Incubation is very short, it takes only a few hours, in some species even shorter, after which the females lay tiny, capsule-like egg sacs on rocky areas of the sea bed where the eggs enjoy more protection than on the open sea bed. Male and female nassa snails look identical and there is very little information about their reproductive habits, but it seems that mating takes place with one individual climbing on another one, inserting a tube-like organ into a hole on the body of the other. ![]() They are shy animals, too, spending a lot of time buried in the substrate with only the long, tube-like, scent-sensitive siphon sticking out from the sand or the mud, waiting to catch the smell of food – when they do catch the smell of food, they rise from the sand quickly to pursue their meal, behavior that gives these creature the nickname zombie snails. They are known as very efficient cleaners of the sea bed, consuming carrion such as decaying fish or crabs. ![]() These snails are scavengers, but unlike other species of marine snails, they don’t eat algae, feeding exclusively on the detritus they find while roaming on the sea bed. Unlike other marine snails, nassa snails are quite fast, moving along effortlessly with the help of a muscular pedal flap. The snail has a long siphon protruding from the shell and it also has long eye stalks, but when disturbed, the entire body, including the siphon and the horns, withdraws into the shell that becomes instantly sealed with a protective cover called an operculum. It is also textured – nassarius originally means wicker basket in Latin, and the texture of the snail’s shell features striations that resemble woven baskets, indeed. The spiral shell of the snail is tall and oval-shaped, resembling an olive pit, and usually has a grey, light brown or tan color. Nassa snails vary in size from very small to medium, usually growing to 1-3 cm in length. They are common in all the seas and oceans around the world – wherever there are sandy or muddy, flat areas on the substrate, these little creatures will appear and thrive. The genus of marine invertebrates comprises over 800 species. A typical egg string may contain 45 eggs and be 6 cm (2.4 in) long.Nassarius snails – also called nassa mud snails – are small, but extremely efficient and hardy scavengers. After this, the snail moves forward slightly and repeats the process, eventually producing a series of flattened capsules that overlap each other giving a shingled effect. This process takes about ten minutes, during which time the snail's body and shell oscillate from side to side. The egg mass passes along this fold and the pedal gland is used to cement the egg capsule to the leaf blade. First it cleans a portion of leaf blade with its radula, then it forms a fold in its foot connecting its genital pore with its mucous pedal gland. Nassarius fossatus lays its eggs on eelgrass or some other solid object on the surface of the mudflats. Its reaction is either to crawl away rapidly, rocking its shell from side to side, or do a spectacular flip or series of flips, catapulting itself with its muscular foot. fossatus can similarly detect the approach of a predator such as the starfish Pisaster brevispinus. A dead fish in a creek has been found to attract snails from as far away as 30 m (98 ft) downstream. It is able to detect odors with its long proboscis and when it finds something edible, it winds its foot round it and rasps at the surface with its radula. When the tide is out it crawls across the surface of the mud leaving a distinctive trail. Nassarius fossatus is a predator and scavenger. It is found intertidally on mudflats and also subtidally on sandy and muddy substrates to a depth of about 18 m (59 ft). Its range extends from Vancouver Island to Baja California. This species is native to the coasts adjoining the northeastern Pacific Ocean. The rest of the shell surface is grayish-brown or ashy gray and is matte in appearance. The columella (the central supporting structure around which the shell is coiled) is thickened at the aperture and is usually orange. The lip of the aperture is finely toothed at the margin and slightly ridged inside. There is a siphonal notch at the edge of the aperture through which a breathing siphon can be extended. The aperture is less than half the diameter of the shell and can be closed by a horny operculum. The surface of the shell is sculpted with fine axial ribs and spiral ridges, giving it a basket-like texture. There is a distinctive transverse groove on the lowermost portion of the body whorl. The width of the body whorl of the spirally coiled shell is about half the total length of the shell and there are about six further whorls of diminishing size. ![]() This is one of the largest mud snails in the genus and has a robust shell that can reach nearly 5 cm (2 in) long.
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