Nereididae

Nereis succinea

Nereids ( Nereididae ) are in zoology a family in the class of polychaete ( Polychaeta ).

Features

The length of Nereids varies from a few millimeters ( genus Micronereis ) up to over a meter long Alitta virens. The body is segmented, in adult specimens is 15 to several hundred segments. In living animals, the color ranges from transparent to brown or red with a variety of other color and pigment patterns. Eyes, if any, are formed as two pairs.

At the prostomium ( rounded at Micronereis, triangular or rectangular in Namanereidinae or inverted T- shaped), there are two anterior antennae (rarely singly or absent) and two ventral palpi. On fused with the first segment Peristomium there are two to four pairs of tentacles, also known as cirrus or cirrus clouds.

The eversible two-piece throat ( pharynx ) is equipped with a pair of jaws and usually with, often conical teeth.

Occurrence

Nereids colonize all substrates of the oceans. They come Litoral to Abyssal, but mainly in shallow water ahead. Some species, for example in the genus Hediste, can also be found in brackish water, the type Tylorrhynchus heterochaetus is an example of the Nereids live in fresh water.

System

Nereididae In the three subfamilies Gymnonereinae, Namanereidinae and Nereidinae more than 39 genera with about 535 species.

Types (selection)

  • Genus Nereis: Green Ragworm ( Nereis virens)
  • Ragworm ( Nereis diversicolor )
  • Brown Ragworm ( Nereis pelagica )

Other types:

Abyssal zone
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