Byssus filaments are created by certain kinds of marine and freshwater bivalve mollusks, which use the byssus to attach themselves to rocks, substrates, or seabeds. In edible mussels, the inedible byssus is commonly known as the "beard", and is removed before cooking. Byssus often refers to the long, fine, silky threads secreted by the large Mediterranean pen shell, Pinna nobilis. The byssus threads from this Pinna species can be up to 6 cm in length and have historically been made into cloth.
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The animals attach themselves to a solid substrate using a byssus.
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Knitted glove made of sea silk, from Taranto, Italy, probably from the late 19th century Pinna nobilis shell and byssus The extreme fineness of the byssus thread Sea silk is an extremely fine, rare, and valuable fabric that is made from the long silky filaments or byssus secreted by a gland in the foot of pen shells (in particular Pinna nobilis). The byssus is used by the clam to attach itself to the sea bed. Sea silk was produced in the Mediterranean region from the large marine bivalve mollusc Pinna nobilis until early in the 20th century. The shell, which is sometimes almost a metre long, adheres itself to rocks with a tuft of very strong thin fibres, pointed end down, in the intertidal zone.
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The Greek text of the (196 BCE) Rosetta Stone records that Ptolemy V reduced taxes on priests, including one paid in byssus cloth. This is thought to be fine linen cloth,Translation of the Greek section of the Rosetta Stone. not sea silk. In Ancient Egyptian burial customs, byssus was used to wrap mummies; this was also linen and not sea silk.
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When they have passed through several developmental stages they settle to the seabed, undergo metamorphosis and attach themselves with byssus threads as miniature adults.
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Its shape differs depending on the region it inhabits. Like all pen shells, it is relatively fragile to pollution and shell damage. It attaches itself to rocks using a strong byssus composed of many silk-like threads which used to be made into cloth. The animal secretes these fibres from its byssus gland; they consist of keratin and other proteins and may be as long as .
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Some attach to the substrate using a byssus. The foot is reduced. The mantle margins are not fused. Gills are usually large and assist in feeding.
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The inner surface of the shell is blue and faintly pearly. Like other mytilids, the animal is attached to the substrate with a very strong and elastic byssus.
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Adults develop a large shell that adheres to the substrate by its byssus, a tuft of long, tough filaments that protrude from a hole next to the hinge.
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See editorial comment for Byssus coerulea at . See the Species Fungorum entry for Terana coerulea at . Krieglsteiner GJ. (1983). "The blue corticium Pulcherricium caeruleum and its occurrence in Europe".
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The Dreissenidae are a family of small freshwater mussels, aquatic bivalve molluscs. They attach themselves to stones or to any other hard surface using a byssus. The shells of these bivalves are shaped somewhat like those of true mussels, and they also attach themselves to a hard substrate using a byssus, however this group is not at all closely related to true mussels, being more closely related to the venus clams (Veneridae).
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Some bivalves, such as oysters and most scallops, are unable to extend their foot and in them, these muscles are absent. Other paired muscles control the siphons and the byssus.
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It prefers soft substrates and surrounds its shell in a dense mass of byssus. One of several negative impacts of this invasive species is that it has a detrimental effect on eelgrass.
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B-Byssus Cloth Production-(Tax) remitted. (Past Byssus owed, Remitted) C-5 Grain Bushels on temple aroura lands remitted. Likewise the temple aroura Vineyards. :#Endowments to Temples of Apis and Mnevis A-Plus the animal burials B-Provisions for the animal temples, Festivals conducted, Burnt Offerings, (animals) for slaughter, drink offerings (libations), and all things (everything) "customary", and the best for temples, and everything, large quantities, of Egypt, (provided) "according to what [is] in the laws"Budge, (1989), p. 150.
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Mytilids include the well-known edible sea mussels. A common feature of the shells of mussels is an asymmetrical shell which has a thick, adherent periostracum. The animals attach themselves to a solid substrate using a byssus.
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M. modiolus is found growing on hard substrates including shells and stones and the byssus threads of other mussels. Survival rates of young individuals are low but by the time they reach about 4 cm long, at an age of 4 years, individuals are too large and tough to be predated upon by starfish such as Asterias rubens, the whelk Buccinum undatum and crabs. Juveniles growing on byssus threads are more likely to survive than free living individuals and this results in the formation of cold-water reefs of mussels.Modiolus modiolus UK Marine SAC's Project.
