Spiders in upper Cretaceous Amber from New Jersey (Arthropoda: Araneae)

Abstract

The oldest described fossils of the extant spider families Segestriidae, Oonopidae, Oecobiidae, Dictynidae and Linyphiidae, previously known from the Tertiary, are presented from Upper Cretaceous amber of New Jersey. The third and oldest known specimen of the fossil spider family Lagonomegopidae is also described and provides further palaeontological evidence of a common Laurasian fauna. The extant genera Segestria and Oecobius are taken back a further 52 and 69-74 myr respectively in the fossil record. These fossils predict the presence of the Caponiidae, Tetrablemmidae, Orsolobidae, Dysderidae, Hersiliidae, Eresidae, Pimoidae, Scytodoidea s.I., cyatholipoids, theridioids and symphytognathoids in the Cretaceous. They also extend the known geological range of extant spider families through and beyond the end-Cretaceous extinction. This event, which affected numerous marine and some terrestrial organisms, probably had little effect on the Araneae.