Thread subject: Diptera.info :: Two diptera from near Rome in Italy

Posted by lynkos on 12-08-2005 08:50
#1

Still in my northern exile in Cornwall without much time to go "hunting", I'm passing the time by sorting through my archive shots from last year and trying to put a name to those which have escaped me to date. Here are a couple which I am still not sure about. Can anyone help?

www.naturamediterraneo.com/Public/data1/lynkos/2005811143856_CFNA04-N08-F.jpg

www.naturamediterraneo.com/Public/data1/lynkos/2005811143930_CFBA04-N18-F.jpg

Thanks in advance, :) Sarah

Posted by Kahis on 12-08-2005 09:04
#2

Phthiria (Bombyliidae)

Geomyza (Opomyzidae)

Posted by lynkos on 12-08-2005 10:19
#3

Thanks :), or should I say, grazie! Sarah

Posted by Jan Willem on 12-08-2005 17:44
#4

The second picture is indeed a species of the genus Geomyza; a female. It looks like Geomyza nartshukae Carles-Tolr?, 1993, but especially in the south of Europe specimens of Geomyza tripunctata Fall?n, 1823 may also have a rather reddish thorax. To be really sure about the identity you need to study the shape of sternite 8, which is only possible if you have collected the specimen. I suppose you have not collected it!? Still my best guess would be G. nartshukae. I have seen specimens collected by Rondani from Italy, so there is no doubt that this species occurs in Italy.

Jan Willem

Posted by lynkos on 13-08-2005 09:00
#5

Jan Willem wrote:
Still my best guess would be G. nartshukae. I have seen specimens collected by Rondani from Italy, so there is no doubt that this species occurs in Italy.Jan Willem

I have checked with the checklist of Italian fauna and they don't actually list Geomyza nartshukae, which probably means it is particularly rare here. Geomyza tripunctata however is specifically listed in the central region of Italy where I live, so statistically I suppose it is more likely to be the latter, Sarah

Posted by Jan Willem on 13-08-2005 16:59
#6

Hi Sarah,

There is an update on the Italian checklist concerning Opomyzidae (Zuijlen, J.W.A. van, 1999. Additions to recently published checklists of Opomyzidae (Diptera).-- Studia dipterologica 6(1): 205-206.). In this paper Geomyza nartshukae was recorded from Italy by me (and also from Germany and England). So this species is officially recorded from Italy. It has only relatively recently been described (1993) from Spain. I also recorded this species in other papers from Belgium, The Netherlands, Bulgaria, and Andorra. I do agree that G. tripunctata is much more common than G. nartshukae, but the latter is certainly not rare in southern Europe. I have checked my notes and it turned out that untill now I have only seen three Italian specimens of G. nartshukae. I must add though that I have seen rather few specimens of the Opomyzidae from Italy. Additional material is always welcome!
In most collections it is certainly worthwhile to check if the material identified as G. tripunctata actually belongs to this species or to G. nartshukae.

Jan Willem

Posted by lynkos on 14-08-2005 09:36
#7

Thanks Jan for this very authoritative answer. I am quite sure you're right, there is a lot of disinformation around and this is why I am so pleased to have found this site where I can be sure of a competent and reliable answer! Sarah

Posted by Jan Willem on 14-08-2005 12:04
#8

Hi Sarah,

I didn't mean to sound authoritative because I certainly don't know everything about Opomyzidae. Escpecially on the biology my knowledge is very limited. However, since Opomyzidae is my passion in diptera I sometimes overdo it.
If you have any data on the behaviour of species of the family Opomyzidae, those data are very welcome. The same counts for pictures of members of this family.

Jan Willem

Posted by lynkos on 14-08-2005 12:38
#9

I just wish I knew a small fraction of what you do! I will be more than happy to look out for other pictures of this family. It would be interesting and useful if you could give a brief and relatively layman's guide as to how best to distinguish this family from other similar, Sarah