Diptera.info :: Identification queries :: Diptera (adults)
 Volucella inflata / Volucella pellucens?
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| kellytjhe |
Posted on 06-02-2009 22:02
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Member Location: Posts: 4 Joined: 06.02.09 |
Hi I took this photo last year 28-05-2008 Can somebody tell me the differrence between Volucella inflata and Volucella pellucens? And wich species is on the picture? Regards Kelly kellytjhe attached the following image:  [27.84Kb] Edited by kellytjhe on 06-02-2009 22:11 |
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| Stephane Lebrun |
Posted on 06-02-2009 22:18
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 Member Location: Le Havre, France Posts: 8248 Joined: 03.03.07 |
Welcome at this forum. Female of Volucella inflata has a wider frons (about twice as wide as this one). So Volucella pellucens for your specimen. Stephane. |
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| kellytjhe |
Posted on 06-02-2009 22:29
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Member Location: Posts: 4 Joined: 06.02.09 |
Oke I guess you are right but why can i not find any other Volucella pellucens with a Yellow scutellum and crown shaped mark on the scutum ?
Edited by kellytjhe on 06-02-2009 22:44 |
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| Stephane Lebrun |
Posted on 06-02-2009 23:36
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Member Location: Le Havre, France Posts: 8248 Joined: 03.03.07 |
You are right, one expects to see a more black scutum and scutellum, and this is puzzling me, but I assume colour is a more variable character than frons width. Where was the photo taken ? Edited by Stephane Lebrun on 06-02-2009 23:39 Stephane. |
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| kellytjhe |
Posted on 07-02-2009 09:02
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Member Location: Posts: 4 Joined: 06.02.09 |
The picture is taken in the Netherlands. nature park "Loonse en Drunense duinen". |
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| John Smit |
Posted on 08-02-2009 10:36
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 Member Location: Utrecht Posts: 565 Joined: 05.10.04 |
I'd vote for V. inflata given the thorax colouration and the generally more yellow habitus, e.g. in the wings and probably also the second tegite. With the annotation that the Loonse en Drunense duinen are a little outside it's known range in the Netherlands, but the species seems to have become more common over the past years. I don't know V. inflata that well, so I cant judge if the width of the frons is too small. However if this is true, than the first thing that comes to mind is that it mighth be a partial gynandromorf (partly female, partly male). I have seen this with several Platycheirus and Cheilosia specimens and the frons width of these specimens is always in between normal males and females. John |
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| Stephane Lebrun |
Posted on 08-02-2009 10:55
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Member Location: Le Havre, France Posts: 8248 Joined: 03.03.07 |
Hello John, that would explain many things indeed ! I never think to this intersex phenomenon. "Normal" females of V. inflata have much broader frons, we can see this in our french site gallery : http://www.galeri...flata.html and on Cyrille Dussaix ' site : http://pagesperso...Liste.html Edited by Stephane Lebrun on 08-02-2009 10:55 Stephane. |
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| Menno Reemer |
Posted on 08-02-2009 11:00
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Member Location: Posts: 343 Joined: 10.06.04 |
I agree with Stephane that the width of the frons is a more reliable character. I have checked the specimens in my collection and in this character the specimen on the picture agrees with V. inflata. Besides, I have some V. pellucens in which the scutellum is somewhat pale, although not as pale as in this picture. The way the wings of this specimen shine suggests that it is teneral (just came out of its pupa). Teneral individuals tend to be much paler in colour than their more mature conspecifics. Another character in favour of V. pellucens is the paleness of tergite 2. As far as I know (I've checked 7 specimens of V. inflata) tergite 2 is always clearly darker in V. inflata. And a bit of circumstancial evidence already noted by John: the Loonse & Drunense Duinen would be a real outlier in the Dutch distribution of V. inflata. |
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| Zeegers |
Posted on 08-02-2009 11:29
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Member Location: Soest, NL Posts: 19009 Joined: 21.07.04 |
The legs are completely black, whereas the knees are reddish in inflata. So, given all the evidence, I still tend to pellucens, though it is very confusing indeed. I can't find any other example of pellucens with red on the thoracic dorum before the scutellum. Maybe a flash has highly stressed this feature ? Flashes can play dirty tricks. Theo Theo |