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Hindwing undersides of both genders distinctly show paler, yellowish fulvous veins. Identification of the species is considered difficult, with individuals of Euphyes dion, Euphyes byssus and probably other skippers that sometimes lack normal hindwing patterns closely resembling Euphyes berryi.
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It is a larval host to the Arogos skipper, Byssus skipper, cobweb skipper, common wood nymph, Delaware skipper, and the dusted skipper.The Xerces Society (2016), Gardening for Butterflies: How You Can Attract and Protect Beautiful, Beneficial Insects, Timber Press.
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Carditamera affinis is a filter feeder, straining nutrients from sea water that it pumps through its body. It is sessile as an adult, attaching itself to rocks and within crevices using a byssus. These animals can live as long as 17.25 years.
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Pinna noblis shell & byssus. Shell. These pen shells can reach a length of about . They are characterized by thin, elongated, wedge-shaped, and almost triangular shells with long, toothless edges. The surface of the shells shows radial ribs over their entire length.
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The outline is mytiliform with a terminal umbo, but the shape is very variable and specimens may be highly expanded posteriorly, occasionally curved; sometimes almost cylindrical with the beaks being sub-terminal. The animal is attached to the substrate by thick byssus.
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This species is native to the southern coasts of the Sea of Japan, in Western Sakhalin, Hokkaido and Honshu Island. This low- boreal species lives attached by a byssus under rocks. It prefers shallow near-bottom waters in intertidal areas at depths of .
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It occurs from the low water mark to depths of down to 800 m. It lives on hard substrates, often attached with byssus, for instance in mussel beds or nestling among kelp holdfasts, or hiding in rock crevices and also boring itself into soft rocks.
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Many species of mussels secrete byssus threads to anchor themselves to surfaces, with families including the Arcidae, Mytilidae, Anomiidae, Pinnidae, Pectinidae, Dreissenidae, and Unionidae. When a mussel's foot encounters a crevice, it creates a vacuum chamber by forcing out the air and arching up, similar to a plumber's plunger unclogging a drain. The byssus, which is made of keratin, quinone-tanned proteins (polyphenolic proteins), and other proteins, is spewed into this chamber in liquid form, and bubbles into a sticky foam. By curling its foot into a tube and pumping the foam, the mussel produces sticky threads about the size of a human hair.
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Long before the connection was made between the nonlichenized agaric fruitbodies and the lichenized thalli, botanists and lichenologists named the asexual lichen thalli of Lichenomphalia species several times in a number of genera. Linnaeus in 1753 described the lichen thallus of L. umbellifera as an 'alga' named Byssus botryoides while simultaneously including the fruitbodies of L. umbellifera within his concept of Agaricus umbelliferus, the basionym for the name L. umbellifera. Byssus botryoides is the type species of the now officially rejected generic names Phytoconis and Botrydina. Acharius in 1810 described the thalli of L. hudsoniana as a lichen, Endocarpon viride, which is the type of another officially rejected name, Coriscium.
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During metamorphosis, the veliger sheds its velum and, depending on species, may secrete an attachment structure called a byssus that anchors it to the substratum. Some species spend considerable time searching for an ideal habitat before metamorphosing, but others may settle on the nearest suitable substrate.
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Over time, the walnut packaging and beliefs about byssus cloth were conflated. (151–152.) The cloth attracts clothes moths, the larvae of which will eat it. In addition, Pinna nobilis is also sometimes gathered for its flesh (as food) and occasionally has pearls of fair quality.
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Anomiids have extremely thin, translucent, paper-like shells. There is often a hole in the lower shell, caused by growth of the shell around the byssus. The shell follows the shape of the object it lies on - usually a rock or a large shell of another creature.
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Blue mussels often form aggregations, where they attach to each other using byssus threads. These are collagenous protein strands used for attachment. The type of aggregation depends on population densities. When densities are low, for example in mussel fields – short-lived mussel populations – clumped distribution patterns are seen.
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It can flap its gills slightly to create a hollow in which to settle. In shallow waters it is usually attached by byssus threads to hard surfaces so as not to be swept away by water movement. At greater depths it is usually free living.Adamussium colbecki (Smith, 1902) Antarctic Field Guide.
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The interior of the shell is white with a broad pallial line, large anterior adductor muscle scar and smaller posterior adductor muscle scar. The body is deep orange and the mantle is unfrilled. The shell is firmly attached to the substrate by byssus threads.Horse mussel - Modiolus modiolus Marine Life Information Network.
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Said valves are almost symmetrical, toothless, and transparent on the ends. Their color is usually reddish brown. The spiny fan-mussel lives with the pointed anterior end of its shell vertically anchored to rock or firm sediment by numerous byssus threads. The rear edge of the shell is rounded and free.
