Nereis

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Nereis
Eunereis longissima
Eunereis longissima
Scientific classification
Kingdom: Animalia
Phylum: Annelida
Class: Polychaeta
Order: Phyllodocida
Family: Nereidae
Genus: Nereis
Linnaeus, 1758
Species

about 120

Nereis is a genus of polychaete worms in the family Nereidae. It comprises many species, most of which are marine, including the sandworm (Nereis virens) and the common clam worm (Nereis succinea). Nereis possess setae and parapodia for locomotion. They may have two types of setae, which are found on the parapodia. Acicular setae provide support. Locomotor chaetae are for crawling, and are the bristles that are visible on the polchaeta's exterior

Nereis are osmoconformers.

Nereids are dioecious and they release their haploid gametes into the water medium, a process called spawning. Moreover, Nereids upon fertilisation and mitotic divisions of the zygote, a larval stage forms which is similar to that of Molluscs, ie a Trocophore larva.