Thread subject: Diptera.info :: Hebecnema vespertina?

Posted by Rui Andrade on 03-08-2019 14:34
#1

Hi,

I think eyes have short hairs, which would indicate Hebecnema vespertina. Is it possible to confirm the ID?

location: Porto (Portugal)
date: 20/07/2019

Posted by Rui Andrade on 03-08-2019 14:34
#2

.

Posted by Rui Andrade on 03-08-2019 14:34
#3

.

Posted by Rui Andrade on 03-08-2019 14:35
#4

.

Posted by johnes81 on 03-08-2019 14:46
#5

looks ok to me. eyes sparsely haired, two av on t3, yellow knob of haltere. just be sure that there is no prealar. I think H. vespertina is a good match. If there is a problem with this id, then Nikita will weigh-in on the matter.

Edited by johnes81 on 03-08-2019 14:47

Posted by Rui Andrade on 03-08-2019 15:54
#6

Thank you. :) The next picture is not very good, but I don't see the prealar.

Posted by johnes81 on 03-08-2019 16:44
#7

looks okay to me, Rui. :)

Posted by Rui Andrade on 03-08-2019 22:46
#8

Great, thanks! :)

Posted by Nikita Vikhrev on 04-08-2019 10:33
#9

I agree with John and Nini on Hebecnema. But why vespertina? H. umbratica, I'd say.

Posted by johnes81 on 04-08-2019 10:53
#10

Then it must be H. umbratica. Thank you Nikita.
For me, i thought the eyes are toucjhing and more hairy for H. umbratica. I can't see two pd on the mid tibia so i assumed they are not present. My apologies.

Posted by Nikita Vikhrev on 04-08-2019 11:17
#11

John and Nini.
1. Eyes are hairy (rather short and sparsely, but doubtless), while in vespertina they are really bare.
2. In Moscow region, vespertina appears in late May and normally disappear till July.
Porto is 41N (Moscow 56N) and on seashore, at 20 July. I do not think that vespertina present in Portugal at all. In contrast umbratica goes very far south (till Vietnam, for example, or till Morocco), so their presence in Portugal is quite natural.

Posted by johnes81 on 04-08-2019 11:31
#12

Hello Nikita and i hope that you are having a good day :)

i remember now that i have notes about Hebecnema that i gathered from your posts. I aslo admit that have said this to me before about the time of year. I need to read your notes more often. My apologies. I get lazy sometimes.

Before i forget, i will send a pm to you now. I want to ask you about a book.

Thank you for correcting me,
John

Posted by Rui Andrade on 05-08-2019 09:52
#13

Hi Nikita, the hairs on the eyes of this specimen are really small and very difficult to see. I considered that they do not fit H. umbratica because in April I caught another Hebecnema that I identified as H. fumosa which has very long hairs on the eyes (see next picture). Later I'll post more pictures of this specimen from April in a separate post. Which characters do you need to see from this specimen to be sure of the species?

Posted by Nikita Vikhrev on 05-08-2019 12:53
#14

Hi Rui.
You are right: fumosa has eyes morehairy than umbratica. Also fumosa's eyes are more reddish while umbratica's - bronish. H. fumosa is bigger. Both these species are very predictable for Portugal, so I suppose your identifications are correct.

Posted by Rui Andrade on 06-08-2019 18:09
#15

Thank you Nikita. Regarding H. umbratica, one thing that led me astray was that in the key it says that this species has silvery parafacialia and I thought that in my specimen it was not like that.

Posted by Rui Andrade on 06-08-2019 18:36
#16

I decided to pull the genitalia a bit. Comparing to the pictures in the following links, I think it is most similar to H. vespertina. Nikita, what do you think?
http://www.spessa...hpgs2.html

http://www.spessa.../hpgs.html

Posted by Rui Andrade on 20-08-2019 23:58
#17

Does this picture of the genitalia help?

Posted by Nikita Vikhrev on 21-08-2019 08:18
#18

I never examined genitalia of Hebecnema, drawings in books look similar.

Posted by Rui Andrade on 21-08-2019 08:54
#19

Thank you Nikita. :)