| Limaria fragilis | |
|---|---|
 | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Bivalvia |
| Order: | Limida |
| Family: | Limidae |
| Genus: | Limaria |
| Species: | L. fragilis |
| Binomial name | |
| Limaria fragilis | |
| Synonyms [1] | |
| |
Limaria fragilis, the fragile file clam, is a species of bivalve mollusc in the family Limidae. It is found in shallow waters in the Indian and Pacific Oceans and has the ability to swim.
The fragile file clam has a pair of hinged, thin, asymmetric white valves and a red mantle with a fringe of long tapering pink and grey banded tentacles at its edge. Also around the margin of the mantle are a row of tiny eyespots that can detect light and shade, and may alert the animal to the approach of a predator. [2]
The fragile file clam is widely distributed in the Indo-Pacific region. Its range includes the Philippines, the Marshall Islands, the Cook Islands, Western Australia, the Chagos Archipelago, Madagascar and the Red Sea. [1] It often conceals itself in crevices or under stones with just its tentacles protruding. [2]
The fragile file clam is a protandrous hermaphrodite. Juveniles start life as males and change sex to females as they grow. Fragile file clams have the ability to emit flashes of bioluminescent light, though why they do this is unclear. [2]
The fragile file clam can swim slowly and continuously for about 5 minutes at a time. [3] It does this by opening and closing its valves and expelling water in a stream from either side of the hinge, a form of jet propulsion. In an aquarium, the animal flits around knocking into other objects. [2] It uses its mantle tentacles in an oar-like fashion when swimming. Sometimes it sheds the longest tentacles and can still swim effectively without them, increasing the frequency of valve clapping to maintain speed. [4] The detached tentacles secrete a noxious substance and continue to writhe after they are severed which may distract aggressors. [5]
It was originally thought that the energy for swimming was supplied aerobically through respiration with little input from anaerobic glycolysis and arginine phosphate. Further study showed that this was not the case. There was a high level of arginine kinase and certain other enzymes in the adductor muscles which was indicative of the conversion of arginine phosphate for energy production. Up to 23% of the ATP used for energy transfer was supplied in this way while the animal was swimming. [3]
Bivalvia or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of aquatic molluscs that have laterally compressed soft bodies enclosed by a calcified exoskeleton consisting of a hinged pair of half-shells known as valves. As a group, bivalves have no head and lack some typical molluscan organs such as the radula and the odontophore. Their gills have evolved into ctenidia, specialised organs for feeding and breathing.
The maxima clam, also known as the small giant clam, is a species of bivalve mollusc found throughout the Indo-Pacific region.
Ctenoides scaber, the flame scallop or rough fileclam, is a species of saltwater clam, a marine bivalve mollusc in the family Limidae. Despite their common name, flame scallops are not closely related to true scallops.
Atrina fragilis, the fan mussel, is a species of large saltwater clam, a marine bivalve mollusc in the family Pinnidae, the pen shells.
Limaria hians, the flame shell, is a species of small saltwater clam, a marine bivalve mollusc in the family Limidae. This species is native to the northeastern Atlantic Ocean.
Tridacna crocea, the boring clam, crocus clam, crocea clam or saffron-coloured clam, is a species of bivalve in the family Cardiidae. It is native to the Indo-Pacific region. It is occasionally found in the aquarium trade where it is often simply referred to as crocea.
Freshwater bivalves are molluscs of the order Bivalvia that inhabit freshwater ecosystems. They are one of the two main groups of freshwater molluscs, along with freshwater snails.
The Limidae or file shells are members of the only family of bivalve molluscs in the order Limida. The family includes 130 living species, assigned to 10 genera. Widely distributed in all seas from shallow to deep waters, the species are usually epifaunal or nestling, with many species building byssal nests for protection. The majority of species are capable of irregular swimming by waving their long mantle tentacles.
Lima is a genus of file shells or file clams, marine bivalve molluscs in the family Limidae, the file shells, within the subclass Pteriomorphia.
Limaria, the file shells or file clams, is a genus of marine bivalve molluscs in the family Limidae.
A valve is each articulating part of the shell of a mollusc or another multi-shelled animal such as brachiopods and some crustaceans. Each part is known as a valve or in the case of chitons, a "plate". Members of two classes of molluscs, the Bivalvia (clams) and the Polyplacophora (chitons), have valves.
A bivalve shell is the enveloping exoskeleton or shell of a bivalve mollusc, composed of two hinged halves or valves. The two half-shells, called the "right valve" and "left valve", are joined by a ligament and usually articulate with one another using structures known as "teeth" which are situated along the hinge line. In many bivalve shells, the two valves are symmetrical along the hinge line — when truly symmetrical, such an animal is said to be equivalved; if the valves vary from each other in size or shape, inequivalved. If symmetrical front-to-back, the valves are said to be equilateral, and are otherwise considered inequilateral.
Brachiopods, phylum Brachiopoda, are a phylum of trochozoan animals that have hard "valves" (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, while the front can be opened for feeding or closed for protection. Two major categories are traditionally recognized, articulate and inarticulate brachiopods. The word "articulate" is used to describe the tooth-and-groove structures of the valve-hinge which is present in the articulate group, and absent from the inarticulate group. This is the leading diagnostic skeletal feature, by which the two main groups can be readily distinguished as fossils. Articulate brachiopods have toothed hinges and simple, vertically oriented opening and closing muscles. Conversely, inarticulate brachiopods have weak, untoothed hinges and a more complex system of vertical and oblique (diagonal) muscles used to keep the two valves aligned. In many brachiopods, a stalk-like pedicle projects from an opening near the hinge of one of the valves, known as the pedicle or ventral valve. The pedicle, when present, keeps the animal anchored to the seabed but clear of sediment which would obstruct the opening.
Chlamys hastata, the spear scallop, spiny scallop or swimming scallop, is a species of bivalve mollusc in the family Pectinidae found on the west coast of North America from the Gulf of Alaska to San Diego, California. A limited number of these scallops are harvested by divers or by narrow trawls off the west coast of Canada.
Lima lima, or the spiny fileclam, is a species of bivalve mollusc in the family Limidae.
Fabulina fabula, the bean-like tellin, is a species of marine bivalve mollusc in the family Tellinidae. It is found off the coasts of northwest Europe, where it lives buried in sandy sediments.
Tellina tenuis, the thin tellin, is a species of marine bivalve mollusc in the family Tellinidae. It is found off the coasts of northwest Europe and in the Mediterranean Sea, where it lives buried in sandy sediments.
Lutraria lutraria is a species of large marine bivalve mollusc in the family Mactridae. Its common names include the otter shell and the common otter shell. It occurs in coastal regions of the north east Atlantic Ocean where it lives buried in the sand.
Crassadoma is a genus of rock scallops, marine bivalve molluscs in the family Pectinidae. It is monotypic, the only species being Crassadoma gigantea, the rock scallop, giant rock scallop or purple-hinge rock scallop. Although the small juveniles are free-swimming, they soon become sessile, and are cemented to the substrate. These scallops occur in the eastern Pacific Ocean.
A prodissoconch is an embryonic or larval shell which is present in the larva of a bivalve mollusk. The prodissoconch is often but not always smooth, and has no growth lines. It is sometimes still present and visible in the adult shell, if there has been no erosion of the shell in that area.