|Monarch parasitoid from WOLF School|
|Ready to pupate at WOLF school|
While several of the Monarchs emerged, one chrysalis shriveled and tiny black insects emerged, a mere 3 mm in length. The students kept the container covered with plastic wrap until we could collect them. By microscopic photographs we were able to identify the parasites and here begins the tale of the Chalcidid wasps.
These are not the wasps I knew as a child. For one thing they are tiny, 2.5 to 9 mm long, (0.1 to 0.34 inches for those allergic to the metric system). They don't build nests or dig holes for their young but instead place their eggs on the larvae of lepidoptera or diptera (true flies), or less commonly other insect species. Their larvae develop within the victim, their birth announcing the death of their host.
|Ventral view of parasitoid wasp|
Chalcididae wasps are common parasitoids of other species. However in the case of Monarchs they may also directly attack the pupa. According to Monarchprogram.org, "Tiny wasps from the family Chalcididae unsuccessfully penetrate the pupa casing therefore leaving a small hole. The pupa begins to turn dark and dies."
|Pteromalid Wasp - Marci Hess|