The largest web-spinning spider in the world has been identified, and she’s a terror. The Nephila komaci was discovered in South Africa and displays some rather fascinating characteristics. Its webs, which can reach up to one meter wide, are impressive. But the most striking feature of the spider is its extreme sexual size dismorphism; in plain English, that means the female of the species is dramatically larger than the male.
The average female Nephila komaci is approximately 40 mm long. The male of the species is about one-fifth the size of the female, and is often devoured after inseminating the female. In this pictures, the males are so tiny that it’s hard to believe they are the same species at all. The extreme size difference between the genders isn’t due to small males; rather, it’s due to female gigantism. The females have evolved into their larger size because being big helps them survive longer. Males, on the other hand, get to pass on their genes more effectively if they can climb onto the female to inseminate her, making their smaller size much more desirable from an evolutionary standpoint.
(images via: io9)
Although the species was just formally announced in October 2009, the first known specimen was collected in 1978. It was found in a museum collection some 22 years later, but since no other specimen could be found it was assumed that the spider was either a hybrid, or that the species it belonged to was now extinct. When two females and a male were collected from Tembe Elephant Park in 2009, it became clear that the spider was indeed a new, existing species.