California’s Butterflies

Parasites

Butterflies have many parasites.  Most of the diversity is in the Hymenoptera or Wasp Order.  Some of these wasps, such as the Trichogramma, are extremely small.  These tiny wasps parasitize butterfly eggs. For example, as many as 20 mature wasps can emerge from a single swallowtail egg.  Other wasps parasitize larvae and can hatch in a later instar or even later from the chrysalis.

 

There are many types of larval parasites, but many of them are in the closely related Ichneumonidae and Braconidae.  These parasites can be solitary or gregarious.  Sometimes many parasite larvae can emerge from a single larva.

 

There are also many pupal parasites.  Many of these parasites were oviposited upon the larva even though they come out of the chrysalis.  There are also many species that are hyperparasites, or parasites of parasites.  Diversity from the chrysalis is the greatest.  Some pupae will produce a hundred or more tiny parasites.

 

Most of the remaining parasites are Tachinid flies.  Although there are a fair number of species of these flies, many of them are very similar to one another.