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Cuttlefish of the order Sepiida Pinna nobilis shell and byssus List of mollusc orders illustrates the 97 orders in the phylum Mollusca, the largest marine animal phylum. 85,000 extant species are described,Chapman, A.D. (2009). Numbers of Living Species in Australia and the World, 2nd edition. Australian Biological Resources Study, Canberra.
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Spondylus varius in Mayotte. The many species of Spondylus vary considerably in appearance. They are grouped in the same superfamily as the scallops. They are not closely related to true oysters (family Ostreidae); however, they do share some habits such as cementing themselves to rocks rather than attaching themselves by a byssus.
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The mussel then varnishes the threads with another protein, resulting in an adhesive. Byssus is a remarkable adhesive, one that is neither degraded nor deformed by water as synthetic adhesives are. This property has spurred genetic engineers to insert mussel DNA into yeast cells for translating the genes into the appropriate proteins.
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The earliest usage of the English name sea silk remains uncertain, but the Oxford English Dictionary defines sea-silkworm as "a bivalve mollusc of the genus Pinna."OED2, under Sea, n. 23 (d). Alexander Serov's 1863 opera Judith includes an aria "I shall don my robe of byssus" (Я оденусь в виссон).
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Once the pediveliger is fully developed, its foot extends and makes contact with substrate. The initial contact with the substrate is loose. If the substrate is suitable, the larva will metamorphoses into the juvenile form, plantigrade, and attach byssus threads. The mussel will remain in that state until reaching 1-1.5mm in length.
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In fact, the 16th century art historian Giorgio Vasari wrote in his book that the German artist Albert Durer was painting in watercolours on byssus silk and sent his portrait as a gift to Raphael in honor of his work from the second edition of the works of Giorgio Vasari La Giuntina.
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Atrina seminuda, is an inhabitant endobentic, usually secured by a strong byssus secreted by the animal in rocks and gravel substrate in areas of high energy. Associated with the outer faces of the leaflets of Atrina seminuda usually inhabit a range of fouling organisms among them being common gastropod mollusks, bivalves and chitons.
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Sometimes this reticulation is worn away by friction with nearby rocks, and the shell can be smooth. There is a large gape between the valves along the bottom, ventral, side of the shell through which the byssus anchors the animal to a rocky substrate. Barbatia reeveana may be 82mm long, 45mm high, and 29mm deep.
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The hairy mussel is found around the coasts of Tasmania and southern and eastern Australia as far north as Cairns. It lives on exposed reefs and among rocks and seaweed in the intertidal and subtidal zone, attaching itself to hard surfaces using its byssus threads.Mytilidae: Trichomya hirsuta (Lamarck, 1819) ('hairy mussel') Molluscs of Tasmania. Retrieved 2012-05-21.
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Lasaea rubra is native to the eastern Atlantic Ocean where its range extends from Norway through the North Sea to the Canary Islands and the Mediterranean Sea. It is found in the intertidal zone on rocky shores, lodged in crevices, in tufts of lichen or among the holdfasts ad fronds of seaweed, attached by byssus threads.
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A few fine ridges radiate from the umbone and there is a sculpting of concentric growth rings. The lower valve has a hole or notch in it through which byssus threads pass which attach it to a hard surface, usually a branch, leaf or aerial root of a mangrove tree.Mangrove jingle shell: Enigmonia aenigmatica Wildsingapore. Retrieved 2012-04-23.
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Pinna is distinguished from its sibling genus Atrina by the presence of a sulcus dividing the nacreous region of the valves, and the positioning of the adductor scar on the dorsal side of shells. These bivalves most commonly stand point-first in the sea bottom in which they live, anchored by a net of byssus threads.
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Manoppello (Abruzzese: ') is a comune in Abruzzo, in the province of Pescara, south-eastern Italy. Holy Face image. It is famous for having a church which contains an image on a thin byssus veil, a sudarium, known as the Holy Face of Manoppello and which has been reputed to be identical to the Veil of Veronica. Veil of Veronica.
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The shell's interior has a pale-blue sheen. The mussel has a large mobile foot which it uses to climb vertically should it be covered by sediments. It also produces byssus to help it attach to its substrate. Perna canaliculus and Perna perna are two similar species, native to the waters of New Zealand and Africa respectively.
