Thread subject: Diptera.info :: Drosophilidae - Netherlands
Posted by Paul Beuk on 07-10-2020 09:21
#1
Rather unusual species compared with what I generally see. Thorax with 8 rows of ac rather checkered brownish yellow and darker brown, mesonotum with five darker brown lines on yellowish brown background: a narrow median line between the tto median rows of ac (fading anteriorly), lines between the first paramedian lines of ac and just medial of the dc and lines just lateral of the dc, median area on sutellum darker. Abdomen very dark brown with very small paler spots medially on tergites 3-6 at anterior and posterior margins; tergites 3-6 with pale spots at anterolateral corners. Legs yellowish, preapical setae present on all tibiae. Antennae with four dorsal and two ventral rays in addition to end fork, first flagellomer rather short and dark. Palpi with one very long apical seta (almost as long as palpus) and one of about half its length just before middle. Oviscpa pale, narrow with one long seta.
Dorsal view:
Posted by Paul Beuk on 07-10-2020 09:21
#2
Lateral view
Posted by Paul Beuk on 07-10-2020 09:22
#3
Oviscapt (poor image):
Posted by Jan Maca on 07-10-2020 14:04
#4
Allowing that the specimen may be teneral, may have some setae broken, and that setae of oviscapt are poorly visible in the picture, I would say that it can be D. silvestris Basden (subsilvestris Hardy and Kaneshiro).
Prominent apical seta of palpus shows it is a species of obscura group. Pale lateral spots on abdominal tergites are in D. obscura and D. silvestris; elongate marginal setae of oviscapt show D. silvestris.
While I am reasonably sure as concerns the species group. I do not exclude that it might be some introduced species similar to D. silvestris - determination of a male would be more sure.
Btw. I use the binomen D. silvestris as D. silvestris Basden and D. silvestris Perkins now belong to different genera (D. and Idiomyia) so that no substitution of the firstmentioned name is necessary.
Posted by Paul Beuk on 07-10-2020 14:46
#5
That species was on my mind at first, too, but since the specimen is otherwise pristine I cannot believe that the only two setae broke off would be the apicodorsal setae on both sides of the oviscapt.
Unfortunately, there was only this female in the sample so I will leave it at
Drosophila (Sophophora) sp. right now. Perhaps a male will turn up in another sample...