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Crustacean nauplii


Phylum Arthropoda
Subphylum Crustacea


  • Earliest and most basic type of a crustacean larva is the nauplius.
  • Development in the 1st naupliar stage is minimal, with only 3 pairs of appendages present – the 1st antennae, the second antennae and the mandibles.
  • During successive moults, trunk segments and additional appendages are usually added.
  • There is no segmentation of the body and a single eye (naupliar eye) in the centre of the head is present.
  • Nauplii are often extremely abundant in plankton samples and are generally from copepods, but can occasionally be from barnacles.
  • Barnacle nauplii are easily distinguishable because they possess a pair of ‘horns’ at the front of the head (image 2).
  • It is very difficult to separate nauplii into species and often they are lumped together as a single group.