Tuesday, 11 October 2016

4th Record For Cryptachaea blattea in the UK

On the evening of the 16th Sept 2016 I was in my garden, headlamp on, checking the Nigma puella spiderlings on the buddleia, scanning amongst the flowerbeds, the usual stuff us arachnid enthusiasts get up to. After about a hour I called it a night and headed indoors. On the way in, my torch shone on a spider travelling along a silk line from my conservatory to a fence. As usual, I had no collecting tubes on me and ran indoors to pick up a container. When I got back outside, it took me probably 5 minutes to locate the spider again. I collected the specimen, had a quick look under a hand lens and assumed it was a male Parasteatoda sp. It wasn't until the following morning that I had a proper look at a very small male adult spider and started to doubt my original assumption of Parasteatoda species. I'm not an expert when It comes to identification but something didn't look right. I took some photos which weren't easy due to it's size and the fact it wouldn't play the game and smile for the camera! I posted them on some forums and and social media and a few suggestions were thrown at me, Cryptachaea sp. being the most obscure. I checked SRS for Cryptachaea sp. and saw that there was one species showing on the mainland, Cryptachaea blattea and then I got goosepimples!! This spider had only been recorded three times in the UK and am I really to believe that one has virtually dropped into my lap. It was maybe a couple of days later, after I had dismissed any thoughts that my mystery spider was a C.blattea, that I posted my photos to Matt Prince via Twitter. Matt is the area organiser for VC 3 and 4 and replied to my photos fairly sharpish. He's response was a bolt from the blue! "Is that a tubercle on it's back?" To which I replied, "what, are you thinking, Ero species? this spider is lacking the distinctive leg spines of Ero species" and finally Matt dropped the bomb, " nah, Cryptachaea " Now, if you don't know, Matt found one of the previous Cryptachaea blattea's, in Plymouth I believe. So I sent my specimen off to Matt and waited in anticipation and stressing that the Royal Mail wasn't going to let me down. After what seemed like a lifetime (hmm, does that sound dramatic) I received a tweet from Matt and I was a very happy chappy. My mystery spider was indeed a Cryptachaea blattea and only the 4th record for the UK.

Sunday, 25 September 2016

Lunch For Two??

Ero aphana are commonly known as pirate spiders for their araneophagic habits and I've spent a few years now observing this species and feel like we are old friends. In May this year I managed to photographed a male and female sharing prey, a behaviour that has never been photographed before, mainly due to the fact this is a tiny nocturnal species that hides during the day. So a couple of days ago I found an immature male and female specimen and put them into an enclosure. This species are fairly tolerant of each other but I have observed a female eating a male so my fingers were crossed that the female was going to behave herself. The next night I collected a Platnickina tincta, another notorious spider hunter, and introduced it into the enclosure and then waited. It was over an hour before the female Ero aphana made the kill, slowly stalking it's prey before she was near enough to rush in and bite her victims leg and killing it nearly instantaneously. While the female feeds on the P.tincta, the male Ero aphana starts to stir and slowly makes his way to the banquet. He stops underneath the female and waits, and doesn't he wait! For over a hour he hangs motionlessly. When he does eventually more, the process is excruciatingly slow. For nearly three hours I watched this little fella move a few millimetres! So after what seemed like an eternity, he is within in biting distance and you know what, she dropped it, basically threw the dog a bone and him, like a good puppy ran after it. Ok, he didn't run, more of a leisurely walk.

Wednesday, 24 August 2016

Hunting behaviour of Hogna lenta.

Hogna lenta is an ambush predator. They emerge at night from their burrows and wait and wait and wait. Eventually some unsuspecting critter (in this case a cricket) will stroll on by, going about it's business, and pass within striking distance of this tiger of the invert world and BOOM.... Hogna lenta leaps onto it's prey, they roll and she is on her back with the cricket on top of her, but that is just fine, as in this position the cricket is helpless, its powerful legs having no ground to purchase. Hogna lenta stays in this position for nearly 10 seconds, allowing her venom to take effect before flipping over in an instant, to dine at her leisure.


