Changes in the free amino acid concentrations of the haemolymph during development in Orthetrum sabina (Drury) (Anisoptera: Libellulidae)

The total free amino acid concentration in the haemolymph is similar with a very narrow range of variation in the different larval instars as well as in the imago. The basic amino acids are found in higher quantities in the early larval instars and they decrease in the later instars to reach their minimum values in the imago. The reverse is the case with the acidic amino acids. The sulphurcontaining amino acids are totally absent in the adults while they are present in the larvae.