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This species is found along the Atlantic coast of North America, ranging from North Carolina to the West Indies and Bermuda.Abbott, R.T. & Morris, P.A. A Field Guide to Shells: Atlantic and Gulf Coasts and the West Indies. New York: Houghton Mifflin, 1995. 8. It attaches itself to rocks or other hard substrates in shallow water with byssus threads.
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Freshwater zebra mussels and their relatives in the family Dreissenidae are not related to previously mentioned groups, even though they resemble many Mytilus species in shape, and live attached to rocks and other hard surfaces in a similar manner, using a byssus. They are classified with the Heterodonta, the taxonomic group which includes most of the bivalves commonly referred to as "clams".
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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 to 80% in shell height and quadrupled size in meat weight, and reach commercial size at about four to five years of age. The lifespans of some scallops have been known to extend over 20 years.
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Then it dilates the tip of its foot, retracts the adductor muscles to close the shell, shortens its foot and draws itself downwards. This series of actions is repeated to dig deeper. Other bivalves, such as mussels, attach themselves to hard surfaces using tough byssus threads made of keratin and proteins. They are more exposed to attack by predators than the burrowing bivalves.
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Molluscs within this genus are characterized by elongated, wedge-shaped shells, distinguished from the genus Pinna by the lack of any grooves in the nacreous lining of the shell, and by the central positioning of the adductor scar. As with other pen shells (Pinnidae) they commonly stand point-first in the sea bottom in which they live, anchored by net of byssus threads.
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The spiny scallop anchors itself to the substrate with a few byssus threads. It is unclear what the purpose of these is but they may serve to help orient the scallop with regard to the current for optimal feeding. Another possibility is that they may angle the scallop ready for a quick getaway. They are easily broken when the scallop starts to swim.
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This allows shelter until more food is required, when foraging resumes. If waves are large or there is an excessive risk of water loss the dog whelk will remain inactive in sheltered locations for long periods. Mussels have developed a defensive strategy of tethering and immobilising with byssus threads any dog whelks invading their beds, leading to the whelks' starvation.
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The Atlantic winged oyster is often found attached to the stems of gorgonian corals by strong byssus threads. It often has algae and other organisms growing on the shell which make it well camouflaged. It is a filter feeder and is reproductively active all year round. The spat abundance varies and has four peaks in the period November to March.
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Species of the genus Limopsis are among the few suspension feeding deep-sea bivalves, and are absent from the continental shelf. They are relatively small, byssate (i.e. attached to the sea floor by strong threads, or byssus), and, while the viscera are reduced, there is a comparatively thick shell. Differences between species are usually defined by minor differences in gill and palp structure.
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This species is the origin of sea silk, which was made from the byssus of the animal.Hill, John E. (2009) Through the Jade Gate to Rome: A Study of the Silk Routes during the Later Han Dynasty, 1st to 2nd centuries CE. John E. Hill. BookSurge, Charleston, South Carolina. . See Section 12 plus "Appendix B – Sea Silk". pp. 468–476.
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During further larval stages they develop siphons and gills. When they are ready to undergo metamorphosis, they search for suitable timber on which to settle. They seem to be able to detect rotting wood and are able to swim towards it when they are close enough. Each one then crawls around until it finds a suitable location where it attaches itself with a byssus thread.
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The valves are sculpted by fine concentric lines which show the annual growth rings. The anterior ear is considerably longer than the posterior ear. The right anterior ear has a notch to accommodate the byssus, which anchors the shell in place, and small teeth on the lower edge. The interior surface of the shell is glossy and is often the same colour as the exterior.
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The fecundity of the species increases with size, a 40-millimeter female producing up to 2.4 million eggs. The larva, a trochophore, begins to develop a shell 2 days after it hatches from the egg. Within 2 weeks it settles onto a hard substrate, attaches to it with a byssus, and eventually burrows into the sediment. Its maximum life span is about 13 to 14 years.
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This means that the correct species name is coerulea, not caerulea. Both names are found frequently in the literature. Strangely enough, Lamarck's name Byssus has now come to be applied to a plant genus - a fundamentally different organism. In 1763 Michel Adanson had devised the genus name Terana for similar crust fungi and in 1891 Otto Kuntze included coerulea in that genus to create the modern name.
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This species lives with the narrow half of its shell anchored in the sediment, but the large part of the fragile shell protrudes from the sea floor. Thus, unfortunately it is vulnerable to damage by fishing trawlers. The shells are anchored to the sand by fine gold-coloured silk produced by special glands. This silk or byssus are fine threads which historically was used to make special royal fabrics.
