RESUMO
Five types of haemocytes have been identified in the haemolymph of Spilostethus hospes. Their morphology and micrometric measurements have been provided. Changes in the total and differential haemocyte population [total haemocyte count (THC) and differtial haemocyte count (DHC)] as well as in the absolute number of haemocytes in circulation have been assessed in relation to eclosion, sex and mating. The haemogram profile was studied prior to and immediately after eclosion and also prior to and after copulation. Though the THC was not significantly different immediately before and after eclosion, there was a significant increase in total count prior to copulation. Mated females registered an increase in total count but there was no appreciable change in the mated males. Granulocytes were the most abundant of the haemocyte types in both the sexes and mating caused a significant increase in the plasmatocyte count in females. Changes in the blood volume as well as the mitotic activity of the haemocytes is also discussed.