It about 1-2 mm long. For comparison, a reference picture from http://www.headlice.org/faq/photos.html:
Daniels looks like a nymph to me. Whilst the pictures are a bit yukky, its quite a tribute to the close-up qualities of the nikon 950 that it can take this piccy of something that is pretty hard to see with the naked eye no matter how hard you peer...
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