Posted by crex on 15-08-2006 22:50
#1
From midwest Sweden 2006-07-05. Found dead. Possible to ID? Might it be a female
Helophilus pendulus? TIA!
Edited by crex on 16-08-2006 07:36
Posted by jorgemotalmeida on 15-08-2006 23:56
#4
tHese 3 spots between the eyes are the calli? What are the function of calli? Is this present in Therevidae, Syrphidae, and which more flies? In all females? And in wasps I saw these spots too...
Edited by jorgemotalmeida on 16-08-2006 00:01
Posted by Tony Irwin on 15-08-2006 23:56
#5
Yes, I'd say
H. pendulus.
The three spots between the compound eyes are the
ocelli (or simple eyes). Almost all flies have ocelli, usually arranged in a triangle, and sitting on a more or less clearly defined plate called the
ocellar triangle. Sometimes the ocelli sit on a raised bump called the
ocellar tubercle, and often they have a pair of bristles, arising between the ocelli and usually pointing forwards. I tell you all this becasue the position of the ocelli and the length of the ocellar bristles are often used as identification characters.
Sometimes the
frons (the area in front of the ocelli, and above the antennae) has one or more bare shining patches. These patches are called
calli (one is called a callus), and they are found in flies like Tabanidae and Therevidae, and can be very useful identification characters.
Edited by Tony Irwin on 16-08-2006 00:07