Naupliar development of Parastenhelia megarostrum (Copepoda: Harpacticoida), and its bearing on phylogenetic relationships

Abstract

The six nauplius stages of Parastenhelia megarostrum are described in detail and significant autapomorphies are revealed, viz. loss of seta on the mandibular basis of NI and NII, the large size of the basis and exopod of the mandible, the simplification of the mandibular endopod seta and the armature of the antennal endopod claw. Larval, juvenile and adult characters confirm Lang's earlier positioning (1948) of the Parastenheliidae in close phyletic proximity to the Thalestridae.

Keywords :

• Copepoda
• Harpacticoida
• Parastenheliidae
• Thalestridae
• relationships
• larval development
• New Zealand