Field Grasshopper or..

JRsbugs · #1 (**permalink**) 21-09-2009, 03:00 PM

Hi,

Taken on 6th August 2009, it was at the top of my south facing window. It should be a Common Field Grasshopper Chorthippus brunneus, but matches exactly the sample as shown on David Elements gateway of a male BOW-WINGED GRASSHOPPER Chorthippus biguttulus BROWN FORM which was taken in France. The wing near the rear is bowed, not a continuous curve.

David Element's Wildlife Web Page Orthopteroids 10 - Bow-winged Grasshoppers 1

This of course is near Lincoln UK. All markings are identical to David Element's grasshopper as far as I can see.

Janet

tristanba · #2 (**permalink**) 21-09-2009, 05:16 PM

looks like Field Grasshopper to me

Jason Green · #3 (**permalink**) 21-09-2009, 06:04 PM

Afternoon Janet,

Field Grasshopper for me too. The Bow-winged isn't a UK species.

Take care,

Jason

JRsbugs · #4 (**permalink**) 21-09-2009, 08:50 PM

Quote:

Originally Posted by tristanba

looks like Field Grasshopper to me

Thanks Tristan. It did to me too until I saw the pic on David Element's site. Why then does the wing look to have the same 'bow' as shown in the pic there? Or am I seeing it wrong? He has said at the bottom:

Quote:

This insect may only be distinguished from the morphologically very similar Field Grasshopper Chorthippus brunneus by close examination of the forewing structure and these are hopefully genuine examples of this species.

Also:

Quote:

If the climate continues to warm up in the UK this species is a likely candidate for future addition to the British fauna.

JRsbugs · #5 (**permalink**) 21-09-2009, 08:51 PM

Quote:

Originally Posted by Jason Green

Afternoon Janet,

Field Grasshopper for me too. The Bow-winged isn't a UK species.

Take care,

Jason

Yes I do know it isn't a UK species as such Jason, but things do change.

Jason Green · #6 (**permalink**) 21-09-2009, 08:55 PM

Yes - the Southern Oak Bush-cricket is one such example. With these natural introductions though, they usually appear further South first. The times I myself used to look at insects, wondering that!

EDIT:

Compare it to this...

Here with a broadside, the wing veins curve gently upwards - which gives the illusion of the wing pointing slightly upwards too.

Dogghound · #7 (**permalink**) 21-09-2009, 09:14 PM

Definately a Field grasshopper.

JRsbugs · #8 (**permalink**) 21-09-2009, 09:33 PM

Quote:

Originally Posted by Jason Green

Yes - the Southern Oak Bush-cricket is one such example. With these natural introductions though, they usually appear further South first. The times I myself used to look at insects, wondering that!

EDIT:

Compare it to this...

Here with a broadside, the wing veins curve gently upwards - which gives the illusion of the wing pointing slightly upwards too.

Thanks for the confirmation Dogg.

Jason, now you have posted that pic I will show you the part I meant. The pic you linked to does not have this bowed section. Now if you will, please check out the cropped part of the pic I was referring to on David Element's site.

Oh and yes, definitely not in Lincolnshire LOL!

Dogghound · #9 (**permalink**) 21-09-2009, 09:35 PM

That looks like the hind wing and forewing overlapping.

JRsbugs · #10 (**permalink**) 21-09-2009, 09:42 PM

Quote:

Originally Posted by Dogghound

That looks like the hind wing and forewing overlapping.

Yes I agree Dgg, but isn't that what gives the bowed shape? It is supposed to be the forewing giving this shape? I think that is what I have read somewhere anyway!

Jason Green · #11 (**permalink**) 21-09-2009, 09:54 PM

Quote:

Originally Posted by JRsbugs

Jason, now you have posted that pic I will show you the part I meant. The pic you linked to does not have this bowed section. Now if you will, please check out the cropped part of the pic I was referring to on David Element's site.

Sorry, I'm lost. As Tristan, Dan and I said - your image is of the Field Grasshopper. The one on David's site is of the Bowed. You've cropped your image to show a section of wing that you can't see on the one I had added for the sake of comparison. Are you therefor saying yours IS a Bowed, the one I linked wasn't a Field, or something else? As I said, I'm lost!

It may of course be the difference in wing venation structure of males compared to females.

Dogghound · #12 (**permalink**) 21-09-2009, 10:00 PM

Your not getting this mixed up with the costal bulge are you?

JRsbugs · #13 (**permalink**) 21-09-2009, 10:03 PM

Quote:

Originally Posted by Jason Green

Sorry, I'm lost. As Tristan, Dan and I said - your image is of the Field Grasshopper. The one on David's site is of the Bowed. You've cropped your image to show a section of wing that you can't see on the one I had added for the sake of comparison. Are you therefor saying yours IS a Bowed, the one I linked wasn't a Field, or something else? As I said, I'm lost!

It may of course be the difference in wing venation structure of males compared to females.

What I'm saying Jason is to consider the possiblity of mine being a Bow-winged.

I am not saying the one you linked to is not a Field Grashopper.

What I am saying is the flow of the wings is what separates the two as far as I know. As I quoted above from David Element's site:

Quote:

This insect may only be distinguished from the morphologically very similar Field Grasshopper Chorthippus brunneus by close examination of the forewing structure and these are hopefully genuine examples of this species.

Quote:

The eponymous 'bow-wing' refers to a small bulge on the costal margin of the forewing of the male which is just visible in this photograph.

I hope that is more clear.

