Thwaitesia argentiopunctata, the 'mirror- or sequined-spider', native to Australia, has scales coated in guanine, the same as the "G" base in your DNA.
Guanine forms rhomboid crystals with a high index of refraction, making it a biological 'mirror coating'. Sparkly!
(📷: Nicky Bay photography)
c0nc0rdance
🤗 What a spooky disco dancer! Here's your well deserved fly!