Mongolarachne

Mongolarachne is an extinct genus of spiders placed in the monogeneric family Mongolarachnidae. The genus contains only one species, Mongolarachne jurassica, described in 2013, which is presently the largest fossilized spider on record. The type species was originally described as Nephila jurassica and placed in the living genus Nephila which contains the golden silk orb-weavers. Subsequently, it was determined to be stem-orbicularian, i.e. a relative of the group Orbiculariae, which contains the family Nephilidae, but also several other families, such as Theridiidae, Theridiosomatidae or Uloboridae. The species is known only from the Middle Jurassic Jiulongshan Formation, part of the Daohugou Beds, near the village of Daohugou in Ningcheng County, northeastern China. A second putative species, Mongolarachne chaoyangensis, was described in 2019, but it was subsequently shown to be a forgery based on a fossil crayfish. Jorg Wunderlich placed Longissipalpus and Pedipalparaneus from the Cenomanian aged Burmese amber into Mongolarachnidae in 2015.