Posted by magnusp on 02-12-2012 11:37
#1
This yellow Dolichopodidae looks very much lika a Neurigona, but in order to reach to this genus in the key I have to choose the option "Eyes distinctly separated below antennae, or slightly convergent towards palpi". So first question, is there an individual variation in this feature, or is maybe the touching eyes just a dehydration artifact? If it indeed is Neurigona, then I arrive at erichsoni, which is a very rare species, so I would really like to have a confirmation.
Edited by magnusp on 02-12-2012 14:49
Posted by Igor Grichanov on 02-12-2012 12:02
#4
It is
erichsoni:
—Apical segments of fore tarsus simple; sometimes 4–5th
segments slightly enlarged, flattened or curved .......... 5
5. Mesonotum yellow, usually slightly shining, without pollen
.................................................................................... 6
— Mesonotum mainly matt-dark, covered with yellowishgrey
or brownish-grey pollen ....................................... 10
6. Abdominal 5th tergite short, with distinct lateral lobe
directed downward ......................................................... 7
—Abdominal 5th tergite without lobelike lateral widenings ... 9
9. Abdomen with dark longitudinal stripe; hypopygium yellow
at base ............................................................ lineata
—Abdominal tergites with dark transverse bands along anterior
margin; fore tarsus short, 1/4 shorter than fore tibia;
hypopygium sessile, shining black; 4.0–4.5 mm ...........
........................................................................... erichsoni
See
Grichanov I.Ya. 2010. West-Palearctic species of the genus Neurigona Rondani (Diptera: Dolichopodidae). Russian Entomol. J. 19(3): 249–256.
Posted by magnusp on 02-12-2012 14:48
#6
Thank you for your reply! According to the Swedish red list, the last time erichsoni was found in Sweden was 1955, when Hugo Andersson collected one specimen close to where I found mine.
The photos were taken with a Schneider Kreuznach Componon 35 mm f4 lens used reversed on bellows. All photos are focus stacked.
I am not using any special drying technique, I just pin the flies and put them in a cardboard box for drying.