Crustacean larva stop after a single copepodid stage. Once the gonads develop, there are no further moults. Chalimus (plural chalimi) is a stage of development of a copepod parasite of fish, such as the salmon louse ("Lepeophtheirus salmonis"). "Chalimus" Burmeister, 1834 is also a synonym for "Lepeophtheirus" Nordmann, 1832. The single genus in the Facetotecta, "Hansenocaris", is only known from its larvae. They were first described by Christian Andreas Victor Hensen in 1887, and named "y-nauplia" by Hans Jacob Hansen, assuming them to be the larvae of barnacles. The adults are presumed to be parasites of other animals. Crustacean larva Crustaceans may
Greylag goose behaviour. Greylag goose The greylag goose ("Anser anser") is a species of large goose in the waterfowl family Anatidae and the type species of the genus "Anser". It has mottled and barred grey and white plumage and an orange beak and pink legs. A large bird, it measures between in length, with an average weight of . Its distribution is widespread, with birds from the north of its range in Europe and Asia migrating southwards to spend the winter in warmer places. It is the type species of the genus "Anser" and is the ancestor of the domestic goose, having