There is a small group of insects (family Mantispidae) known as mantisflies, so-called because of their resemblance to small praying mantises. Climaciella brunnea (pictured) is the most commonly encountered mantisfly in the Northeast. Not only does it have the grasping forelegs of a praying mantis, but it also mimics a paper wasp.
A newly hatched Climaciella brunnea larva attaches itself to an arachnid host, preferably a wolf spider. It lives off the blood of the spider until the spider lays eggs, and then the larva positions itself so that it gets wrapped up in the spider’s egg sac along with the eggs. Once inside the sac the larva feeds on the eggs until it pupates. The adult mantisfly emerges and preys on other insects, often those visiting flowers, and consumes nectar and sap as well. Although they lay an enormous number of eggs, mantisflies are relatively rare.
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