Identifying sex (Panorpidae)

[Anzu]

I took this shot a little while ago and was wondering this little guy is male or female?

And I know you have to examine the genitalia to distinguish what species it is with certainty, but does anyone have any clue to which species it is?

Thank you for any help!

[Jason Green]

Morning Anzu,

It's female - the tip of the abdomen is pointed, and called an ovipositor which is used to lay eggs. The male's genitalia is shaped like an apically-spiked club, and often held up and back over the top of the abdomen as if to replicate a scorpion's sting - hence the group's common name.

Unfortunately it isn't possible to identify these to sepecies-level from photographs, according to the latest research. It is now possible we have another species, Panorpa vulgaris, which keys out closely to P. communis.

These need to be collected and examined under the microscope. Features such as the ventral parameres would need examining. Those with P. communis specimens would be advised to double-check.

Take care,

Jason

[Anzu]

Morning Jason,

Thank you for the detailed reply, I didn't realise males kept their tail in that scorpion shape all the time! I thought maybe they popped it up like that in self defence or something lol.

I hope at some point in the future I can have a look at a male

[Jason Green]

I have very little experience with Panorpids - I think I've seen one twice, but didn't set eyes on it long enough to sex it. They're bigger than you'd think! The tail-end is probably slightly flexible, and I should have added not always raised.

[Geoff F]

The Aidgap booklet A key to the adults of British Lacewings and their allies also has a section on Scorpion Flies.

Males can sometimes be identified by a perfect photo of their genitalia but females need dissection, as Jason pointed out.