Peacock Spider

Maratus volans is one of about 100 described species in the Australian peacock-spider genus Maratus, all 4–5 mm long. The males have evolved an iridescent, brilliantly colored flap on the abdomen — third- or fourth-most-colorful surface ever measured on an arthropod — that they raise like a peacock's tail and wave during precisely choreographed courtship dances. They lift two legs in alternation, vibrate the abdomen at species-specific frequencies, and step in patterns the female evaluates closely. If she accepts, mating proceeds. If she does not, she often eats the suitor. The genus was rediscovered and popularized by entomologist Jürgen Otto, whose macro photography went viral in the 2010s and prompted dozens of new species descriptions in the past decade.