First Fossil Xiphosuran (Chelicerata, Xiphosura) Egg Clutch from the Carboniferous of Khakassia

Resumo

A new formal genus with a new species Xiphosuroides khakassicus gen. et sp. nov. is established for a clutch of nine eggs containing embryos, presumably xiphosurans (Chelicerata, Xiphosura, Bellinurina). This unique specimen comes from the Lower–Middle Carboniferous Sarskaya Formation of Khakassia (Izykhskie Kopi locality). If the hypothesis of the xiphosuran nature of these eggs is correct, the specimen described in this paper is the first certain record of fossil xiphosuran eggs and embryos.