Sand collars are the characteristic egg masses of one family of sea snails, the moon snails, marine gastropod mollusks in the family Naticidae. These egg masses are often found washed up either whole, or sometimes in fragments, on sandy beaches where moon snails are living, either intertidally or subtidally.
When they are intact, sand collars are shaped rather like an old-fashioned detachable shirt or blouse collar (hence the name). The sand collar consists of sand grains cemented together by a gelatinous matrix, with the embedded eggs contained within the matrix. The collar is laid by the female moon snail, and the size of the sand collar gives an indication of the size of the adult female moon snail that laid it; larger species of moon snail lay larger sand collars.
A fresh sand collar feels stiff and yet flexible, as if it were made out of plastic. Each sand collar contains thousands of capsules, each one housing one or several live embryos. In species with planktonic development, these embryos hatch out as bilobed veligers. After the eggs hatch, the sand collar disintegrates.
Naticidae, common name moon snails or necklace shells, is a family of minute to large-sized predatory sea snails, marine gastropod molluscs in the clade Littorinimorpha. The shells of the species in this family are mostly globular in shape.
The Naticinae are a subfamily of medium to large-sized predatory sea snails, marine gastropod molluscs in the family Naticidae, the moon snails.
Tanea zelandica, common name the necklace shell or the New Zealand moon snail, is a species of medium-sized sea snail, a predatory marine gastropod mollusc in the Family Naticidae, the moon snails or necklace shells.
Tectonatica is a genus of sea snails, marine gastropod molluscs in the family Naticidae, the moon snails.
Neverita is a genus of medium-sized to large sea snails, marine gastropod molluscs in the family Naticidae, the moon snails
Neverita lewisii, common name Lewis's moon snail, is a species of large operculated sea snail. It is a predatory marine gastropod in the family Naticidae, the moon snails. Traditionally, this species was assigned to either the genus Lunatia, the genus Polinices or the genus Euspira. Recently, it was assigned to the genus Neverita based on molecular data.
Euspira catena, previously known as Natica catena, common name the large necklace shell, is a medium-sized species of predatory sea snail, a marine gastropod mollusc in the family Naticidae, the moon snails.
Neverita josephinia is a species of predatory sea snail, a marine gastropod mollusk in the family Naticidae, the moon shells.
Clea helena, as it is still often called, common name assassin snail, is a species of freshwater snail with an operculum, an aquatic gastropod in the family Nassariidae, most of which are marine.
Naticarius hebraeus is a species of predatory sea snail, a marine gastropod mollusk in the family Naticidae, the moon snails.
Amoria undulata, common name wavy volute, is a species of sea snail, a marine gastropod mollusk in the family Volutidae, the volutes.
Cymbiola nobilis is a species of sea snail, a marine gastropod mollusk in the family Volutidae, the volutes. The snail's shell is commonly collected in the sea shell trade, which has resulted in overharvesting of the snail.
Natica arachnoidea, common name : the spider moon snail, is a species of predatory sea snail, a marine gastropod mollusk in the family Naticidae, the moon snails.
Notocochlis dillwynii is a species of predatory sea snail, a marine gastropod mollusk in the family Naticidae, the moon snails.
Naticarius onca is a species of predatory sea snail, a marine gastropod mollusk in the family Naticidae, the moon snails.
Naticarius stercusmuscarum, the Fly-specked Moon Snail, is a species of predatory sea snail, a marine gastropod mollusk in the family Naticidae, the moon snails.
Tectonatica violacea, common name the violet moon snail, is a species of predatory sea snail, a marine gastropod mollusk in the family Naticidae, the moon snails.
Neverita duplicata, common name the shark eye, is a species of predatory sea snail, a marine gastropod mollusk in the family Naticidae, the moon snails.
Tanea areolata is a species of predatory sea snail, a marine gastropod mollusk in the family Naticidae, the moon snails.
Tectonatica sagraiana is a species of predatory sea snail, a marine gastropod mollusk in the family Naticidae, the moon snails.
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