Thread subject: Diptera.info :: Sapromyza ?

Posted by Arthropa on 24-07-2004 23:06
#1

Hello,

Here a little orange diptera, with 4 black spots on the abdomen.
(Saint Apollinaire (21), France - 4 mm long, wings included - 22th june 2004)

arthropa.free.fr/photos/ATH04-06-22-032.jpg
arthropa.free.fr/photos/ATH04-06-22-034.jpg
arthropa.free.fr/photos/ATH04-06-22-042.jpg

I've been proposed Sapromyza opaca as an ID.
I read too that there is some Sapromyza quadripunctata species, which could be probable ?

Thanks for your help

Posted by Arthropa on 25-07-2004 19:24
#2

Sorry, made a mistake : length is 4 mm for the body, but 6 mm wings included.

Posted by Paul Beuk on 26-07-2004 10:23
#3

Hello Benoit,

If this were Sapromyza quadripunctata, the it should have strong ocellar setae that are placed just beside the ocellar triangle. From the blow-up I made of the pictures it does not seem to be the case in this specimen. This specimen is a male (from the appearance of the tip of the abdomen) and in S. quadripunctata both the hind femur and hind tibia have strong additional setae. These are absent in this specimen as well. So, no S. quadripunctata here.

Following the keys, this specimen either belongs to S. opaca or S. zetterstedti. Unfortunately, the character that used to be given to separate these two, the number of black spots on the abdomen is not constant. Four spots used to be S. zetterstedti and six spots S. opaca and S. sexpunctata. The last one has a shining mesonotum and can be ruled out. The other two can only be separated with certainty on the basis of the genitalia. So, if someone says that it is S. opaca, I cannot say it is incorrect.

Paul

Posted by Arthropa on 27-07-2004 18:34
#4

So let's say it's (probably ! ;)) S. opaca !

On the original (big size) photos, one effectively can't see any strong setae beside the ocellar triangle.

Thanks for your help, and see you soon for some other unidentified flying insects ! ;)

Posted by Vadet on 08-08-2004 09:27
#5

On Heracleum spondylium ( scale given by the flower)

Boulonnais, on the top o?f the cliff

Dimage A1 + 2X lenses

sexpunctata ??

Best regards

Alain Vadet

www.diptera.info/forim/5-0032-4.jpg

Posted by Paul Beuk on 08-08-2004 15:18
#6

Hello Alain,

It appears as if the ocellar setae are placed beside the ocellar triangle and that there are only two rows of acrostichal setae. In that case it would be Sapromyza quadripunctata but I will check whether that species can have three pairs of spots on the abdomen. I will let you know.

Posted by Vadet on 09-08-2004 17:42
#7

Thank you for the comments, sure it would be easier if the photo was be better,

I try but it is difficult, these little flies are always moving

Best regards

Alain Vadet