Thread subject: Diptera.info :: Horse-flies esp this one

Posted by richard on 31-07-2006 15:49
#1

I am a complete novice regarding Diptera and have just registered here. I enjoy a bit of photography and butterflies.

This beastie I have identified as Chrysops relictus. She (I presume) tried to bite me several times and after I had taken this on my cap, I did let it briefly bite my hand to get picture of that too!

I note a comment from a message fro 2004 that "Male: the eyes are not broadly separated on the top of the head and the snout is not adapted for piercing. The males are quite innocent and feed on nectar."

I realise it is a horse-fly and would like to know more about them please. Any idea why 'horse-fly' as thy bite cattle (?sheep ?deer) too?

Broadly how many sp. are there in the UK?

Does this relictus have an English or 'common' name?

Thanks

richard

Edited by richard on 31-07-2006 15:54

Posted by Tony Irwin on 31-07-2006 16:16
#2

Hi Richard
This is a Chrysops. The combination of the inverted "v" mark on the sceond tergite and reddish tibiae make it Chrysops relictus, so full marks! ;)
C.viduatus has a small black triangular or square spot in the yellow of the second tergite, while C. sepulcralis (no yellow on abdomen) and C.caecutiens both have blackish tibiae. Only the four species occur in Britain (that we know about so far!)
The genus is known as the "Deer Flies", and Alan Stubbs has coined English names for each of them, but I couldn't tell you what they are, nor do I think they should be used - in an international forum like this, we all use latin names, and it makes life so much easier!:D In Britain, the term "cleg" is used for small tabanids of the genus Haematopota, the deer flies are Chrysops and all the others are horse flies. They females will bite any large mammal that doesn't swat them first. Males feed on flowers as do females some of the time, but the British species all need a blood meal to mature the eggs.
As you've discovered the tabanids make excellent photographic subjects. Not only have they got the most beautiful eyes of all insects, but they can be easily encouraged to sit very still while being photographed. All you need is a friend with a high pain threshhold, and a fondness for sunbathing in tight black clothing. :D

Edited by Tony Irwin on 31-07-2006 16:24

Posted by richard on 31-07-2006 19:00
#3

I thought I had replied but taht seems to have been lost.

Thanks Tony, I am now a lot clearer about what I have read from less well informed sources.

How common are deer flies? Do the females from all 4 UK sp. have such a painful bite?

Generally speaking are they more of less common than true horse-flies?

Thanks

richard

Posted by conopid on 31-07-2006 21:56
#4

Oh boy, are C relictus common and persisitent biters in UK - yes they are! I ahve been absolutey plagued by them for the last few weeks. You catch one or swat it and another immediately appears and starts circling ready for biting. Still, they are quite beautiful flies.....

Posted by Tony Irwin on 01-08-2006 21:10
#5

Chrysops are quite common through Britain, but sepulcralis is restricted to Dorset, Hampshire, the west of Ireland and southern Scotland.
As Nigel says, they can be very persistant and tend to land quietly on the back of your neck. The only time I had a bad reaction to a tabanid bite was a Chrysops on the neck. It escaped, so I can't tell you what species it was!:) In the US, this habit of flying to the back of one's head has been used to develop a control system - see
http://www.leeval...at=2,51555
(The pictures look like they could be faked, but it might be worth trying, Nigel! ;))
Chrysops are often more common than other species, but I have been in areas where Hybomitra or Tabanus are more frequent. Usually Haematopota predominate. Often, Chrysops are associated with woodland, but last weekend on the Norfolk saltmarhes, Chrysops relictus was the biter, while Atylotus latistriatus were equally common, but feeding on flowers only - not paying any attention to my blood. B)

Edited by Tony Irwin on 01-08-2006 21:16

Posted by richard on 02-08-2006 16:11
#6

Thanks again Tony.

I am slowly getting my head around the difference species and geni (is that the plural of genus?)

Could I just clarify this please
"Chrysops are often more common than other species, but I have been in areas where Hybomitra or Tabanus are more frequent. Usually Haematopota predominate."

Do you mean Hybomitra predominate or are members of the genus Haematopota *generally speaking* (I appreciate much depends on where you are in the UK) the most common biting fly with Chrysops relictus generally speaking being a commoner biting fly than the horsefies (Atylotus, Hybomitra or Tabanus of which group Atylotus latistriatus is common but doesn't tend to bite!) ???

I hope you don't think I am being too pedantic but I have 'dusted off' a redundant butterfly/moth net and want to go find some more!

Richard

Edited by richard on 02-08-2006 16:22

Posted by Tony Irwin on 02-08-2006 17:21
#7

Hi Richard
The plural is genera. (I think my old latin teacher would have called it an irregular noun. :) )
To clarify - generally in Britain, you are most likely to get bitten by Haematopota. However in many places (particularly woodland) Chrysops is more in evidence. And there are some places (and some times) where Hybomitra is the commonest, and yet others where Tabanus is apparently most abundant. By and large, though, these larger horse flies are less frequent than the smaller species. Atylotus is seldom met with, but can be locally abundant.
If you want to find more, visit anywhere there is damp ground, especially unpolluted standing water, fresh or brackish. Hot weather helps.
Aylotus latistriatus is not common, rather it is localised (saltmarshes in Britain), and may be plentiful where it occurs. it does bite, but not at every opportunity. Evidently at some point in the females' development, sea lavender (Limonium) is more attractive than blood. Despite being a well-studied group of flies there's still plenty to learn about tabanids, particularly the habits of males. If you haven't got a copy, do obtain Stubbs and Drake - British Soldierflies and their Allies. It's packed full of information and useful tips. It's not expensive for the hours of pleasure you'll get from studying these flies. B)

Posted by richard on 02-08-2006 17:50
#8

Brilliant! I have some credit on Amazon, hope they have the book you recommend.

Thanks again.

Richard