in course direction. Other species of scallops can be found on the ocean floor attached to objects by byssal threads. Byssal threads are strong, silky fibers extending from
5400-503: The water during mating season and fertilized ova sink to the bottom. After several weeks, the immature scallops hatch and the larvae, miniature transparent versions of the adults called "spat", drift in the plankton until settling to the bottom again (an event called spatfall) to grow, usually attaching by means of byssal threads. Some scallops, such as the Atlantic bay scallop Argopecten irradians , are short-lived, while others can live 20 years or more. Age can often be inferred from annuli ,
5475-512: The water. Spawning typically occurs in late summer and early autumn; spring spawning may also take place in the Mid-Atlantic Bight . The females of scallops are highly fecund, capable of producing hundreds of millions of eggs per year. Once an egg is fertilized, it is then planktonic, a collection of microorganisms that drift abundantly in fresh or salt water. Larvae stay in the water column for four to seven weeks before dissipating to
5550-476: The year. This phenomenon is due to lower protein levels in adductor muscles. The scallop family is unusual in that some members of the family are dioecious (males and females are separate), while others are simultaneous hermaphrodites (both sexes in the same individual), and a few are protoandrous hermaphrodites (males when young then switching to female). Female scallops have red roe and male scallops have white roe. Spermatozoa and ova are released freely into
5625-471: Was achieved when Waller's studies in 1986, 1991, and 1993 concluded evolutionary relationships between pectinid taxa based on hypothesized morphological synapomorphies, which previous classification systems of Pectinidae failed to do. He created three Pectinidae subfamilies: Camptonectinidae, Chlamydinae and Pectininae. The framework of its phylogeny shows that repeated life habit states derive from evolutionary convergence and parallelism. Studies have determined
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