Syntexis libocedrii, (also called the cedar wood wasp or incense-cedar wood wasp) is the only living species in the wood wasp family Anaxyelidae, within the Symphyta, though the family has an extensive Mesozoic fossil record.

[2] This species is thus a "living fossil".

It has the remarkable behavior of greatly favoring ovipositing in recently burnt incense-cedar (Calocedrus), red cedar (Thuja) or juniper (Juniperus).

The wood is often still smoldering while the wasp is laying its eggs, and the larvae develop in the wood.

[3] S. libocedrii occurs from the mountains of central California to southern British Columbia, but is very rarely seen, except by firefighters.