3rd-5th instars seem to produce a secretion on the posterior end, which coats the last few terga and the cerci. It is sticky, and likely to be a predator repellent. Whenever the roach molts, the secretion is left behind on the shell. Adults and young nymphs do not seem to possess this, which I cannot make sense of
Contributed by Vespula vulgaris on 3 January, 2011 - 10:25am Last updated 3 January, 2011 - 1:25pm
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