Diptera.info :: Identification queries :: Diptera (adults)
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 Dolichopodidae Campsicnemus?
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| Tony Irwin |
Posted on 19-12-2011 15:42
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 Member Location: Norwich, England Posts: 7347 Joined: 19.11.04 |
Both of the last photos show long ventral ciliation on the front metatarsus - this is not a character of mammiculatus, but is for scambus.
Tony ---------- Tony Irwin |
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| Igor Grichanov |
Posted on 19-12-2011 16:59
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 Member Location: St.Petersburg, Russia Posts: 1818 Joined: 17.08.06 |
Yes, it is better to consider it melanistic scambus, than an undescribed species.
Igor Grichanov |
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| blowave |
Posted on 19-12-2011 19:43
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 Member Location: LINCOLN, UK Posts: 3151 Joined: 27.06.07 |
Igor Grichanov wrote: Yes, it is better to consider it melanistic scambus, than an undescribed species. You seem to be a little unsure about that Igor.  I don't think it's better to go with anything where there is doubt. I must say I am still in doubt, however the trend is to go with what is already a described species, my gut feeling still tells me not to. I have to accept that not all the necessary details are showing well enough, but maybe enough to give rise to doubt. I managed to download the pdf which Paul linked to, and copied some drawings. I also found your keys, Igor, which include all the Campsicnemus species. The two species split at couplet 14, and it depends there on one critical feature. That is the conical protrusion or "ventral apophysis" near the apex of the mid femur. Although this is not very clear on my fly, it does appear to have something more substantial than hairs at that point as shown in the drawing. 14. Mid femur with ventral apophysis at apex; legs black ..................................... 15 – Mid femur without ventral apophysis at apex; legs various in colour …………. 16 http://www.biosoi.../N-198.pdf One other thing which troubles me is the wing venation as shown on a drawing of C. scambus shows converging M1 and R4+5 veins which mine does not have. blowave attached the following image:  [97.04Kb] http://cubits.org... |
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| blowave |
Posted on 19-12-2011 19:44
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Member Location: LINCOLN, UK Posts: 3151 Joined: 27.06.07 |
Wings
blowave attached the following image:  [92Kb] http://cubits.org... |
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| blowave |
Posted on 19-12-2011 19:46
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Member Location: LINCOLN, UK Posts: 3151 Joined: 27.06.07 |
C. scambus legs 1 & 2
blowave attached the following image:  [76.87Kb] http://cubits.org... |
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| blowave |
Posted on 19-12-2011 19:47
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Member Location: LINCOLN, UK Posts: 3151 Joined: 27.06.07 |
C. mammiculatus legs 1 & 2
blowave attached the following image:  [89.15Kb] http://cubits.org... |
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| blowave |
Posted on 19-12-2011 19:50
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Member Location: LINCOLN, UK Posts: 3151 Joined: 27.06.07 |
Does this show a "conical apophysis"? In my opinion it could have one, the angle is a little from below but there's definitely something there.
blowave attached the following image:  [91.96Kb] http://cubits.org... |
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| Igor Grichanov |
Posted on 20-12-2011 08:34
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Member Location: St.Petersburg, Russia Posts: 1818 Joined: 17.08.06 |
Dear Janet, your main prolem is the absence of collected material, therefore some doubt will remain forever. Regarding your photos, fore leg setation well differs from mammiculatus, being close to scambus. Mid leg is rather unclear. See mid leg of what I consider true scambus.
Igor Grichanov attached the following image:  [73.12Kb] Edited by Igor Grichanov on 20-12-2011 08:35 Igor Grichanov |
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| blowave |
Posted on 20-12-2011 13:08
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Member Location: LINCOLN, UK Posts: 3151 Joined: 27.06.07 |
Igor, that leg does look quite different to my fly, to me at least but different angles can show it differently. The fly was on glass so it may not be showing the tarsus correctly considering shadows or reflections. One photo does appear to show slightly longer setae on the fore basitarsus than on the drawing. Yes, the middle leg is dubious. When I took these I had no idea it would be so difficult to assess, if I knew my diptera better I would have kept other shots which might have shown more but it is a slow learning process, and I only take specimens if they are already dead as you know. Once I took one and got the wrong fly, I had a nightmare that night but the fly was smiling at me so it forgave me. 
http://cubits.org... |
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| blowave |
Posted on 20-12-2011 14:08
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Member Location: LINCOLN, UK Posts: 3151 Joined: 27.06.07 |
I had a bright idea to blow the photos up more than 100% then took some screen snips, it worked! It might show a little better the likelihood of shadows, and longer setae from the second front tarsus segment. Also the mid leg tarsus 2nd and 3rd segments don't look to have as long setae as scambus. blowave attached the following image:  [136.97Kb] http://cubits.org... |
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| blowave |
Posted on 20-12-2011 14:14
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Member Location: LINCOLN, UK Posts: 3151 Joined: 27.06.07 |
Front tarsus from the semi frontal view.. I can see a few longer setae which appear to be coming from the dorsal side, again there appears to be longer setae from the ventral second segment.
blowave attached the following image:  [110.2Kb] http://cubits.org... |
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| blowave |
Posted on 20-12-2011 14:15
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Member Location: LINCOLN, UK Posts: 3151 Joined: 27.06.07 |
Mid leg from above..
blowave attached the following image:  [95.5Kb] http://cubits.org... |
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| Marc Pollet |
Posted on 22-12-2011 01:21
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Member Location: Welle (Denderleeuw) Posts: 161 Joined: 02.06.05 |
Dearest, It's amazing how much is written over a simple Campscinemus scambus male as you photographed sufficiently accurate and how much excitement and confusion is created during the process (I wonder if this is the main aim or not?). Fact is that I remain convinced that it is of very little use that people just guess and leave you with this sometimes useless information. I am a strong advocate that anybody that presents an identification should exactly mention on what basis this identification is based. It makes one think (the identifier in the first place) twice and forces him to check the literature. If all of this is too much effort, I gues it would be better not to react. And if not all decisive features are clearly visible, one should stick to a clear guess. Cheers, Marc |
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| blowave |
Posted on 22-12-2011 03:35
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Member Location: LINCOLN, UK Posts: 3151 Joined: 27.06.07 |
Marc Pollet wrote: Dearest, It's amazing how much is written over a simple Campscinemus scambus male as you photographed sufficiently accurate and how much excitement and confusion is created during the process (I wonder if this is the main aim or not?). Fact is that I remain convinced that it is of very little use that people just guess and leave you with this sometimes useless information. I am a strong advocate that anybody that presents an identification should exactly mention on what basis this identification is based. It makes one think (the identifier in the first place) twice and forces him to check the literature. If all of this is too much effort, I gues it would be better not to react. And if not all decisive features are clearly visible, one should stick to a clear guess. Cheers, Marc Thank you for your opinions Marc. I know I am dealing with people here who have studied Dolichopods a great deal, including yourself so as you so rightly state it is a good idea to state on what basis an identification is based, perhaps you could also do this? I am aware however that some people's time is limited, so whatever little information can be given to me is greatfully received. The journey to the conclusion can often be advantageous to someone such as myself who has not studied diptera to the extent you have, but I'm not doing too bad due to my own efforts. I have learnt more due to this query because I needed to find out for myself the truth, in doing so I found Igor's keys to all the Campsicnemus species in the Palearctic region. Due to Paul's input, I found drawings of many Dolichopods on Faune de France which are very useful. I would imagine many people have also benefited from this discussion. I keep an open mind on this. Cheers! 
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