large brown harvestman for ID

[Gateside]

I have uploaded 2 pics of a large brown harvestman.
One in a low-res general view, the other is a close-up of the body.

Descriptions with photos.
Is species identification possible?

Thanks
Nigel

[Geoff F]

A few more details may help, also any other really close shots from different angles.

Firstly, what about sizes? Is the body length 5 mm or less; or 6 to 10 mm? Just how long are the legs particularly the second leg? If they are nearly 50 mm, which works out around 10 times the body length my first thought would be female Leiobunum species.

The dark 'saddle' on the abdomen stops abruptly at tergite 4 which would match.

However, to consider other species, if the legs are shorter, I would really need a view of it's 'nose' to see if there are any small bony trident shaped spines. Also a good clear side view of the ocularium (eye turret) showing the number and size of any tubercles would help.

And are there any dark brownish lines on the undersides. I can't obviously see any but I would like to be sure.

[Gateside]

Geoff, i have uploaded a partial view of the underside, and increased the contrast, so that the faint brown bars on the underside show up. They are not dark though.
(see link at bottom of page)

As to the other questions, it's difficult to assess, but have placed a ruler where the harvestman was, and assessed the size according to the pile on the carpet!
I reckon it's about 5 mm body length, and don't think the legs are that long. I reckon that the 2nd leg is about 25-30 mm only, just maybe as much as 40 mm, but I doubt it. (I had cropped the end of the leg in my saved pic, so can't get it back!)

I can't tell about the nose (no view), or eye turrets any more clearly in any other photo.

I suspect it may be not possible to ID, which is pervserse, because I took some rubbish pics of one with a red body and black legs, and that was no problem to ID.

Thanks for your efforts
Nigel

[Geoff F]

Going by that, I would now suspect either Oligolophus tridens or Lacinius ephippiatus but they are both rather similar; and with legs around 20 mm.

It is only careful close examination of the trident on it's 'nose' which will separate these two. Or microscopic examination of the genitalia!

Incidentally, I took a few photos of what appears to be something similar today. I can just see some trident spines so maybe I will get a positive identification when I examine my photos in detail later.

ps. you might find the harvestman details on this site to be useful http://sites.google.com/site/opilionesuk/

I use the book by P. D. Hillyard - Harvestmen - from the Field Studies Council. No colour photos but useful drawings and ID keys.

[Gateside]

Geoff, that link was really useful.
It will take a time to sort through that. But at the end of the day, it seems I need to get photos of certain parts in exceptional detail (and maybe in future pick one to identify that itsn't like a few others).

Thanks again
Nigel

[Gateside]

I have now looked at the web site suggested by Geoff, and tried sorting through it.

Some of the features I need to check are not visible - I have no proper view of the palps, or a front view head on anyway.

However, I have concluded that it is a Phalangiidae, because the tarsus is longer than the tibia. The legs are not really long enough for a typical Leiobuninae. Also, I think (....!) that there are no denticles on the coxa. (I assume that the key has a spelling mistake here, since it refers to "coaxa", yet no such word is in the glossary, or in my dictionary.)
The legs look remarably smooth, yet what I can see of other Leiobuninae suggests they look rough (hence denticules).
So that places it as a Nelima gothica, which is rare, but never mind. I won't treat that as a reason why not.
It looks overall to be the right shape (very rounded at the rear of the thorax), the leg/body proportions are in the right area, the colours are right, and the marks on the legs - dark distal parts of leg sections match also.

It's not proof, but I can't see a reason why it isn't this, and nothing else fits anyway.

Nigel

[Geoff F]

Without close photos of the necessary areas and an accurate measurement of the second leg length I would be wary of describing this individual as anything other than 'Unidentified Harvestman'.

Overall the body seems a little too long to be a member of the Leiobuninae family; which includes Nelima gothica. And the dark area on the abdomen looks more like a typical 'saddle' than the overall mixture of dark and silvery spots which occur on a typical Nelima gothica. More like a Phalangiidae family member.

Nelima gothica has rather long legs, which may be a little shorter than some Leiobuninae but still reach 40 mm which should be obviously long compared with a body which is a little under 5 mm.

Detailed examination of the coxae are unclear from those photos.

The presence or confirmed absence of a trident on it's 'nose' is essential for a certain identification.

Several members of Phalangiidae also have rather smooth legs and from those images it is impossible to decide whether they are completely round or distinctly angular in section.

For me, it all fits Oligolophus tridens or O. hanseni better than Nelima gothica. But we will never know for sure.

The two people to consult are Gordon or Arp (who used to appear here under the name of 'Pudding for Brains') but unfortunately I haven't seen either of them on this site for a while.

[Gateside]

Geoff, thanks for your comprehensive reply. I agree, it has to be reported as unidentified harvestman. I didn't know at the time what was important to get a clear view of. Never mind - next time I shall know.

Thanks again.
Nigel

[Geoff F]

Incidentally, last week I found my first Dicranopalpus ramosus for this year.

This is one that can be easily identified, although this individual is a strange colour compared with the females which I have previously discovered.