Thread subject: Diptera.info :: Lauxaniidae

Posted by Jan Zwaaneveld on 04-07-2007 13:37
#1

I found this beautiful, appr. 5 mm long fly at Leerdam, Netherlands yesterday. I think it is Lauxaniidae. It resembles Sapromyza albiceps in the gallery, but it does not have the white head. Could anyone help me with the id of this fly?

Thank you in advance!

Posted by Jan Zwaaneveld on 04-07-2007 13:38
#2

pic 2

Posted by Jan Zwaaneveld on 04-07-2007 13:38
#3

pic 3

Posted by Jan Zwaaneveld on 06-07-2007 11:39
#4

No-one for this pretty fly? :(

Posted by Paul Beuk on 06-07-2007 11:49
#5

It is Sapromyza, not certain that it is albiceps.

Posted by Nikita Vikhrev on 06-07-2007 11:52
#6

Well, Jan, if you insist... (Lauxaniidae isn't "my" family:@)
Yes, Sapromysa.
No, not S.albiceps
I'd say Sapromyza opaca
Nikita

Posted by Jan Zwaaneveld on 06-07-2007 13:17
#7

Thanks very much for your help, Paul and Nikita! :)
I just checked: S. opaca is not on the Dutch list. Does it perhaps have a twin species or a lookalike, or ... (I do not dare to think any further)?

Posted by Jan Willem on 09-07-2007 06:35
#8

Hi Jan,

You are right, Sapromyza opaca is not on the Dutch list. I asked Bernhard Merz to have a look at your photos and he wrote the following:

Indeed, a nice Lauxaniidae, but a female making identification very difficult. Two genera are possible which have superficially the same characters, in particular the 2-3 pairs of black spots on the last abdominal tergites: Sapromyzsosoma (quadripunctata, quadricincta) and Sapromyza (opaca, sexpunctata and zetterstedti). Based on the photo I can only recognize 2 rows of acrostichal setulae, yellow antennae and palpus. Only one species fulfils these requirements: Sapromyzosoma quadripunctata. Moreover, the thorax is mat (not shining, excluding sexpunctata). I have never seen zetterstedti with more than 2 pairs of abdominal spots, excluding this species; quadricincta and opaca have 4 rows of acrostichal setulae.
That is all what I can say. In Lauxaniidae it is often impossible to make a safe identification if you do not see the specimen under the microscope, and often the genitalia need to be checked. The next time you have to catch the specimen!


So no certainty, but your specimen is probably conspecific with Sapromyza quadripunctata.

Jan Willem

Posted by Jan Zwaaneveld on 09-07-2007 14:36
#9

Well Jan Willem, I am very pleased to read all this, although there is no certainty. Thanks to you and Bernhard Merz for your help!