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Stegana sp? = Stegana coleoptrata
johnes81	#1 Posted on 30-05-2018 11:32
Member Location: Berlin, Germany Posts: 1978 Joined: 15.10.16	Berlin - May 2018 - 3.2 mm I want to know a few things about this specimen: 1. male or female? 2. can you recommend a species? 3. Dear Paul: do you have keys to this genus? I suspect that it could be a first record. I have a specimen but i do not yet know if it is male or female. If we cannot identify it by genitalia, then i can submit it for dna testing. Please advise me on the best method. here is a list of known species in Germany (i do not see a match): Stegana (Stegana) furta Stegana (Steganina) coleoptrata Stegana (Steganina) hypoleuca Stegana (Steganina) mehadiae Stegana (Steganina) similis i think that a first record exists for Stegana longifibula. Maybe it is not Stegana? I have not measured it at this time. Thank you for your time. edit: added measurement. Edited by johnes81 on 07-04-2020 10:45 John and Nini. Naturalists not experts.


Paul Beuk	#2 Posted on 30-05-2018 14:26
Super Administrator Location: Netherlands Posts: 19244 Joined: 11.05.04	It is Stegana, it appears to be male and, no, I am not going to suggest a species based on just this single image. DNA may be useful (if voucher samples are available) but it will be nice to link that to genitalia information. Check your mail. Paul - - - - Paul Beuk on https://diptera.info


johnes81	#3 Posted on 30-05-2018 14:56
Member Location: Berlin, Germany Posts: 1978 Joined: 15.10.16	Thank you very much, Paul. I truly appreciate the email and the info. I think that i learned my lesson from Chamaepsila rosae, when you tell me only dna can separate it from nigra - long after i completely dissected the specimen rendering dna impossible. I now wait to dissect in case i need a dna test. I'm still irritated about the Chamaepsila. I'd like to know what it is. I now wait to find out more info about a specimen. I never have a problem with dna from a lab in Munich but it is expensive. I can dissect the specimen but i don't know if you are interested in obtaining it or not. Never hesitate to ask me for a specimen. I really don't mind as long as i can see photos of the geniotalia and specimen under the microscope for my own documentation. Anyway, unless you wish to view the specimen, then i will make time to examine it myself. Thank You, Paul. By the way, i see some similarities with S. coleoptrata but also similis *which is not recorded for Berlin.) I have no experience with Stegana. John and Nini. Naturalists not experts.


Paul Beuk	#4 Posted on 01-06-2018 08:26
Super Administrator Location: Netherlands Posts: 19244 Joined: 11.05.04	Many Stegana are a b*ch and I am nott really fond of them. You can examine it yourself, but if you want to make DNA analysis possible at a later stage, remove a leg before you start and store it separately in ethanol (preferably 96% but at least 70%). Paul - - - - Paul Beuk on https://diptera.info


johnes81	#5 Posted on 01-06-2018 09:10
Member Location: Berlin, Germany Posts: 1978 Joined: 15.10.16	I have trouble with alot of Drosophilidae. Very difficult to work with at such small sizes. Much easier to dissect a 1.5mm female spider than to play around with a Drosophilidae in my opinion. I will try to examine it when i feel up to the challenge. I'm just saying, if you ever wish to view a specimen of mine, then just ask. No problem. I do not examine them immediately anymore. I wait to see if dna is necessary. I know your address from donation, so just ask John and Nini. Naturalists not experts.


johnes81	#6 Posted on 14-06-2018 20:31
Member Location: Berlin, Germany Posts: 1978 Joined: 15.10.16	I finally got around to examining this specimen and it turns out to be Stegana coleoptrata male. I am a bit shocked at the great amount of details required to match a Stegana specimen to a species. long day at the microscope. Thank you very much for helping, Paul John and Nini. Naturalists not experts.


Paul Beuk	#7 Posted on 15-06-2018 07:19
Super Administrator Location: Netherlands Posts: 19244 Joined: 11.05.04	Now you know why I wrote: Many Stegana are a b*ch and I am not really fond of them. Paul - - - - Paul Beuk on https://diptera.info


johnes81	#8 Posted on 15-06-2018 10:01
Member Location: Berlin, Germany Posts: 1978 Joined: 15.10.16	I had a little trouble with certain aspects of the specimen. The haltere are brownish but they appear to be yellow in strong lighting. I've had this problem with Pollenia before, so i have to rotate the specimen and the lighting to be certain of the color. However, the knob always seems to be darkened. The drawings are obviously based upon high magnification which my microscope cannot achieve. Thus, it is very difficult to match the aedeagus to the drawings. The keys are very helpful in this case. We can easily arrive at S. coleoptrata by keys alone. I didn't know that Stegana has those warts on the wing. Very interesting. This specimen is my first Stegana. I like the way the wings bend around the abdomen. Very cool looking. I like Stegana but i do not appreciate haviong to dissect them johnes81 attached the following image: [45.23Kb] John and Nini. Naturalists not experts.


johnes81	#9 Posted on 15-06-2018 10:02
Member Location: Berlin, Germany Posts: 1978 Joined: 15.10.16	warts on the wing are very interesting johnes81 attached the following image: [76.03Kb] John and Nini. Naturalists not experts.


johnes81	#10 Posted on 15-06-2018 10:04
Member Location: Berlin, Germany Posts: 1978 Joined: 15.10.16	i tried to remove the cerci from the membrane that attaches them to the aedeagus complex. I was able to do so but it was a very frustrating process. The transparent membrane makes them seem like they are floating in the air. The drawings are a bit off in my opinion. johnes81 attached the following image: [65.93Kb] John and Nini. Naturalists not experts.


johnes81	#11 Posted on 15-06-2018 10:05
Member Location: Berlin, Germany Posts: 1978 Joined: 15.10.16	the surstyli are easier to match with the drawings. johnes81 attached the following image: [39.56Kb] John and Nini. Naturalists not experts.


johnes81	#12 Posted on 15-06-2018 10:06
Member Location: Berlin, Germany Posts: 1978 Joined: 15.10.16	the aedeagus is very difficult to match because of the high magnification required to view all of those details. I must admit that i think that this aedeagus looks more like drawings of S. similis in certain ways. I do not have such a powerful microscope to see all of those details but this is enough for a match. johnes81 attached the following image: [46.41Kb] John and Nini. Naturalists not experts.


johnes81	#13 Posted on 15-06-2018 10:07
Member Location: Berlin, Germany Posts: 1978 Joined: 15.10.16	i cannot see the details in the drawings, however, this is easy to notice S. coleoptrata. johnes81 attached the following image: [49.38Kb] John and Nini. Naturalists not experts.


johnes81	#14 Posted on 15-06-2018 10:09
Member Location: Berlin, Germany Posts: 1978 Joined: 15.10.16	Finally, i will add a photo to the gallery. We are missing this one. Thank you very much, Paul. You make my life easier. I appreciate you very much. edit: i've submitted a photo to the gallery. Edited by johnes81 on 15-06-2018 10:14 John and Nini. Naturalists not experts.

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