The zoea (zoeal pl. The European lobster ( Homarus gammarus) (possibly referred as Crayfish) is a large European clawed Lobster. ) is a free-swimming larval stage of crustaceans. A larva ( Latin; plural larvae) is a juvenile form of Animal with indirect development, undergoing Metamorphosis (for example Structure of crustaceans As Arthropods crustaceans have a stiff Exoskeleton, which must be shed to allow the animal to grow ( Ecdysis or molting It follows the nauplius stage, and precedes the post-larva. A nauplius (plural nauplii) is the first Larva of animals classified as Crustaceans (subphylum of Arthropoda) Zoea larvae swim with their thoracic appendages (as opposed to nauplii, which use cephalic appendages, and megalopa which use abdominal appendages for swimming). An appendage in the broadest sense is an additional or subsidiary part existing on or added to something which can generally still function if the appendage has never existed or It often has spikes on its carapace which may assist these small organisms in maintaining directional swimming ^[1]. A carapace is a dorsal section of an Exoskeleton or shell in a number of animal groups In many decapods, due to their accelerated development, the zoea is the first larval stage. The decapods or Decapoda ( literally means "ten footed") are an order of Crustaceans within the class Malacostraca, including many In some cases the zoea stage is followed by the mysis stage and in others by the megalopa stage, depending on the crustacean group involved.

References

1. ^ Weldon, W. F. R. (1889). Note on the function of the spines of the Crustacean zoea. Journal of the Marine Biological Association of the United Kingdom 1 (2): 169–172.  

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