Diptera.info - Discussion Forum: Drosophila ID

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Drosophila ID
Widus	#1 Posted on 28-11-2020 13:07
Member Location: Posts: 70 Joined: 12.06.10	Hi, I can't put a name on these two female Drosophila specimen. They were collected August 25, 2020 from a jar in which I raised Culex pipiens f. molestus larvae that contained a few stems from flowers bought at the market. The jar was closed so the Drosophila larvae are likely coming from these stems. These two Drosophila might belong to the repleta group but none really fit perfectly in my opinion. What do you think? Christian P.S. Click on the images to enlarge them. Christian Widmann : Suisse : Lausanne : 1010 : 25/08/2020 Altitude : 632 m - Taille : Corps (2.8-3.3 mm); ailes (2.5-2.9 mm) Left, specimen 1; right, specimen 2 Réf. : 271344 Christian Widmann : Suisse : Lausanne : 1010 : 25/08/2020 Altitude : 632 m - Taille : Corps (2.8-3.3 mm); ailes (2.5-2.9 mm) Réf. : 271346 Christian Widmann : Suisse : Lausanne : 1010 : 25/08/2020 Altitude : 632 m - Taille : Corps (2.8-3.3 mm); ailes (2.5-2.9 mm) Réf. : 271347 Christian Widmann : Suisse : Lausanne : 1010 : 25/08/2020 Altitude : 632 m - Taille : Corps (2.8-3.3 mm); ailes (2.5-2.9 mm) Réf. : 271348 Christian Widmann : Suisse : Lausanne : 1010 : 25/08/2020 Altitude : 632 m - Taille : Corps (2.8-3.3 mm); ailes (2.5-2.9 mm) Réf. : 271349 Edited by Widus on 28-11-2020 13:14


Jan Maca	#2 Posted on 28-11-2020 18:01
Member Location: Posts: 1296 Joined: 25.03.10	Most probably D. repleta (darkened tip of 1st costal section, rather dark eyes, wing of normal length), rather freshly emerged and thus somewhat paler. Edited by Jan Maca on 28-11-2020 18:05


Widus	#3 Posted on 29-11-2020 09:52
Member Location: Posts: 70 Joined: 12.06.10	Thank you Jan for your message and providing an explanation for the rather light coloration that put me off the track.


Widus	#4 Posted on 17-12-2021 17:17
Member Location: Posts: 70 Joined: 12.06.10	I have barcoded one the flies (COX1 sequence). It matches (100%) Drosophila mercatorum. This species is thought to be native to South America. No wonder I had a hard time to put a name on it. D. mercatorum has a cosmopolitan distribution and it seems to have reached Switzerland (this would be the first mention to my knowledge) Edited by Widus on 17-12-2021 17:18


Carnifex	#5 Posted on 17-12-2021 22:58
Member Location: Vienna, Austria Posts: 2035 Joined: 23.06.15	Interesting find! Don't know if that feature is of good use in freshly emerged specimen as well, but the fore coxa in D. repleta is darker than the rest of the leg - here it is the same color. There is, however, one caveat: According to Bächli, D. mercatorum should not have a darkend costal spot. Apart from D. repleta, the other species recorded in Europe with that feature is D. buzzatii - and that species has light front coxae, and is described to have a small dark band at the base of the tarsus - I think I might spot a faint ring in some of the photos where the leg is visible... Edited by Carnifex on 17-12-2021 23:08 Cheers, Lorin Font Color All requests are from the urban area of Vienna, if not otherwise stated. My Diptera observations (and other living forms) can be found here, and corrections or comments over there would also be appreciated.


Jan Maca	#6 Posted on 18-12-2021 11:56
Member Location: Posts: 1296 Joined: 25.03.10	Apparently, the colour characters are sometimes confusing in the repleta group - or the analysis is not 100 % certain? Not long ago I learnt that the dark rings on tibiae (not on tarsi) may be present in D. hydei (Diptera.info 27-09-2019 18:04). In the present specimens, molecular analysis shows that the costal darkening may not be quite certain character. I determined thes specimens as "most probably repleta" also because repleta is a relatively common species, while mercatorum and buzzatii were not as yet known from well-studied Switzerland. But, with global warming and global exchange of goods, who knows? There are somewhat more than 100 known repleta-group species in the world (see taxodros. uzh.ch).