Some species of bagworms have small perpendicular larval structures that are superficially similar to the frass plugs of ambrosia beetles. The frass plugs are rather crumbly, whereas bagworm "bags" are rather tough.
Ambrosia beetles (Xyleborus spp. and Platypus parallelus) burrow into the trunks of presumably stressed palms where they feed on the ambrosia fungi that they cultivate.
Ambrosia beetles are cosmopolitan in distribution.