THE COMPETENCE OF KALOTERMES FLAVICOLLIS FABR. (ISOPTERA) PSEUDERGATES TO DIFFERENTIATE INTO SOLDIERS

SUMMARY Previous investigations carried out in our laboratory on Kalotermes flavicollis Fabr. had shown that the royal pair exerts a stimulatory action on pseudergate differentiation into soldiers, while the latter have an inhibitory influence on it (SPRINGHETTI, 1969). The present experiments have shown that the pseudergate moulting interval is of fairly variable duration, from 18 to 140 days, with a mean of about 70 days. Its average duration, however, is the same both in specimens differentiating into soldiers and in those undergoing a larval moult. Pseudergates display a rather short competence period for differentiation into soldiers during the second half of the moulting interval: possibly between the 45th and 60th day. Pseudergates are responsive only during their competence period, to the antagonistic stimuli exerted by the royals and soldiers respectively. The absence of soldiers prior to the 40th day does not elicit the differentiation of new soldiers (even in the presence of the reproductives);...