Opilio parietinus - recently moulted subadult female
We had thought this species to have gone completely extinct in the Netherlands but a few years back Jinze Noordijk found a relict population in a tunnel in Limburg and a few month later I found a population on a brick wall under a fly-over of a busy highway smack in the middle of Rotterdam. The population in Rotterdam has now vanished, probably due to graffiti "artists" spraying the wall with paint and some other party cleaning it off later with chemicals and high pressure water.
This image was taken in Rotterdam 2013-07-18 before the population was eradicated.
Same critter zoomed in here:
''Opilio parietinus'' is a species of harvestman. It is found in Europe and North America.
It is similar to ''O. canestrinii'', but has dark spots on its coxae, and is generally more of a grayish green color. Like ''O. canestrini'' it was often found on house walls in central Europe, but has by now almost everywhere been replaced by this invasive species.