A diverse new spider (Araneae) fauna from the Jinju Formation,Cretaceous (Albian) of Korea

Abstract

A collection of spiders from the Cretaceous (Albian) Jinju Formation of Korea is described. These finds increase the number of known spiders from the Jinju Formation from one to 11. There is considerable diversity of mygalomorphs and araneomorphs, including palpimanoids (including lagonomegopids), as well as cribellate and ecribellate entelegynes. Such diversity among so few specimens hints that an even greater range of families will come to light as more specimens are discovered in the future. The first non-amber Lagonomegopidae are described, with the first preservation of a spider eye tapetum in the fossil record, providing evidence for lagonomegopid enlarged eyes being posterior medians. The female-biased sex ratio of lagonomegopids is discussed and it is concluded that the bias is fortuitous.