Polymorphic diversity in salivary and haemolymph proteins and digestive physiology of assassin bug Rhynocoris marginatus (Fab.) (Het., Reduviidae)

Rhynocoris marginatus (Fab.) occurs in three morphs viz. (i) niger (black c onnexivum) (ii) sanguineous (red connexivum) and (iii) nigrosanguineous (bl ack and red banded connexivum). The salivary protein (mug/mg wet weight of salivary gland complex), and haemolymph protein (mug/100 mul) were higher i n niger morph than in nigrosanguineous and sanguineous morphs. Endopeptidas e (trypsin) activity of homogenate of salivary gland complex (SGC) of niger morph was also higher. It was significantly lower in the sanguineous morph . Endopeptidase activity was found to be uniformly meagre in the anterior m idgut (AMG) and in the posterior midgut (PMG) in all the three morphs. The exopeptidase (aminopeptidase) activity was also found to be negligible in S GC in all the three morphs. Niger morph showed a significantly higher activ ity of exopeptidase in AMG and PMG than the other two morphs.