The thoracic segments have one ganglion on each side, which are connected into a pair, one pair per segment. This arrangement is also seen in the <answer>abdomen</answer> but only in the first eight segments. Many species of insects have reduced numbers of ganglia due to fusion or reduction. Some cockroaches have just six ganglia in the <answer>abdomen</answer>, whereas the wasp Vespa crabro has only two in the thorax and three in the <answer>abdomen</answer>. Some insects, like the house fly Musca domestica, have all the body ganglia fused into a single large thoracic ganglion.
What other location on an insect are ganglia located?
abdomen