iNereidae
Eunereis longissima
Scientific classification
Kingdom: Animalia Phylum: Annelida Class: Polychaeta Order: Aciculata Suborder: Phyllodocida Family: Nereidae Fauchald 1977
Genera
Nereis Platynereis Namalycastis Namanereis Eunereis Hediste Neanthes Perinereis Australonereis Laeonereis Dendronereides Olganereis Nicon Rullierinereis Leptonereis Sinonereis Tylonereis Tylorrhynchus Ceratocephale Gymnonereis Tambalagamia Micronereides Ceratonereis Solomononereis Unanereis Lycastopsis Cheilonereis Websterinereis For other uses, see Scientific classification (disambiguation). ... Phyla Subregnum Parazoa Porifera Subregnum Eumetazoa Placozoa Orthonectida Rhombozoa Radiata (unranked) Ctenophora Cnidaria Bilateria (unranked) Acoelomorpha Myxozoa Superphylum Deuterostomia Chordata Hemichordata Echinodermata Chaetognatha Xenoturbellida Superphylum Ecdysozoa Kinorhyncha Loricifera Priapulida Nematoda Nematomorpha Onychophora Tardigrada Arthropoda Superphylum Platyzoa Platyhelminthes Gastrotricha Rotifera Acanthocephala Gnathostomulida Micrognathozoa Cycliophora Superphylum Lophotrochozoa Sipuncula Nemertea Phoronida Ectoprocta Bryozoa... Classes and subclasses Class Polychaeta (paraphyletic?) Class Clitellata    Oligochaeta - Earthworms and others    Acanthobdellida    Branchiobdellida    Hirudinea - Leeches Class Myzostomida Class Archiannelida (polyphyletic) Class Echiura *Some authors consider the subclasses under Clitellata to be classes The annelids, collectively called Annelida, are a large phylum of animals, comprising the segmented worms, with about... Orders Amphinomida Capitellida Chaetopterida Cirratulida Cossurida Ctenodrillidae Eunicida Flabelligerida Magelonida Myzostomida Nerillida Opheliida Orbiniida Orweniida Phyllodocida Pisionidae Polygordiida Protodrilida Psammodrilidae Sabellida Spionida Spintheridae Sternaspida Terebellida The Polychaeta or Polychaetes are a class of annelid worms, generally marine, with a pair of fleshy protrusions on each body segment called parapodia that... Look up genus in Wiktionary, the free dictionary. ... The genus Nereis is one of many categorized within the class Polychaete. ...

Nereidae (sometimes also spelled Nereididae) are a family of polychaete worms. It contains about mostly marine 500 species grouped into 42 genera. They may be commonly called ragworms or clam worms. Orders Amphinomida Capitellida Chaetopterida Cirratulida Cossurida Ctenodrillidae Eunicida Flabelligerida Magelonida Myzostomida Nerillida Opheliida Orbiniida Orweniida Phyllodocida Pisionidae Polygordiida Protodrilida Psammodrilidae Sabellida Spionida Spintheridae Sternaspida Terebellida The Polychaeta or Polychaetes are a class of annelid worms, generally marine, with a pair of fleshy protrusions on each body segment called parapodia that... It has been suggested that Trivial name be merged into this article or section. ...

Characteristics

The prostomium of Nereidae bears a pair of palps that are differentiated into 2 units, the proximal unit is much larger than the distal unit. Parapodia are mostly biramous (only the first two pairs are uniramous). Peristomium fused with the first body segment, with usually 2 pairs of tentacular cirri. The first body segment with 1-2 pairs tentacular cirri without aciculae. Compound setae present. Notopodia are distinct (rarely reduced), usually with more flattened lobes, notosetae compound falcigers and/or spinigers (rarely notosetae absent). They have 2 prostomial antennae (absent in Micronereis). Pharynx, when everted, clearly consists of 2 portions, with a pair of strong jaws on the distal portion and usually with conical teeth on one or more areas of both portions. Most genera have no gills (if present, they are usually branched and arise on mid-anterior segments of body). The larval body consists of four segments. Prostomium (sometimes also called acron) is the first body segment in annelids worms. ... Male European garden spider with swollen pedipalps Pedipalps are a pair of feelers on a spiders face. ... Parapodia (almost feet) are paired lateral outgrowths, bearing bristles known as chaetae. ... Cirrus can refer to: a type of cloud, cirrus cloud a car produced by DaimlerChrysler, Chrysler Cirrus a German rocket, cirrus (rocket) a trance music group, Cirrus (music group) an interbank network (ATM network) by MasterCard, Cirrus (interbank network) a British aircraft engine company, Cirrus Engine an aircraft company, Cirrus... Acicula: The chitinous support rods within parapodia found in the Class Polychaeta. ... A seta is a stiff hair, wierd, culy, things bristle, or bristle-like process or part of an organism. ... Antennae (singular antenna), are the paired appendages connecting to the first (and in crustaceans also to the second) segment of the head of the members of all subphyla of the arthropods except Chelicerata. ... The pharynx (plural: pharynges) is the part of the neck and throat situated immediately posterior to the mouth and nasal cavity, and cranial to the esophagus, larynx, and trachea. ... In aquatic organisms, gills are a respiratory organ for the extraction of oxygen from water and for the excretion of carbon dioxide. ... A larva (Latin; plural larvae) is a juvenile form of animal with indirect development, undergoing metamorphosis (for example, insects or amphibians). ...

Systematics

Nereidae are currently considered a monophyletic taxon. Their closest neighbours in polychaete phylogenetic tree are Chrysopetalidae and Hesionidae (the superfamily Nereidoidea). In phylogenetics, a group is monophyletic (Greek: of one stem) if all organisms in that group are known to have developed from a common ancestral form, and all descendants of that form are included in the group. ... It has been suggested that Evolutionary tree be merged into this article or section. ...

Nereidae are divided into 42 genera, but the relationships between them are as yet unclear. The family contains traditionally three subfamilies - Namanereidinae, Gymnonereinae and Nereidinae.

Ecology

Nereidae are predominantly marine organisms that may occasionally swim upstream to rivers and even climb to land (for example Lycastopsis catarractarum). They are commonly found in all water depths, foraging in seaweeds, hiding under rocks or burrowing in sand or mud. Nereids are mainly omnivorous but many are active carnivores. Omnivores are organisms that consume both plants and animals. ... This tigers sharp teeth and strong jaws are the classical physical traits expected from carnivorous mammalian predators A carnivore (IPA: ), meaning meat eater (Latin carne meaning flesh and vorare meaning to devour), is an animal that eats a diet consisting mainly of meat, whether it comes from live animals...

References

• Santos et al, 2006[1]
• A Key to Families of Polychaetes[2]
• The City University of Hong kong page on Nereidae[3]
• [4]