Nassarius?qsrc=3044

Nassarius

A live individual of Nassarius tiarula
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
(unranked):	clade Caenogastropoda clade Hypsogastropoda clade Neogastropoda
Superfamily:	Buccinoidea
Family:	Nassariidae
Subfamily:	Nassariinae
Genus:	Nassarius Dumeril, 1806
Species
See text
Synonyms
Arcularia Link, 1807 Alectrion Montfort, 1810 Hima Leach in Gray, 1852 Tritonella Adams, 1852 Mirua Marwick, 1931 Reticunassa Iredale, 1936 Telasco H. & A. Adams, 1853 Tarazeuxis Iredale, 1936 Zeuxis H. & A. Adams, 1853 Venassa Martens, 1881 Glabrinassa Shuto, 1969 Bathynassa Ladd, 1976 Profundinassa Thiele, 1929 Varicinassa Habe, 1946 Cryptonassarius Cernohorsky, 1975

Nassarius, common name nassa mud snails (USA) or dog whelks (UK), is a genus of minute to medium-sized sea snails, marine gastropod molluscs in the family Nassariidae.

These snails are scavengers.

Table of Contents

1	Ecology
	1.1	Distribution and habitat
	1.2	Life habits
2	Shell description
3	Anatomy
4	Human use
	4.1	Archeology
	4.2	Modern uses
5	Taxonomy
6	Species
7	References
8	External links

Ecology

Distribution and habitat

Species within this genus are found worldwide. These snails usually live on mud flats or sand flats, intertidally or subtidally.

Life habits

Most Nassarius species are very active scavengers, feeding on such things as dead fish, etc. They often burrow into marine substrates and then wait with only their siphon protruding, until they smell nearby food.

Shell description

The shells of species in this genus have a relatively high spire and a siphonal notch.

Anatomy

A live individual of a Nassarius species on an aquarium wall, reflected in the glass

The animal has a long siphon.

Human use

Archeology

Several beads made from Nassarius gibbosulus shells are thought to be the earliest known forms of personal adornment, or even jewelry. Two shell beads found in Skhul Cave on the slopes of Mount Carmel, Israel are thought to be 100,000 years old, whilst another found at Oued Djebbana, Algeria is believed to be 90,000 years old. A further group of pierced shells, some with red ochre, has been recovered from the Aterian levels at Grotte des Pigeons, Taforalt, Morocco; these Nassarius gibbosulus beads have been securely dated to about 82,000 years ago.^[1]

All these examples predate several 75,000 year old Nassarius kraussianus beads which were found at Blombos Cave, South Africa (including some colored with red ochre). These beads had previously been thought to be the oldest examples of jewelry.^[2]

Modern uses

Nassarius vibex is a species which is often selected for marine aquaria. It is often confused with Nassarius obsoletus, a cooler water snail less suited to tropical marine aquarium temperatures. In aquaria, the Nassarius is considered nearly indispensable for keeping sand beds clean and healthy, as these snails tend to burrow and plow through the upper layer in a conch-like fashion, keeping algae and detritus from building up visibly on the surface.

The shells of various species of Nassarius are popular with shell collectors, and are sometimes used in jewelry and other forms of decoration.

Taxonomy

The genus Nassarius has traditionally been subdivided into several subgenera, based on differences in shell morphology, especially the sculpture : Aciculina, Alectrion, Allanassa, Nassodonta, Niotha, Plicarcularia, Profundinassa, Pygmaeonassa, Telasco, and Zeuxis. However, this division is difficult to define, resulting in much confusion. Even phylogenetic analysis shows that the division into these subgenera appears to be uncertain and unreliable. There seem to be two groups within the genus Nassarius with the closest relationship between the subgenera Zeuxis and Telasco. Even the species within the subgenus Plicarcularia do not belong to a single clade. In the end, the molecular phylogeny did not match the previous morphological phylogeny. ^[3]