Sheep Tick Ixodes ricinus

For a long time I knew this species as "Deer Tick" but it appears that most relatively serious references call it Sheep Tick. Nevertheless deer are among the carriers, and I imagine the carrier of most of the tick populations in the UK which cause problems for walkers and especially for naturalists who tend to wander off the beaten paths. There is a North American species called Deer Tick that is different (Ixodes scapularis), which may perhaps explain the preference for using Sheep Tick for the species occurring in Britain.

This species may carry Lyme Disease and if you develop any of the symptoms (see the NHS website) following a tick bite you should consult your GP. Friends who have contracted Lyme Disease assure me it is an extremely unpleasant disease and the long term symptoms may be significantly reduced by early treatment - they also advise that you may need to be persistent in order to receive an early diagnosis and prompt access to treatment.

The Bristol University Online Tick ID guide is the best resource I've found for identifying Ixodes ticks - there are a number of similar species. I used this guide to identify the following male which was swept from rushes in the middle of a path through alder carr woodland. For the most part it worked simply enough, but a couple of points were a little more challenging. At couplet 3 the relative width and length of the median place was difficult to determine. There is a diagram with an arrow pointing to the median plate but the width:length ratio does not seem to be very different between the two diagrams for the two options. So I wasn't sure which way to go here, but as Ixodes hexagonus should have a stepped fore tarsus and mine didn't, I took other route. Then at couplet 4 I had another problem deciding if the fore tarsi had a hump or not. My tick's fore tarsi had a distinct bulge on the outer edge which didn't look so different from the hump described and illustrated for Ixodes ventalloi. But this isn't meant to be in East Anglia and I'm not sure the other characters checked out either. Moreover the diagrams for ricinus show the same bulge on the tarsi, so this cannot be what the key was referring to as a hump.

male Ixodes ricinus dorsal and ventral and showing anal plate, palps, fore coxa and fore tarsus, Dillington Carr (Norfolk, UK), 11th April 2022

I can normally get females to a choice between Ixodes ricinus and Ixodes persulcatus fairly easily and if I've interpreted the shape of the genital opening correctly then this is ricinus.

female Ixodes ricinus, Gressenhall (Norfolk, UK), 25th April 2022

As above, this is a straightforward female assuming I've understood the genital opening correctly:

female Ixodes ricinus, Gressenhall (Norfolk, UK), 25th April 2022

It was when examining this one that I started to question whether I had correctly understood the difference between Ixodes ricinus and Ixodes persulcatus. I think I'm getting it right, but comparing with the photos of each species at the Bristol University Tick ID website it's perhaps not quite as clear as I thought it was. Like the ones above, I think this is ricinus but I hope someone will get in touch if you think I'm going wrong. This was swept from bluebells in woodland.

female Ixodes ricinus, Pensthorpe (Norfolk, UK), 15th May 2023

Here's another male that shows tarsus 1 having what looks to me like a marked hump before the tip. Again I think it's ricinus not ventalloi despite this hump - other characters do not fit ventalloi including the size which was 2.4mm long. This tick was swept from a low-hanging pine branch.

female Ixodes ricinus, Snake Wood (Norfolk, UK), 27th May 2023

A female from the same site was swept from low vegetation.

female Ixodes ricinus, Snake Wood (Norfolk, UK), 27th May 2023

I seem to be lucky in that I don't often find ticks attached to me despite spending a great deal of time in tick habitat. This one was an exception. It was quite small and I couldn't find anything that I could clearly identify as the genital opening, so I suspect it was not fully mature. The absence of a genital opening means that I cannot be 100% sure that the ID is correct as the shape of this is a necessary character in the key for females. The alternative possibility is Taiga Tick Ixodes persulcatus but I'm not sure if this is remotely likely.

female presumed Ixodes ricinus (or persulcatus), North Elmham (Norfolk, UK), 20th May 2021

After walking through some woodland where I swept at least two mature female ticks I checked myself carefully for any attached to me. No sign, but despite washing and a complete change of clothes I discovered this small one attached to my belly the following evening. I suppose it's possible I picked it up that day, but that seems a bit unlikely as I spent most of it indoors in Norwich apart from a quick walk down to Tescos to pick up some lunch. Like the last one above, this was small and lacked any evidence of a genital opening, so I can only key it to either Sheep Tick Ixodes ricinus or Taiga Tick Ixodes persulcatus, but I suspect ricinus is far more likely. Both are capable of transmitting Lyme's Disease...

female presumed Ixodes ricinus (or persulcatus) showing underparts including close-up showing fore coxae etc., Norwich (Norfolk, UK), 12th May 2022

The following weren't retained or keyed at all. I don't know how similar other Ixodes look or how likely they are to occur here, but I imagine that they are most likely to be ricinus. The first one turned up in a moth trap - not sure how it got in there unless it attached itself to a moth?!

possible Ixodes ricinus, Cranberry Rough (Norfolk, UK), 1st May 2016

This one was swept from long grass at the edge of a woodland ride.

possible Ixodes ricinus, near Salen (Mull, Argyll & Bute, UK), 1st May 2016