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Similar passages appear in other texts such as the Bowuzhi (c. 290 CE), These aquatic people supposedly spun a type of raw silk called jiaoxiao "mermaid silk" or jiaonujuan "mermaid woman's silk". Schafer equates this with sea silk, the rare fabric woven from byssus filaments produced by Pinna "pen shell" mollusks. Chinese myths also recorded this "silk" coming from shuiyang 水羊 "water sheep" or shuican 蠶水 "water silkworm".
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The California mussel prefers the high salinity, low sediment conditions found on open rocky coasts. However, they do not colonize bare rock easily, instead preferring the shelter of pre-existing mussels and their biological filaments. Mussels attach themselves to the hard surfaces using their thread-like byssus. Given the right circumstances, California mussels can grow up to 200 mm (8 inches) in length and may live for more than 20 years.
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The labial palps finally funnel the food into the mouth, where digestion begins. Marine mussels are usually found clumping together on wave-washed rocks, each attached to the rock by its byssus. The clumping habit helps hold the mussels firm against the force of the waves. At low tide mussels in the middle of a clump will undergo less water loss because of water capture by the other mussels.
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The International Code of Botanical Nomenclature states that names of fungi adopted by Fries in Systema Mycologicum vols. 1–3 are sanctioned, that is, they are conserved against earlier homonyms and competing synonyms. This means that the name Hypochnus rubrocinctum has priority over Byssus sanguinea. The type material of H. rubrocinctum was examined by Christian Gottfried Ehrenberg in Berlin; it has since been destroyed, probably during the Second World War.
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Bathymodiolus thermophilus is a very large mussel with a dark brown periostracum, growing to a length of about . It is attached to rocks on the seabed by byssus threads but it is able to detach itself and move to a different location. It is sometimes very abundant, having been recorded at densities of up to 300 individuals per square metre (270 per square yard).Hydrothermal vents Deep Ocean.
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In other taxa, alternate layers of calcite and aragonite are laid down. The ligament and byssus, if calcified, are composed of aragonite. The outermost layer of the shell is the periostracum, a skin- like layer which is composed of a conchiolin. The periostracum is secreted in the groove between the outer and middle layers of the mantle, and is usually olive or brown in colour and easily abraded.
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Lister's tree oyster is an irregular, fan-shaped shell growing to about long. Each valve is a pale brown colour with whitish rays radiating from the umbo, the raised hump that is the first part of the shell to form when the animal is a juvenile. There are numerous sculptured concentric rings on the outside surface. It is attached to a hard substrate by byssus threads and often occurs in clusters.
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There are many examples in nature where soft tissue and hard surfaces are connected by a mechanical gradient to improve the fracture and impact resistance. Examples include mussels that connect to hard rocks by the mussel byssus which connects back to the soft muscle of the foot.Harrington, M. J.; Waite, J. H., How Nature Modulates a Fiber's Mechanical Properties: Mechanically Distinct Fibers Drawn from Natural Mesogenic Block Copolymer Variants. Adv Mater 2009, 21 (4), 440-+.
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During the rest of development in the brooding chamber the valves complete and a straight-hinged veliger larva grows. When the spat (larvae) leave the brooding chamber, they begin to develop an eye spot and a foot. They then migrate to hard surfaces (usually old oyster shells) where they attach by secreting a "glue" like substance from their byssus gland. Ostrea lurida spat swim with their foot superior to the rest of their body.
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The fertilized egg develops into a free-swimming veliger which feeds on smaller plankton. At roughly three weeks after fertilization, the veliger becomes a pediveliger. At this stage of development, the animal is approximately 0.2 mm in diameter and has a foot which allows it to crawl on the seabed. In response to some unknown environmental cue, the pediveliger attaches itself to the seabed with a byssus and grows into adulthood at that spot.
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The flat tree oyster has two thin, irregularly shaped valves joined by a long straight hinge. The exterior is sculptured by a large number of rough, concentric rings with loose flakes and varies in colour from a pale brownish olive to a purplish black. The nacre on the inside is lustrous and cream coloured shaded with purplish brown. The shell is attached to the substrate by a byssus thread and grows to about in length.
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The shells of bivalves in this family are fragile and have a long and triangular shape, and in life the pointed end is anchored in sediment using a byssus. The shells have a thin but highly iridescent inner layer of nacre in the part of the shell near the umbos (the pointed end). The family Pinnidae includes the fan shell, Atrina fragilis, and Pinna nobilis, the source of sea silk. Some species are also fished for their food value.
