Pseudo-scorpion

img_7658a

img_7664a-custom(18 Oct 2016) At our first night-walk of this season we found much more than we expected, including this male harvest man (details on page 157 of Green Island in the Sky). At close look we also noticed a tiny reddish thing on its leg: a bit of dirt or a mite (the photo at the right is ‘real life size’!). In gradual enlargements it could be identified as a pseudoscorpion, size 3 mm. We look at its bum, so the pincers are pointing away. Pseudoscorpions live two to three years and were first described by Aristotle. All pseudoscorpions are predators feeding on other invertebrates. They use their pincers to inject venom in their prey, or to cling to larger insects to get a free ride. A pretty rare sighting because of their size, and because they are nocturnal.

img_7659aTechnique
60mm f/2.8 macro lens. With my normal zoom lens this picture would not have been possible as it is not sharp enough. I tried a small aperture of 16, to get enough depth of field. The long exposure of 1/6 was okay because of the frozen posture of both the harvestman and its traveller. ISO 100 is ideal to get as little grain as possible. I don’t like flash light, despite the darkness of the forest. Using a torch, tripod and long exposure gives a good result and maintains the atmosphere of the nocturnal forest. The top photo is a cropped version of the raw original, size 316 x 407 pixels.