Thread subject: Diptera.info :: Sarcophaga africa ?

Posted by zcuc on 06-12-2007 10:15
#1

10mm, Israel.

It has plumose hind tibia and red marking on tip of abdomen

Edited by zcuc on 07-12-2007 13:06

Posted by zcuc on 06-12-2007 10:16
#2

and lateral view

Posted by Tony Irwin on 06-12-2007 20:27
#3

I'd say this was Sarcophaga africa but you may have other, related species in Israel - best to check against genitalia figures

Posted by zcuc on 07-12-2007 13:13
#4

Thanks Tony,

I'm just an amateur and had never tried to extract fly genitalia. Maybe I can try and post the image of the genitalia here?
Do you know of any good referace of how to do it?

Posted by Andy Chick on 07-12-2007 13:33
#5

pape 1987 gives the procedure.

Posted by zcuc on 07-12-2007 14:54
#6

Thanks for the advice Andy but I don't have this book, do you know of any internet article?

Posted by conopid on 07-12-2007 16:53
#7

Hi
There is some good advice here: http://www.zmuc.dk/entoweb/sarcoweb/sarcweb/collect/Collect.htm

Posted by crex on 07-12-2007 16:55
#8

conopid wrote:
Hi
There is some good advice here: http://www.zmuc.d...ollect.htm

Clickable ;)

Posted by Tony Irwin on 07-12-2007 20:58
#9

I use the technique that Thomas Pape describes, but I side-pin my Sarcophaga with big minuten (if you know what I mean:)). The technque involves placing one minuten against the top of the abdomen, just in front of the genital segments. A second pin is then used to pull out the claspers. This usually results in the aedeagus being exposed as well, but occasionally it gets "jammed", and needs to be released gently with another pin. Often it is easier to exsert the claspers with a mounted minuten or fine needle, rather than holding one in forceps. The minuten are not pushed through the genitalia - just beside them to hold them in place until the fly is dry. Take great care when extracting the pins - it's really sad if the penis breaks off! :o
If you have collected a specimen without exserting the genitalia, it is sometimes possible to relax them with Barber's Fluid, so they can be prised open later, but it is much easier to exsert genitalia before the fly has dried.

Posted by zcuc on 07-12-2007 23:32
#10

Well this is my first try :)
I managed to pull the genitalia from the abdomen(1) but it seem to be coverd by thin dark membrane(2) how can I remove this part? should I just torn it?

Posted by Zeegers on 08-12-2007 10:17
#11

You are looking too high.
The orange bulb should be retracted at the ventral side from the abdomen.


Theo

Posted by zcuc on 08-12-2007 12:14
#12

Here a ventral view before I starter to poke with my needle.

Posted by zcuc on 08-12-2007 12:28
#13

Now for the second try:
I inserted the pin at the ventral side of the abdomen and tried to push it.
It was torn with the black membrane(2), that seem to be attached fairly good to the genitalia.

Now I have two question:
1. Does anyone has genetalia reference book of Sarcophaga africa which could be compared to my images?
2. What went wrong? does anyone have a photo of well extracted genetalia of Sarcophaga so I could compare?

Thanks

Posted by Kahis on 08-12-2007 12:41
#14

OK, now put the separated part in warm water with a drop of detergent for 15 minutes (or more) to soften it up a bit. Then you can remove the black tergites to expose the hidden cerci, surstyli etc. which are on the ventral side, in rest position hidden below the V-shaped 5th sternite.

Posted by Tony Irwin on 08-12-2007 14:00
#15

You should find bits looking something like this. :)

Posted by zcuc on 08-12-2007 16:03
#16

I soak it inside warm water and removed the black tergites, but couldn't find any cerci?
kahis you said it should be on the ventral side, but according to the link in this post I'd exctracted the genitalia with one needle on ventral side and one on dorsal side. so maybe the cerci were ruin?

Was it suppose to be in the green circle?

Posted by Kahis on 08-12-2007 17:09
#17

www.elisanet.fi/jere.kahanpaa/dscf4244a.jpg

Definitely the correct genus at least. Looks very similar...

Edited by Kahis on 08-12-2007 17:17

Posted by Susan R Walter on 08-12-2007 18:24
#18

Very nice thread. Informative and productive. Many thanks to Zcuc, Tony and Kahis for going through this online.

Posted by zcuc on 08-12-2007 19:44
#19

Wow, It was under my noise and I couldn't see it :) Thought those black spike are left over of the black tergites.

Too bad my poor Lupa is too weak so I'm unable to get a real closeup to verify against the drawing. Tony is it possible to get id from this bad genitalia image or does this genus has many similar genitalia?

Many thanks to all of you for helping, Hope I'll improved next time.


Posted by Tony Irwin on 08-12-2007 20:46
#20

As Kahis says, it's certainly Sarcophaga subgenus Bercaea. My feeling is that the genitalia are close enough to be S. africa. There are minor differences to the africa I've seen, but that's not surprising. Although they are the best way to tell species apart, it's worth remembering that the genitalia can vary a bit. The skill is to know how much variation is "permissible"! I don't know of any other Bercaea in Israel - so I think it is safe to call this Sarcophaga (Bercaea) africa.

Posted by zcuc on 08-12-2007 21:12
#21

Great news,
Send to the gallery.

Thanks again Tony.

Posted by Liekele Sijstermans on 12-12-2007 10:36
#22

Nice thread. Impressive to see how succesfull you where in extracting genitalia your first time.

According to Lehrer (Sarcophaginae and Paramacronychiinae du Proche Orient, 2006) Sarcophaga (B.) africa is the only species of (sub)genus Bercaea in Israel. Lehrer lives in Israel, so I expect him to know the fauna quiet well.

Other Bercaea species are from Africa. Of these species, only genitalia of S. (B.) burungae look a bit similar to your picture. According to Lehrer (Sarcophaginae de l'Afrique, 2003) "tergite genital est brun rougatre" but yours is "brun noiratre" (compare your image with arrow 2) as it is in S. (B.) africa.


Liekele

Posted by Tony Irwin on 12-12-2007 23:43
#23

Liekele -
If I translate correctly, Lehrer says that a Bercaea with a black pregenital tergite is africa, but a red pregenital tergite is burungae. Does that mean that the flies in the picture at http://www.dipter...to_id=1735 are misidentified?

Edited by Tony Irwin on 12-12-2007 23:44

Posted by Liekele Sijstermans on 13-12-2007 12:34
#24

Tony,

I do not know whether picture in the gallery is S. (B.) africa or not. We need genitalia to give positive identification.

The genitalia in this case are really equal to S.(B.) africa as far as can be told by this quality of the picture.
We may exclude burungae because of a combination of arguments
(distribution, color of pregenital tergite and more or less the shape of genitalia).

Liekele

Posted by Kahis on 15-12-2007 19:55
#25

Liekele Sijstermans wrote:
I do not know whether picture in the gallery is S. (B.) africa or not. We need genitalia to give positive identification.

The genitalia in this case are really equal to S.(B.) africa as far as can be told by this quality of the picture.
We may exclude burungae because of a combination of arguments
(distribution, color of pregenital tergite and more or less the shape of genitalia).


This thread keep on giving. Now it demonstrates one of the probems of examining male genitalia: you keep finding unexpected, interesting, possibly undescribed stuff :)