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Like other scallops, this species is a filter feeder, drawing water through its gills and removing the edible fragments. It changes sex several times during the course of its development, becoming a male when fully mature. It is attached by byssus threads when young but may be detached when older. It is often overgrown by the holdfasts of the seaweeds among which it lives, and sponges such as Halichondria panicea may also grow over the shell.
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Behaviorally, cockles live buried in sediment, whereas scallops either are free-living and will swim into the water column to avoid a predator, or in some cases live attached by a byssus to a substrate. The mantle has three apertures (inhalant, exhalant, and pedal) for siphoning water and for the foot to protrude. Cockles typically burrow using the foot, and feed by filtering plankton from the surrounding water. Cockles are capable of "jumping" by bending and straightening the foot.
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Buttons have traditionally been made from a variety of freshwater and marine shells. At first they were used decoratively rather than as fasteners and the earliest known example dates back five thousand years and was found at Mohenjo-daro in the Indus Valley. Sea silk is a fine fabric woven from the byssus threads of bivalves, particularly the pen shell (Pinna nobilis). It used to be produced in the Mediterranean region where these shells are endemic.
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The sakos covered the head entirely like a sack or bag; it was made of various materials, such as silk, byssus, and wool.Comp. Aristoph. Tltcsin. 257. Some times, at least among the Romans, a bladder was used to answer the same purpose.Mart. viii. 33. 19. The mitra was a broad band of cloth of different colours, which was wound round the hair, and was worn in various ways. It was originally an Eastern head-dress, and may, therefore, be compared to the modern turban.
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There is no substantiated evidence connecting the cloth with Rome or the crucifixion. However, some have observed bits of glass embedded in the cloth, suggesting a connection between it and its former glass container in St. Peter's, reputed to have been smashed open when the cloth was stolen. Nevertheless, the cloth has received much publicity in recent years and Pope Benedict XVI visited the veil on 1 September 2006. Likewise, Pfeiffer's claims as to the purported impossibility of painting on byssus cloth have been conclusively debunked.
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It is used to pull the animal through the substrate (typically sand, gravel, or silt) in which it lies partially buried. It does this by repeatedly advancing the foot through the substrate, expanding the end so it serves as an anchor, and then pulling the rest of the animal with its shell forward. It also serves as a fleshy anchor when the animal is stationary. In marine mussels, the foot is smaller, tongue-like in shape, with a groove on the ventral surface which is continuous with the byssus pit.
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When they settle, metamorphosis takes place and the juveniles attach themselves with byssus threads, often attaching these to the upper valves of scallops, and remain attached for 3 to 5 years. While attached to the adult shell, the juveniles benefit from food particles in the fine detritus thrown up into the water column by movements of the adult. While studying the sizes and growth rates of adults, researchers came to realize that there were gaps in their records which were due to the fact that, in some years, no juveniles had survived.
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After spawning the animals undergo period of recovery of the gonad before they spawn again. Fertilization of the gametes is external and either sperm or oocytes can be released into the water column first. Since the larval stage of Pecten maximus is relatively long, up to a month, the potential for dispersal is quite high, even smaller adults can use the byssus to drift too. However, in at least some populations, genetic studies show that there is little contribution from more distant populations and that these populations probably sustain themselves.
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Pinctada fucata has two valves connected by a long straight hinge. The length of the shell is slightly greater than its width, and the latter is about 85% of the length of the hinge. The right valve is flatter than the left and there are hinge teeth in both valves. The anterior ear is larger than that in other members of the genus and there is a slit-like notch for the byssus threads to pass through at the junction of the ear and the rest of the shell.
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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, which is a collection of microorganisms that drift abundantly in fresh or salt water. Larvae stay in the water column for the next four to seven weeks before dissipating to the ocean floor, where they attach themselves to objects through byssus threads.
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Examinations of these deposits in Peru has provided a means of dating long past El Niño events because of the disruption these caused to bivalve shell growth. Invertebrate predators include crabs, starfish and octopuses. Crabs crack the shells with their pincers and starfish use their water vascular system to force the valves apart and then insert part of their stomach between the valves to digest the bivalve's body. It has been found experimentally that both crabs and starfish preferred molluscs that are attached by byssus threads to ones that are cemented to the substrate.
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Anomia simplex is a species of bivalve mollusk in which each valve is responsible for a set of specific tasks. Moreover, the upper valve is convex and movable, often contributing to the filter-feeding quality of Anomia simplex which is achieved through their ciliated gills. On the other hand, the lower valve is concave and matches the curvature and irregularities of the hard substrate it has attached. Threads or finger-like projections, called byssus, are known for attaching themselves to an object, which protrude from the top of the lower valve through a extruded hole.
