(Collembola: Bilobella braunerae Deharveng 1981)
Written by Pete Boardman
I rather unexpectedly found myself with more time than I would normally have at the start of this year having been made redundant at the end of 2014. I decided to put this time to good use and improve my entomological skills after spending the last decade helping other people improve their biological recording and identification skills through various project officer roles I had held. Also over the past decade I have concentrated on one particular group of insects, the Tipuloidea (craneflies), pretty much at the expense of all other groups, so the time felt right for a bit of entomological diversification.
I decided to try and get to grips with those groups of invertebrates that I had hitherto ignored, or collected and passed to other entomologists to identify. I was also keen to spend more time looking at habitats I had not examined much and this included my own garden. Early in January, because few flying insects are around, I spent some time examining the rotting logs and bark at the bottom of the garden and soon became acquainted with myriapods, isopods, and springtails, all groups I’d not given any thought to before. On a sunny January morning I turned over a piece of bark and noticed there were several very small (approximately 2mm long) bright pink soft-bodied (spring-less) springtails wandering around. As the bark section was small I took it indoors and looked at it under my microscope and was instantly amazed at the diversity of life going about its business. The bark was fissured on the inside which provided an unexpected depth of available space for layers of springtails, very small snails, and mites to wander about in. It reminded me of a 1950’s vision of the future in which flying cars are pictured above the vehicles at road level, such was the amount of biodiversity within this one small bit of habitat that the vast majority of people would not give a second look at.
The pink springtails intrigued me and I reckoned that there were unlikely to be many truly pink species, so I turned to Hopkin (2007) and flipped through this book that had sat unloved in my library since I’d purchased it. I looked through it and the only reference I could find to anything remotely pink was a species that turned up at the Rothampsted Research Station some time back in earthworm beds that was thought to have come from the Philippines, and were now considered extinct in the UK. I decided to email a photograph to Peter Shaw who runs the UK Collembola Recording Scheme to see if he knew what they were and to ask whether pink species were at all common. He got back in touch and asked whether I could send him a specimen which I duly did. After some reflection he contacted me again and asked for another couple of specimens and suggested this species might be of interest. He had been reminded of a paper by Berg (2009) that noted the species Bilobella braunerae Deharveng 1981 from the Netherlands and mapped the European distribution of the species as Italy, Austria, Hungary, Luxembourg, and the Netherlands. Having looked at the Berg paper, Stomp and Weiner (2005) (which detailed the Luxembourg records) and the original paper naming the species by Deharveng (1981) Peter confirmed the identification of “my” springtails as this species and therefore new to the United Kingdom.
I say “my” springtails because the next thought was “why here?” and “how?” We live in the heart of Shropshire, in a rural location which is generally unremarkable in terms of new UK species turning up. The Berg paper highlighted the habitat of the springtail as exactly that in which I had found it at home, rotting timber. The timber in question was a slice of old tree that had been given to me by my father (based in Cheshire) to make a seat or table top out of but in the age old manner of “I’ll get around to it one day-ness” that many of us live by, it had remained where it was put on arrival around 18 months previously. In that time the bark had gradually dropped off the edges and I’d piled it up together as habitat for whatever wanted to use it. So had the springtails come in 18 months ago with this timber slice? I cast my net wider to other piece of rotting timber on our property, a tree stump that had been placed on a manhole cover for the septic tank system in our car parking area to protect it from being driven over. The log had gradually rotted over the 4 years of our tenancy and could only loosely still be described as a log at all, with most of it nearer soil than timber in its state of decay. I lifted up those pieces still intact and sure enough several “pinkies” were minding their own business here also. So were they here first and migrated across to the timber slice to take up residence in the bark that had fallen off? This seems fairly likely and probably takes the colonisation of rotting timber back before we arrived at this property, unaware that a new species to the United Kingdom was lurking awaiting discovery. Certainly the estate agent didn’t mention it in the property information at the time!
So the mystery remains. Where did Bilobella come from? Where else does it lurk? (for surely it must discretely be wandering around on the underside of rotting bark elsewhere in the UK)? Presumably it is just a matter of time before someone else finds the pinkie at another location and my moment of glory fades from the memory of all who read about it, but I reserve the right to enjoy it whilst I can and it has taught me a few entomological lessons; 1) even the most mundane and every day of habitats can produce the most interesting of finds! 2) You don’t have to travel far and wide to find beauty and interest in the natural world. 3) The perception is that the academic world is at arm’s length away from the everyday entomologist – not a bit of it, the people who helped me to identify and confirm my new discovery were incredibly helpful and generous with their time. 4) Your eyes are your best tool as an entomologist / naturalist. Finally 5) A reaffirmation that there is so much out there for people to find, new species and new observations of behaviour of species we have already classified but don’t necessarily know a great deal about, so anyone can truly make a difference.
Acknowledgements
I must wholeheartedly thank Peter Shaw of Roehampton University who runs the UK Collembola Recording Scheme, Frans Janssens of the University of Antwerp who runs the Checklist of World Collembola at www.collembola.org, and Matty Berg of the University of Amsterdam who kindly supplied the papers I mentioned in the text.
References
Berg, M.P. 2009 – De springstaarten van Nederland: Het genus Bilobella, Nieuw voor de fauna, en Neanura (Hexapoda: Entognatha: Collembola). Nederlandse Faunistische Mededelingen – 31.
Deharveng 1981 – Nouvelles Espices de Neanurinae Europeens appartenant aux genres Bilobella et Monbella. Extrait du Bulletin de la Societe D’Histoire Naturelle de Toulouse T.117, Fasc. 1-2-3-4.
Hopkin, S.P. 2007 – A Key to the Collembola (Springtails) of Britain and Ireland. Aidgap, Field Studies Council. Shrewsbury.
Stomp, N. and Weiner, W.M. (2005) – Some remarkable species of Collembola of the Luxembourg sandstone. Ferrantia. 44. p227-232