Snow Flea Boreus hyemalis (L., 1767 Mecoptera: Boreidae) in Wyre Forest
Many years ago during the late 1970’s or early 1980’s I recall whilst sitting on a moss covered bank in Wyre Forest partaking lunch spotting a small insect (5mm or so) crawling over a patch of thawing snow. At the time my interests in the smaller insects of the forest was limited but I did check the identity of this creature as it seemed rather unusual. Looking in the ‘Collins Insects book’ by Chinery the insect was described and a line drawing confirmed that it was a snow flea, Boreus hyemalis, (Fig. 1.).
I had forgotten about this old observation until recently when on 2nd December 2009 Jane Scott re-discovered the insect in Wyre in 2011. Following this discovery the Wyre Forest Study Group (WFSG) took up the hunt to locate more (Winnall 2009). My original site was at Longdon Orchard on the Shropshire side of the forest and Jane’s record was at Withybed Woods also Shropshire, so we had no record for Worcestershire from the Wyre Forest.
In Worcestershire Record No. 28. April 2010 Paul Whitehead reported his own observation of snow flea at Swinyard Hill (part of the Malvern Hills) in 1988. Paul suggests that a more apt common name for the insect is ‘Snow Scorpionfly’, which I agree is really a much a better name. Paul remarked that ‘B. hyemalis is a truly localised species in Worcestershire but one that is likely to occur more widely on the Malvern Hills’. I think the same is also true for the acid soils of the Wyre Forest landscape.
So inspired by these recent records the search was on. On a Wyre Forest Study Group meeting on 14th January 2012 we found more B. hyemalis (1 male and 1 female) at Jane’s Withybed Wood site. A few days later on 21st January Denise Bingham found another single female at a new site, but still in Shropshire. On the 23rd January 2012 Denise and I visited Shelf Held Coppice on the Worcestershire side of the Forest, an area of mossy National Vegetation Classification W16 woodland that I felt sure would have B. hyemalis. My hunch paid off and we found several specimens within the mossy woodland floor (four females in total at two sites). The next foray into Wyre was on 28th January when Brett Westwood accompanied us. We looked in Hitterhill Wood and the forest near to Beaucastle, both areas in Worcestershire. Brett found two males at Hitterhill and Denise found one female at Beaucastle(Fig. 2.).
The typical habitat in Wyre Forest appears to be oak woodland, or open woodland glades with a sparse ground flora and areas of bare soil with scattered or extensive clumps of moss such as Polytrichum formosum and/or Dicranum scoparium. This acid woodland type occurs widely in Wyre Forest and also found at sites such as Chaddesley Woods or Hunthouse Wood (Fig. 3.).
Most books suggest both adults and larvae feed on moss but small soil invertebrates seem a more likely food for the adults. Finding B. hyemalis is really a matter of luck, they openly craw over the moss and have a 'metallic sheen' that can catch the sunlight making them easier to find. We found that if after about five minutes looking on a suitable clump of moss it reveals no insects them its best to move on to nearby clump. So as our esteemed editor said in Worcestershire Record No.28 ‘A challenge for next winter is to obtain (more) records in Worcestershire’.
Plant, C.W. 1994. Provisional atlas of the lacewings and allied insects (Neuroptera, Megaloptera, Raphidioptera and Mecoptera) of Britain and Ireland/ Edited for the Biological Records Centre by P.T. Harding, B.C. Eversham and H.R. Arnold. Huntingdon: Biological Records Centre.
Whitehead, P F. 2010. An overlooked Worcestershire insect, the Snow Flea Boreus hyemalis. Worcestershire Record 28:15.
Winnall, R. 2009. Snow Flea, Boreus hyemalis (L.,1767) (Mecoptera: Boreidae). Wyre Forest Study Group Review 2009. 10:42.
Buglife website. February 2012. http://www.buglife.org.uk/discoverbugs/bugofthemonth/snowflea.
Fig. 1. Snow Flea Boreus hyemalis, Longdon, Wyre Forest. John Bingham.
Fig. 2. Snow Flea Boreus hyemalis at Beaucastle, Wyre Forest. John Bingham.
Fig. 3. Snow Flea Boreus hyemalis typical habitat in Wyre Forest John Bingham