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This species, which for a member of the corticioid fungi is relatively easy to identify, was first described in 1779 by Jean-Baptiste Lamarck, who is best known for proposing an early theory of evolution. Lamarck used the name Byssus caerulea, and various other designations were subsequently employed, until in 1828 Fries classified it as Thelephora violascens variety coerulea. According to rule 13.1.d. of the International Code of Botanical Nomenclature, valid publication of fungal names is treated as beginning with Fries's publication of "Systema Mycologicum" in 1821 and following years.
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In this pit, a viscous secretion is exuded, entering the groove and hardening gradually upon contact with sea water. This forms extremely tough, strong, elastic, byssal threads that secure the mussel to its substrate allowing it to remain sessile in areas of high flow. The byssal thread is also sometimes used by mussels as a defensive measure, to tether predatory molluscs, such as dog whelks, that invade mussel beds, immobilising them and thus starving them to death. In cooking, the byssus of the mussel is known as the "beard" and is removed during preparation, often after cooking when the mussel has opened.
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Drawing of zebra mussel, showing the byssus Research on natural enemies, both in Europe and North America, has focused on predators, particularly birds (36 species) and fish (15 and 38 species eating veligers and attached mussels, respectively). The vast majority of the organisms that are natural enemies in Europe are not present in North America. Ecologically similar species do exist, but these species are unlikely to be able to eliminate those mussels already established and have a limited role in their control. Crayfish could have a significant impact on the densities of 1- to 5-mm-long zebra mussels.
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He notes, "This is, perhaps, the Byssus, a clothstuff woven up to the present time by the Mediterranean coast, especially in Southern Italy, from the thread-like excrescences of several sea-shells, (especially Pinna nobilis)."Tr. Bretschneider 1871, p. 24 The early 6th century CE Shuyiji ("Records of Strange Things") mentions silk woven by Jiaoren, "jiao-dragon people", which Edward H. Schafer identifies as sea silk. > In the midst of the South Sea are the houses of the kău people who dwell in > the water like fish, but have not given up weaving at the loom.
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Near the hinge of the shell is the umbo, often a rounded, knob- like protuberance usually surrounding the beak. The umbo - generally, and the beak - specifically, represent the oldest portion of the shell, with extra material gradually being laid down along the margins on the opposite sides. The hinge point or line is the dorsal region of the shell, and the lower, curved margin is the ventral region. The anterior or front of the shell is where the byssus (when present) and foot are located, and the posterior of the shell is where the siphons are located.
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The Atlantic paper mussel is attached to the seabed and other nearby mussels by means of byssus threads secreted by a gland in the foot. In some areas it is very common and in the Nassau River estuary in Florida in 1993 was recorded at a density of 3325 per square metre (309 per sq ft). It is a filter feeder and draws water into the mantle cavity, passes it over its gills where the plankton on which it feeds adhere to mucus-covered cilia, and expels the water from the posterior end of the shell. Breeding takes place between October and January.
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Protobranchia is a subclass of bivalve molluscs. It contains the extant orders Nuculanida, Nuculida, and Solemyida. These are deep water clams of a small and primitive order with a taxodont hinge (composed of many similar, small teeth), generally with a central ligament pit, large labial palps which are used in deposit feeding and the gills used only for respiration, the anterior and posterior adductor muscles are nearly equal in size, a foot which is divided sagittally and longitudinally with papillate margins. The foot in Protobranchia clams is without a true byssus gland, although they frequently have a nonhomologous byssal gland in the heel.
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Tyrian purple, made from the ink glands of murex shells, "fetched its weight in silver" in the fourth century BC, according to Theopompus.The fourth-century BC historian Theopompus, cited by Athenaeus (12:526) around 200 BC ; according to The discovery of large numbers of Murex shells on Crete suggests the Minoans may have pioneered the extraction of "imperial purple" during the Middle Minoan period in the 20th–18th centuries BC, centuries before the Tyrians. Sea silk is a fine, rare, and valuable fabric produced from the long silky threads (byssus) secreted by several bivalve molluscs, particularly Pinna nobilis, to attach themselves to the sea bed.Webster's Third New International Dictionary (Unabridged) 1976.
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When young they are attached to the substrate by a byssus but mature animals are capable of swimming by the opening and rapid closing of the valves. The adductor muscle which is used to close and open the valves is very large and powerful. The foot is a finger-like organ, which spins the byssal threads, which pass through the byssal notch on the ears. The margin of the mantle has two layers the inner layer is finely fringed while the outer is lined with long tentacles with two series totalling 30-36 dark blue or green simple eyes or ocelli in two rows at their base.