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| Gerard Pennards |
Posted on 08-02-2009 12:27
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 Member Location: Amersfoort Posts: 1914 Joined: 07.06.04 |
I agree with Menno and Theo, it's a female Volucella pellucens, probably just emerged from it's pupa. One needs to say there's a difference in coloration between male and female, Whereas the males tend to be very dark on the thorax and scutellum (http://www.glaucus.org.uk/Hoverfly030.jpg), in the female the scutellum and the sides of the thorax can be considerably lighter in color, creating the coloration you see on the picture (see also: http://www.kolumbus.fi/hannu.j.tanner/diptera/Volucella_pellucens_IMG_9518.jpg). The only somewhat strange feature is indeed the yellow patch on the thorax just before the scutellum, but that is a variation in the color I think. It will darken when the specimen matures. I found one picture in which one can see a yellow patch in front of the scutellum, but smaller. http://www.chili-balkon.de/viecher/schwebfliegen/bilder/gemeine_waldschwebfliege_4375.jpg Greetings, Gerard Edited by Gerard Pennards on 08-02-2009 12:28 Greetings, Gerard Pennards |
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| Zeegers |
Posted on 08-02-2009 12:41
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Member Location: Soest, NL Posts: 19009 Joined: 21.07.04 |
Stubbs gives an interesting feature. Scutellum black haired in pellucens, orange in inflata. Here, clearly lighthaired. If you look at the face, you may observe the face is strongly broadening towards the mouth margin. SO, I'm starting to believe it is inflata. SOrry, Gerard. (missed you yesterday, by the way) Theo |
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| Gerard Pennards |
Posted on 08-02-2009 13:13
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Member Location: Amersfoort Posts: 1914 Joined: 07.06.04 |
Yeah, maybe, if we're stuck with only this picture there are several possibilities with their pro's and contra's! :-) I still tend to think it's pellucens (hair color can be lighter in teneral specimens?), but maybe I'm wrong. Yesterday I was up and ready, but I just recovered from a 10 day flu attack, and in the morning there were no direct trains going from Amersfoort to Amsterdam, so it would be a long trip. I was not fit enough to do so, so I called John and said I wasn't coming. But Theo, we still have to make an appointment to pick up my material (assuming you're ready with it). Greetings, Gerard Edited by Gerard Pennards on 08-02-2009 13:14 Greetings, Gerard Pennards |
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| Menno Reemer |
Posted on 08-02-2009 14:10
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Member Location: Posts: 343 Joined: 10.06.04 |
How can you tell by this picture what colour the hairs on the scutellum are? I can't disinguish a single hair (except perhaps vaguely some marginal bristles), let alone I can judge their colour. I have compared wing venation of specimens of both species and found some additional characters. In V. pellucens the apical appendix of cell R1 (the small vein between the apex of cell R1 and the costal vein) is longer than in V. inflata. In V. pellucens the apex of cell R4+5 is more angular than in V. inflata. Look at specimens in your collection and you will see what I mean. Both characters are well visible in the picture and indicate that it is V. pellucens. Another thing: hair colouration in V. inflata is variable. I have 2 specimens from NL and Belgium with black hairs on tergites 3 and 4, while in 5 French specimens these tergites arae yellow-haired. This reminds of the difference between L. lucorum and L. inopinata. However, I have extensively compared the specimens, including their genitalia, and came to the conclusion that all of them belong to one species (V. inflata). This is just an example to point out that (at least, in most cases) colour characters are less reliable than morphological characters (like width of frons). So, I'm still convinced that it is a teneral specimen of V. pellucens! |
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| Zeegers |
Posted on 08-02-2009 18:14
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Member Location: Soest, NL Posts: 19009 Joined: 21.07.04 |
I don't have a collection. The second wing venation feature does not hold in internet pictures, but the first one does. If this is really reliable, I agree this must be pellucens. As I keep telling myself: first hunch is always the best ! Theo |
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| kellytjhe |
Posted on 08-02-2009 20:52
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Member Location: Posts: 4 Joined: 06.02.09 |
Thnx for all the explanations and answers. It is now clear to me that it is not strange to be so confused by this speciment. Regards Kelly PS. The photo was taken without flash Edited by kellytjhe on 08-02-2009 20:55 |
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