Diptera.info :: Identification queries :: Diptera (adults)
Who is here? 1 guest(s)
 Elachiptera
|
|
| John Bratton |
Posted on 30-01-2015 16:53
|
|
Member Location: Menai Bridge, North Wales, UK Posts: 638 Joined: 17.10.06 |
Collected from a Carex bed beside a small pond, 16 January 2015, Bangor, Wales, SH54616994.
John Bratton attached the following image:  [54.42Kb] |
|
|
|
| John Bratton |
Posted on 30-01-2015 16:53
|
|
Member Location: Menai Bridge, North Wales, UK Posts: 638 Joined: 17.10.06 |
This keys to Elachiptera cornuta. However, my 1999 key says there is a second undescribed species near cornuta. In the original cornuta (Fallen) the male femoral combs have 40-50 setae in an irregular patch and the undescribed species has under 20 setae in two discrete rows. Other than being on the middle femora, I don't know where a femoral comb is. Is this it, towards the base of the dorsal surface? In which case, this specimen appears to have under 20 setae in two rows. Has this species been named yet please? John John Bratton attached the following image:  [71.22Kb] |
|
|
|
| jeremyr |
Posted on 30-01-2015 17:28
|
 Member Location: Tottenham Posts: 577 Joined: 18.05.12 |
the femoral comb is 'an area of specialised setae on the upper surface of the middle femur' and should be 'raised slightly above the surface of the femur'. So it seems like you're in the right place. As you mention it's an irregular patch rather than something more uniform, though this is when there's a large number of setae, with fewer it's more like rows. Elachiptera nr. cornuta is narrower and longer than E. cornuta - I think that's still its name Edit: it's worth noting that often ' the setae on the femoral comb merge imperceptibly into the longer, normal setae'... so 'only setae less than three times as long as the greatest diameter of their bases' are counted. Dissection and alchohol appear to be the way to count them so it's not something I've tried myself Jeremy Edited by jeremyr on 30-01-2015 19:47 |
|
|
|
| John Bratton |
Posted on 04-02-2015 12:57
|
|
Member Location: Menai Bridge, North Wales, UK Posts: 638 Joined: 17.10.06 |
Thanks for that. It seems strange that this segregate has been known about for at least 16 years but no one has formally described it. John |
|
|
|
| Jump to Forum: |
but don't see the image in the post.
