
Appearance
Individual spiders' colourings can range from extremely light yellow to very dark grey, but all A. diadematus have mottled white markings across the dorsal abdomen, with four or more segments forming a cross. The markings are formed in cells filled with guanine, which is a byproduct of protein metabolism.Adult females range in length from 6.5 to 20 mm (0.26 to 0.79 in), while males range from 5.5 to 13 mm (0.22 to 0.51 in).

Distribution
A. diadematus has a holarctic distribution, found throughout Europe and across North America, from southern Canada to Mexico, and from British Columbia to Newfoundland.References:
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