Thread subject: Diptera.info :: Fly and botanical ID (USA)
Posted by syncrasy on 23-06-2010 22:04
#1
What type of fly is this and what are the yellow objects stuck to its claws? Observed in a small prairie in northern Illinois (USA).
Click to enlarge:
Posted by Tony Irwin on 24-06-2010 12:56
#2
The fly is a
Pollenia female (Calliphoridae) and the yellow things on its feet look like pollenia! (or they might be very sticky seeds? - but no idea what from)
Posted by pwalter on 24-06-2010 14:03
#3
An orchid pollinarium?
Posted by syncrasy on 24-06-2010 14:48
#4
Ahh... pollinia! I had never heard of that term before. I did some more research and believe these yellow objects are Milkweed pollinia, or more precisely, Milkweed pollinaria. (Milkweed is prevalent in northern USA prairies.) According to the
Milkweed Flowers Web site, the "whole upside-down-V-shaped structure with its pollinarium gland and two pollinia is called a pollinarium."
Thank you!
Posted by syncrasy on 24-06-2010 14:51
#5
Regarding the fly. . . Calliphoridae or Sarcophagidae? My field guide says that Calliphoridae have only 2 or 3 bristles on top of the thorax, while Sarcophagidae have 4 bristles. I believe my fly has 4 bristles.
Posted by Tony Irwin on 25-06-2010 08:44
#6
Treat your field guide with caution! - many Calliphoridae have 4 or 5 pairs of dorsocentral bristles.
