Phagocytosis is not the same as killing the microbial cells. Microbes are secondarily killed after phagoccytosis. GRs and oenocytoids are attracted to sites of wounds, where they play major roles in coagulating hemolymph to stop bleedings. We know virtually nothing about the signalling process that is responsible for moving cells to wound sites. Another defense mechanism is nodule formation.
Nodules are aggregates of hemocytes that entrap invading microbes.
This is a particularly effective means of clearing the hemolymph, and it is considered to be of greater importance than phagocytosis in clearing large doses of bacteria. There appears to be a sequence of trapping by GRs, followed by aggregation by PLs. The precise sequence of events will remain a point of controversy. In addition to bacteria, viral polyhedrons, fungal spores and protozoans are taken up in nodules. When organisms or clumps of organisms are too big to be phagocytized or to form nodules, they may be encapsulated.