''Solecurtus strigilatus'', also known as the rosy razor clam, is a species of saltwater

clam Clam is a common name for several kinds of bivalve mollusc. The word is often applied only to those that are deemed edible and live as infauna, spending most of their lives halfway buried in the sand of the sea floor or riverbeds. Clams h ...

, a marine

bivalve Bivalvia () or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class (biology), class of aquatic animal, aquatic molluscs (marine and freshwater) that have laterally compressed soft bodies enclosed b ...

mollusc Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum ...

in the family

Solecurtidae The Solecurtidae are a family of saltwater clams, marine bivalve molluscs in the order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorizat ...

. This mollusc is a

suspension feeder Filter feeders are aquatic animals that acquire nutrients by feeding on organic matters, food particles or smaller organisms (bacteria, microalgae and zooplanktons) suspended in water, typically by having the water pass over or through a spec ...

and can burrow with great rapidity to escape predators. It is an unusual bivalve in that its shell valves are too small to contain all the soft tissue, and the animal is unable to retreat into its shell.

Description

The valves of the rosy razor clam are relatively small, thin and finely sculptured. At the anterior end of the animal there is a strong, protruding foot. At the posterior end, is the large mantle sac containing the gills; when relaxed, it protrudes and is twice the length of the valves, but it can be contracted back between the valves. Posterior to this are the two robust, contractile siphons. The maximum length of the shell is .

Right and left valve of the same specimen: File:Solecurtus strigilatus 01.jpg, Right valve File:Solecurtus strigilatus 02.jpg, Left valve

Distribution

The rosy razor clam occurs in the Mediterranean Sea and the adjoining part of the Atlantic Ocean. It is present from the lower shore down to the shallow

sublittoral zone The neritic zone (or sublittoral zone) is the relatively shallow part of the ocean above the drop-off of the continental shelf, approximately in depth. From the point of view of marine biology it forms a relatively stable and well-illuminated ...

Behaviour and ecology

The species lives immersed in soft sediment, usually medium-grade sand. The burrow is J-shaped and has a

mucus Mucus (, ) is a slippery aqueous secretion produced by, and covering, mucous membranes. It is typically produced from cells found in mucous glands, although it may also originate from mixed glands, which contain both Serous fluid, serous and muc ...

lining. The clam has two siphons which it can extend to the surface in order to feed, but when not feeding it burrows further into the sediment, often living under the sand surface. Many clams are

detritivore Detritivores (also known as detrivores, detritophages, detritus feeders or detritus eaters) are heterotrophs that obtain nutrients by consuming detritus (decomposing plant and animal parts as well as feces). There are many kinds of invertebrates, ...

s, consuming decomposing organic matter they find in their environment, but this clam is a

filter feeder Filter feeders are aquatic animals that acquire nutrients by feeding on organic matters, food particles or smaller organisms (bacteria, microalgae and zooplanktons) suspended in water, typically by having the water pass over or through a s ...

, drawing water in through one siphon, removing the edible particles and exhaling the water through the other siphon. It can dig through the sand with great rapidity, and any attempt by humans to dig it out results in it descending diagonally, even deeper into the sediment. In an apparent attempt to distract predators, the tips of the two siphons can be shed, and these pulsate as they drift in the water column. The ends of the siphons can be regenerated. The presence of this clam in the sediment is evidenced by two circular holes each wide and apart, through which the siphons can be projected. Digging is a five-phase process; the mantle sac and siphons fill with water and the foot remains contracted; the siphons close, forcing water into the mantle sac while the foot unfolds; the mantle sac contracts, directing a jet of water in front of the foot; the foot is pushed into the loosened sediment; the tip of the foot expands to provide an anchor and the body is drawn down, ready to start the next cycle.

References

{{Taxonbar, from=Q14363598 Solecurtidae Molluscs described in 1758 Molluscs of the Atlantic Ocean Molluscs of the Mediterranean Sea Taxa named by Carl Linnaeus