 |
| Dicranopalpus ramosus - A Recent arrival from the Mediterranean |
Love them or hate them, each year as autumn approaches spider
numbers seem to increase dramatically. You certainly see more at this time of
year than any other as adult males are coming out of hiding to seek a mate and as
the temperature drops, both adults and this year’s young start to look for
somewhere to escape the cold of winter.
Over 40 different species have been recorded on the Reserve
and you don’t need to go far to find them. A whole host of species can be found
by simply looking on the outside of the Nature Centre building, where the un-treated
oak frame provides them with a perfect winter hideaway. Whilst most of these species
only come out at night to hunt for their prey, many can be seen resting by day
if you look closely within the space between the wooden panels.
Some of the more commonly encountered species at this time
of year on the Nature Centre building are in fact not spiders at all, but they are
closely related and belong to the same order - arachnidae. These are the harvestmen (sometimes called
‘daddy-long-legs’) and they belong to the family of opiliones – from the latin for ‘shepherd’ (which is thought to
refer to the way that shepherds used to stand on stilts to get a better view of
their flocks). With eight long legs harvestmen look superficially like spiders,
however they do not have true fangs (their ‘fangs’ are more like clasping
claws) and they do not produce silk webs - using only hooks on the ends of
their legs to catch their prey. They differ structurally to spiders in that
they appear to only have a single body section rather than head, thorax and
abdomen. Harvestmen also have only two eyes whereas true spiders have up to
eight.
 |
| Leiobunum rotundum - another regular at Attenborough |
Only three species of harvestmen have ever been recorded on
the Reserve (of the 30+ species recorded in the UK) and one, Dicranopalpus ramosus, can
be readily found on the Nature Centre building during late October. Despite its
relative abundance here at Attenborough this species is quite rare elsewhere in
the UK
(although its range is now spreading). Originally from Morrocco and the Mediterranean,
Dicranopalpus ramosus was first discovered in the south of England in the
1950’s and has slowly spread north. Unlike other species of harvestmen it can
be easily identified from its characteristic resting position with its legs
spread flat out to the side (see photograph).
As with all arachnids in the UK, harvestmen
are often misunderstood and there is an urban myth that they are the most
venomous and deadly of them all. However, with the absence of true fangs and
venom – not to mention small mouthparts that would be unable to penetrate human
skin – this is totally untrue. Like their spider cousins, harvestmen do a
wonderful job of keeping insect numbers low (including pests such as
mosquitoes) and should therefore be loved and not feared.
