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Dear Martin, There is information on Leiobunum tisciae in Britain in the SRS News issues 63 (March 2009, numbered p.11), 70 (July 2011, numbered p.19) and 72 (March 2012, numbered p.31), which are available for download on this website at Spider Recording Scheme News. Leiobunum tisciae was a possible reputed mystery species as far back as the middle of the 20th century, but not confirmed until the recent discovery in Scotland by Mike Davidson. Mike or Peter Nicholson, the National Organiser of the HRS, would know if the latest opinion is now that these specimens are definitely L. tiscae or whether there is still some doubt about whether they might be another closely related European species.

Your pictures certainly look as though you must have the species, but you may well find that an actual specimen will be needed to be certain about your harvestman. In any case I suggest you contact Mike for opinion on your photo/s (details in SRS News articles).

Hi all, just registered with your Recording Scheme as I was trying to identify a harvestman I had images of which seems to be Leiobunum tisciae. Can't find much information on it except the other image from its summary. NBN gateway doesn't have any records so is there another distribution map else where?

Images on the Leiobunum tisciae page.

Cheers Martin

Many thanks for the details. Yes, this has to be Opilio canestrini, and I think from the relatively pale leg markings probably still juvenile or freshly moulted. I will add your record to the recording scheme.

Thanks Peter, The insect was seen in my garden, which is at the back of 49 Bolton Lane, Ipswich, Suffolk, IP4 2BX. I think the details (according to an online map at least) are Lat/Lng: 52.061168, 1.159024, OS grid ref: TM166450. The photos (I've added 3 more) were taken on 20 Sept 2012. Regards, Martin

Dear Martin, this certainly looks like Opilio canestrinii to me. Have you got a location, postcode or map grid reference and date for the record?

This is my first posting here, so please forgive any beginner's errors. I am seeking confirmation (or correction) of the species of Harvestman shown in my photo. I have several other photos of the same chap if they would help.

Thanks, Martin

Dear John, many thanks for the details. Look forward to pictures of the spider.

Hello Peter, thanks very much for your response. The site was a small patch of grass verge in the Chilterns (SP8041501733) which is left unmown through the summer for wild flowers. It is on chalk and bordered by gardens and arable fields. There was only this one retreat and I was rather reluctant to take a specimen, but I did take some photos (on film, so there will be some delay in getting them back) which I'll post if they come out. Meanwhile thanks again.

John

This certainly looks likely to be Achaearanea riparia and it is really good to see a picture of the retreat. Locket & Millidge (1951, 1953) states that the female spins long tubular retreat (the entrance opening downwards) which is covered with pieces of twig, grass, stone or earth etc. and Bristowe talks about a huge tent slung in a snare to capture crawling insects (and ants are a speciality). Adults of Achaearanea riparia are usually found in May and June with females into July and occasionally later, so your spider is presumably still around with young because of the extraordinary season we have had this year.

However Achaearanea really need adults under a microscope to identify with reliability and even then they are rather difficult to separate. Whilst it might seem reasonable to assume from the location and position in the habitat that this must be A. riparia, there are other species in Europe which could potentially be present in Britain and for which microscopical examination is needed. We have already had a number of spiders new to Britain recently which would not have been recognised without voucher specimen/s and microscopical examination.

Achaearanea riparia is a scarce spider, so it would be very good to gain definite confirmation of your spider. Can you provide information on the location with grid reference etc.

Could anyone suggest what this retreat might belong to? It was about 5 cm long, 1 cm wide at the entrance and positioned above a Lasius flavus nest. As well as soil from the nest, it had several dead ants incorporated into it. It seems to match the general description for Achaearanea riparia, but I don't know if anything else makes a similar structure? When I found it (18.9.12) it was occupied by a female spider and several young: I haven't been able to get a decent photo of them because of their size, but they did have the high abdomen which is apparently typical of the genus. Any thoughts much appreciated.

John

Thanks Peter,

Ill try to revisit. It was not hard to find. My money is on you being reflex right as usual!

Evan

Dear Marco

The problem with many spiders, and especially most linyphiid spiders, is that there is variation both in adults and even more so potentially in juveniles, and so whilst it may be possible to make educated guesses as to the species from appearance (pattern, colours, size, shape etc) it is ALL TOO EASY to make mistakes, even after a lifetime of experience making preliminary identifications in the field. Without confirmation of identification of genitalia under a microscope (and in quite a few cases where id is especially difficult and even experienced arachnologists can have problems, the opinion of other specialists) then an identification will not be reliable.

It is also necessary to appreciate the very real possibility that there may be other species waiting to be recognised in the British fauna, not necessarily even from the nearby European fauna. We have at least two new examples from recent events this year.

Dear Dan, you need to post a picture to enable any worthwhile comment on what you might have.

Re Any reflex responses for a guide towards ID on this small (3-4mm) spider beaten from heather in a woodland ride I would say it was a Gonatium species, probably (!!) rubens, but could equally well be rubellum if the woodland was ancient.