Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Tachinid from Malacosoma tigris caterpillar

Tachinid from Malacosoma tigris caterpillar
Middle Bear, Catalinas, Pima County, Arizona, USA
June 6, 2012

Moved from Tachinidae.

Tachinidae: Exoristini
Tachinidae: Exoristini probably either Exorista or Chetogena, can't tell from this view

Which characters do you need to see?

Face and eyes
According to the key in Manual of Nearctic Diptera, Chetogena has "eye covered with conspicuous dense hairs" and "facial ridge with row of erect, widely and evenly spaced, stout bristles, usually on lower two-third or more". (Plus a wing character that is visible here.) Exorista has "eye apparently bare", and facial ridge with short decumbent bristles descending to middle of facial ridge.