Platynereis

Platynereis
Larvae of Platynereis dumerilii
Scientific classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Annelida
Clade: Pleistoannelida
Subclass: Errantia
Order: Phyllodocida
Family: Nereididae
Subfamily: Nereidinae
Genus: Platynereis
Kinberg, 1865

Platynereis is a genus of marine annelid worms that belongs to the Nereididae, a family of errant polychaete worms.

The species Platynereis dumerilii is used in development biology to study development (embryogenesis), in particular because their embryos are largely transparent, and thus easy to follow. Apical organs such as this one are photosensitive which is a key component in their formation. They also have a common ancestor with cnidarians and bilaterians.