No Dogg, I know where the costal bulge is, that is towards the head end of the wing.

JRsbugs · #14 (**permalink**) 21-09-2009, 10:04 PM

My pics will enlarge more if you click on them to get a better view.

Dogghound · #15 (**permalink**) 21-09-2009, 10:18 PM

Male Field grasshoppers have a less pronounced version of the bow too. Which could explain yours. If you look at some images you will see it is there but more shallow.

JRsbugs · #16 (**permalink**) 21-09-2009, 10:29 PM

Quote:

Originally Posted by Dogghound

Male Field grasshoppers have a less pronounced version of the bow too. Which could explain yours. If you look at some images you will see it is there but more shallow.

That might explain it Dogg, I found a decent pic which shows a very slight bow but not as pronounced as mine. The flow is still continuous, where on mine it shows a definite bulge.

Another difference is the wing length, with the Bowed being a little shorter than the Field. Mine does look shorter if you compare this pic as well as the one Jason linked to, although I am seeing some with very short wings so not sure where the difference comes in.

Try putting the pics side by side for a good comparison.

http://www.cgm-gardenlife.co.uk/Imag...r-img_4854.jpg

JRsbugs · #17 (**permalink**) 22-09-2009, 11:23 AM

It occurred to me when I woke this morning that this may have come from Belgium as I had friends visit about 2 weeks before seeing it. They brought a few plants so it might have been in those!

GuyF · #18 (**permalink**) 22-09-2009, 06:10 PM

Wing shape seems to vary a lot in Field Grasshoppers, here are a couple of examples from the Gallery that look similar to your individual

From what I've read, the two species are almost indistinguishable in the field because of these variations, although one way they can be separated is by the song, Bow-winged apparently make a chirping call whereas Field Grasshoppers make a rattling noise.
Guy

JRsbugs · #19 (**permalink**) 22-09-2009, 08:10 PM

Thanks Guy, yes they do have that bowed wing too! I have also read about their calls, but that is something which is rarely, if ever heard. That does leave the question open, they could be here!

JRsbugs · #20 (**permalink**) 25-09-2009, 12:50 PM

This keeps playing on my mind as I really want to know if the Field Grasshopper can have the bowed wing as well.

As GuyF stated, and I have read this too:

Quote:

From what I've read, the two species are almost indistinguishable in the field because of these variations, although one way they can be separated is by the song, Bow-winged apparently make a chirping call whereas Field Grasshoppers make a rattling noise.

But the wording in the field means just that, in the field where only visual identification is available, i.e. binoculars, eyes.

And as stated on David Element's site:

Quote:

The male Bow-winged Grasshopper has a broader costal area (see enlargement of second photograph) and slightly shorter wings than the Field Grasshopper although these characters are not easy to see without substantial magnification.

I think in my pics there is "substantial magnification", not "in the field" as such. The broader costal area, which is I imagine broadened by the 'bow' as well as the slightly shorter wings are visible in my pics.

Does anyone have a good description in a good book of the Field Grasshopper? As far as the pics in the Gallery go, I wouldn't take anything for certain as I do know many pics there are incorrect, take for example all (19 pics on last view) of Calliphora vomitoria are incorrect, there seems to be no-one who will make the corrections even when pointed out.

GuyF · #21 (**permalink**) 25-09-2009, 01:09 PM

Quote:

Originally Posted by JRsbugs

Does anyone have a good description in a good book of the Field Grasshopper? As far as the pics in the Gallery go, I wouldn't take anything for certain as I do know many pics there are incorrect, take for example all (19 pics on last view) of Calliphora vomitoria are incorrect, there seems to be no-one who will make the corrections even when pointed out.

Sorry if I've misunderstood you here, but I'm sure that the two photos that I posted are of Field Grasshoppers, id points include:
-Costal bulge on wing
-Very hairy thorax
-Keels strongly angled
These features combined rule out the other UK species. The book 'A Photographic Guide to the Grasshoppers & Crickets of Britain and Ireland' is a very useful one for identification, a few of the male Field Grasshoppers illustrated show similar wing shapes to the ones in the photos I posted. Bow-winged Grasshopper is mentioned as a potential colonist too, although it doesn't included photos or details of how to identify them.
Guy

JRsbugs · #22 (**permalink**) 25-09-2009, 01:29 PM

If you know your grashoppers that well then I have to take your word (and others) for it Guy, no offence meant but so many people make random guesses with no scientific evidence and I'm working blind here so I don't know who really does know for sure.

But your book does state as you have said:

Quote:

Bow-winged Grasshopper is mentioned as a potential colonist too, although it doesn't included photos or details of how to identify them.

Thus still giving me no real scientific evidence, lol, don't worry I'm like a dog with a bone when I get going and want all the evidence.

GuyF · #23 (**permalink**) 25-09-2009, 02:05 PM

Quote:

Originally Posted by JRsbugs

If you know your grashoppers that well then I have to take your word (and others) for it Guy, no offence meant but so many people make random guesses with no scientific evidence and I'm working blind here so I don't know who really does know for sure.

But your book does state as you have said:

Thus still giving me no real scientific evidence, lol, don't worry I'm like a dog with a bone when I get going and want all the evidence.

Don't worry, no offence taken

There are relatively few people who are interested in grasshoppers, so I'm sure it would be very easy for a species like the Bow-winged to be overlooked. From doing some more research, there are apparently differences in the number of stridulatory pegs in the two species, so that's one way you may be able to identify it, although you would probably need either a dead grasshopper or a lot of patience to be able to count them!
Guy