Image Credit: Martin Cooper
Spiny-flies (Tachinidae) – parasites of herbivores. Though there are only about a dozen genera of Tachinidae with especially long mouthparts, all the genera in the family are known to frequent flowers for nectar and mating. There are thousands of different tachinid flies in North America and hundreds in the PNW; they are poorly-studied but it is possible to identify them to genus. The vast majority of tachinids are caterpillar parasites, but a few very distinctive genera parasitize stink-bugs (Pentatomidae).
Typical spiny-flies are very abundant flower-visitors. The black Tachinus (subgenus Nowickia) on the left is bumblebee-sized; Peleteria (center) is honeybee-sized; and the odd-ball Gymnosoma on the right is bottle-fly sized (the several genera, mentioned above that are stink-bug parasites often have very few of the spiny hairs. The distinguishing morphological character for the Tachinidae is the presence of a bulbous protrusion near the rear of the thorax (note it on the Peleteria).