Sunday, 21 August 2016

Dysdera crocata (Woodlouse Hunter)

A lot of the spiders I collect in the field are photographed in a white tray and I use a small fine paintbrush to position them. In the UK we have very few arachnids capable of giving a painful bite and Dysdera crocata, with its impressive fangs, is one of them. This female wasn't at all happy with me touching her and immediately spun around to bite the paintbrush. Interestingly, Segestria florentina, another one of the UK's 6 eyed spiders is equally defensive. For the record, this is defensive behaviour. I'm sure if someone poked me with a broom, I'd soon get the hump!


Sunday, 31 July 2016

Pisaura mirabilis with six legs.

Pisaura mirabilis (Clerck, 1757)
If a spider is injured on the abdomen, it usually amounts to a death sentence. Spiders have an open network which means its arteries carry haemolymph, the arthropod equivalent of mammalian blood, out into the tissue spaces where it diffuses past individual cells before being collected back into the heart. There are few, if any, veins in this system and definitely no capillaries. So if there is an injury which causes an opening in the side of the body, this fluid leaks out and the animal dies. Losing a leg or two is a different ball game altogether. At the joints of the legs the spider has sphincters which close off therefore saving the spider from bleeding to death.

Friday, 22 July 2016

Matriphagy and A.similis.

Matriphagy is well documented in the species of lace web spider, Amaurobius ferox, but I can find no documentation on the UK's other 2 species practising this behaviour. On the 18/6/16 I found this female Amaurobius similis and retained her for observation. One thing that has stood out is the size of the females abdomen after producing such a large egg sac. The black lace web weaver, A.ferox is known to produce a second clutch of eggs for her young to feed on before ultimately consuming her. Is this going to be the case with this female A.similis? The first spiderlings started to emerge on the 13/7/16.
21/07/16 UPDATE: Before work, I checked on the female and she was very much alive. She was still very large and healthy looking but when I returned from work this evening, the case for A.similis and matriphagy was proven. The spiderlings had mainly consumed her abdomen, which makes sense but also one leg was eaten. The engorged spiderlings were released under my garden hedge never realizing the ultimate sacrifice that their mother paid so they can receive a fighting start in life.

Female Amaurobius similis with egg sac.

The first spiderlings start to emerge.

Spiderlings are continuing to emerge but still many more in the egg sac.

All the spiderlings seem to have left the sac.

21/07/16 AM
The female is very much alive.

21/07/16 PM
I returned from work and found the conclusive proof that Amaurobius similis practise matriphagy. Abdomen has been completely consumed but note that leg I has also been eaten up to the femur.

21/07/16 PM
I returned from work  and found the conclusive proof that Amaurobius similis practise matriphagy.

Saturday, 27 February 2016

Zoropsis spinimana, a newcomer to the UK

I'm an admin on a very successful facebook group called British Spider Identification that was started by the lovely Jenni Cox. Anyway a several days ago, a lady posted a photo of a distinctive looking spider that she had found in her garden shed in Richmond, Surrey. Straight away it was identified as a Zoropsis spinimana. This is a large, heavy set, slow moving spider, (by UK standards, that is), that doesn't build a web but actively hunts its prey. Traditionally a Mediterranean species, Zoropsis spinimana has established itself in the USA and UK. Most records for this species in the UK have been in London and the outlying areas. Anyway, after the photo was posted in the group, I got in contact with the lady (her names Sue) and asked her if she could send me the specimen. Sue sent it the following morning and I received it the following day. When I got in from work later that day, I must say I was like a kid in a sweet shop, proper excited to say the least. I open the parcel and wasn't disappointed! She is quite a large specimen at 31mm body length and nearly 2 inch leg span. Her abdomen is absolutely massive, so there's always the possibility of her being gravid. I took her out for a few quick photos and to be fair, they were quite rushed as she was very sluggish and and obviously stressed by her Royal Mail trip, special delivery class! I've now had her for a few days and she has livened up no end. Very docile species and walks with a tarantula gait, and I'm chuffed to have her in my collection.
This was the photo that was posted on the Facebook
group British Spider Identification by Sue.

This photo shows the eye arrangement, though the PLEs aren't very clear.

The beautiful carapace markings of Zoropsis spinimana.

Dorsal view 

Handling this very docile species.