Turritellidae
The case of a worm tower
The tower snails ( Turritellidae ) family belongs to the class of snails and after the recent systematics in the order of Sorbeoconcha, such as beach and snails ( Littorininae ) and Grübchenschnecken ( Lacuninae ). Previously they were placed in the order today obsolete Mesogastropoda (Medium Screw ). Tower worm is also a commonly used name for non-related species of snails and families with tower-like cases ( such as for the Turridae family).
Features
Many of the species in this family are characterized by an elongated, tapered shape of the housing with a large number of turns of, thereby also explains the name Tower snails. Which are on the head sensor are relatively long, the foot is rather short. The seam (the area between the windings ) is pronounced, a hub is not present. The top of some species up to 19 turns are usually less arched than the lower ones.
Way of life
This present in sea snails burrow into the sea floor and feed mostly by one spin of small food particles. Strudler are animals that - in contrast to the filter feeders - active flagella or cilia produce by a stream of water from small food particles filtering. The genus Turritella generates the flow of water, for example by means of the edge of the lid (operculum ) located bristles. All species are dioecious, hermaphrodite not occur. Some species are ovoviviparous, their offspring hatch already in the womb of the mother.
Species
Is known primarily living in the North Sea and the Mediterranean Common Tower Snail ( Turritella communis). The Great Tower Snail ( Turritella terebra ) with a size of up to 18 cm occurs in the Indo-Pacific region. First fossils of this family are known for Devon.
Fossil localities Fund
The Turritellidae play a major role in the chronological determination of rock strata by fossils ( biostratigraphy ) in paleontology.
- A significant fossil locality Turritellen is the Erminger Turritellenplatte. It represents a massive accumulation of tower shells ( Turritella turris Basterot ) from the Lower Miocene represents the deposit was around 18.5 million years ago (Lower Ottnangium ) formed under shallow marine coastal conditions. The site is located in Ulm- Ermingen ( Hochsträß ) and has been described in several paleontological work.