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In Jules Verne's 1870 novel 20,000 Leagues Under the Sea, the crew of the Nautilus wear clothes made of byssus (alternately translated as "seashell tissue" or "fan-mussel fabric"). Pinna nobilis has become threatened with extinction, partly due to overfishing, the decline in seagrass fields, and pollution. As it has declined so dramatically, the once small but vibrant sea silk industry has almost disappeared, and the art is now preserved only by a few women on the island of Sant'Antioco near Sardinia. Chiara Vigo claimed on various media to be the sole person living today to master the art of working with byssusMaeder, Hänggi, and Wunderlin 2004, pp. 68–71.
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The small family of proteins that are sometimes referred to as polyphenolic proteins are produced by some marine invertebrates like the blue mussel, Mytilus edulis by some algae', and by the polychaete Phragmatopoma californica. These proteins contain a high level of a post-translationally modified—oxidized—form of tyrosine, L-3,4-dihydroxyphenylalanine (levodopa, L-DOPA) as well as the disulfide (oxidized) form of cysteine (cystine). In the zebra mussel (Dreissena polymorpha), two such proteins, Dpfp-1 and Dpfp-2, localize in the juncture between byssus threads and adhesive plaque. The presence of these proteins appear, generally, to contribute to stiffening of the materials functioning as bioadhesives.
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The lower right portion of this image shows a Venerupis senegalensis with a distinct pallial sinus on the viewer's right side/ animal's right valve which points towards the animal's posterior The oldest point of a bivalve shell is called the beak, and the raised area around it is known as the umbo (plural umbones). The hinge area is the dorsum or back of the shell. The lower, curved margin is the ventral side. The anterior or front of the shell is where the byssus and foot are located (if the animal has these structures) and the posterior or back of the shell is where the siphon is located (again, if present— the scallops, for example, do not have siphons).
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In the 18th century, Sardinian lore claimed the wild goats of Tavolara had gold teeth.McGrigor, Charles Rhoderick (1866), Garibaldi at Home: Notes of a Visit to Caprera, pp 49-51 The goat herds were moved to Sardinia when the NATO station was built and there are no longer any goats on the island. The critically endangered monk seal had a breeding colony here until the 1960s. Once the home of a thriving lobster industry, Tavolara now attracts divers who come to view the coral, sponges, sea anemones, bottlenose dolphins, and even a few specimens of Pinna nobilis, the rare giant clam whose byssus fibers were formerly used in the manufacture of sea silk for royal garments.
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With the umbones/ hinge uppermost and with the anterior edge of the animal towards the viewer's left, the valve facing the viewer is the left valve and the opposing valve the right. In all molluscs, the mantle forms a thin membrane that covers the animal's body and extends out from it in flaps or lobes. In bivalves, the mantle lobes secrete the valves, and the mantle crest secretes the whole hinge mechanism consisting of ligament, byssus threads (where present), and teeth. Visible on the inside of most empty bivalve valves is a shiny curved line that runs more or less parallel to the outer margin of the shell and often connects the two adductor muscle scars (if the animal had two adductor muscles).
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The process of anchoring to a hard substrate can be described as metamorphosis or settling, including a larval stage and ultimately leading to an anchored bivalve mollusk configuration. Firstly, Anomia simplex larvae maturing and approaching metamorphosis drop to the bottom of shallow waters, and begin crawling through the use of a strong foot in order to find a hard substrate. Once the suitable substrate is found, the larvae bind to the structure through byssus filaments, which will then be calcified meaning a permanent bond is formed. Lastly, anomia simplex will end metamorphosis by the development of well-structured gills, which aid in food absorption by the mollusk and will be the primary source of nutrients for the remainder of the lifetime of Anomia simplex.
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A few groups of bivalves are active swimmers like the scallops; many bivalves live buried in soft sediments (are infaunal) and can actively move around using their muscular foot; some bivalves such as blue mussels attach themselves to hard substrates using a byssus; other groups of bivalves (such as oysters, thorny oysters, jewel boxes, kitten's paws, jingle shells, etc.) cement their lower valve to a hard substrate (using shell material as cement) and this fixes them permanently in place. In many species of cemented bivalves (for example the jewel boxes), the lower valve is more deeply cupped than the upper valve, which tends to be rather flat. In some groups of cemented bivalves the lower or cemented valve is the left valve, in others it is the right valve.
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