Emarginal gains

Posted by Graeme Lyons , Friday, 31 January 2020 14:34

Yes I did just make a word up as a tenuous attempt at a pun. Live with it. Last November I went spidering to the New Forest with Mark Gurney to a National Trust site called Ibsley Common. We found some nice things that had not been seen in the Forest for some time, such as Hypselistes, Taranuncus and Notioscopus. All nice bog species but not much that I hadn't already seen that year. In fact my only year tick I think was Oedothorax fuscus. But I did sweep a smart looking immature Philodromus from Bog Myrtle in a bog under some pines. I became convinced that it was going to be Philodromus emarginatus despite that the fact that I had never seen it. Maybe it was the large flock of Hawfinches that just made you feel like everything there was going to be rare but I had a nagging hunch that I couldn't shift.

Here is the photo of I took in the field at the end of November.

I consulted a few people but knew what the answer was going to be. I needed to get it to adulthood. Further to this Peter Harvey said "I can see nothing much to see emarginatus is a strong contender". So, I HAD to get it to maturity, as I really felt like this was very different to all the Philodromus I had seen before, including the washed out margaritatus that occur at Graffham Common. Perhaps buxi was closest but that was a long way away in London and given that there were two records of emarginatus from the exact same 10 km square, that seemed most likely. Occam's Razor and all that.

I fed the little fella up on springtails from leaf litter in the garden and it did really well, surprisingly reaching adulthood today. The frustrating thing is that the left palp did not come out of the skin when it last shed its skin (it shed its skin twice by the way). So here are some more shots of the nationally rare and Vulnerable Philodromus emarginatus, the 392nd spider I saw last year but the one I can't count either on last year's list, or this year's. Man, this is one gorgeous spider.


Persistence always pays off. Looking at the SRS page it's not been recorded since 2015 and Mark Gurney says the only other records for a National Trust site were from Lavington in West Sussex where it was last seen in 1996. The last Hampshire and New Forest record was from the same 10 km square in 1999. Very cool and the only good thing about the 31st January 2020. Now I wish I had got that female Enoplognatha from Cornwall to adulthood all those years ago but that's another story...

0 Response to "Emarginal gains"

Post a comment

Nature Blog Network