Serrated microstructures on carapaces of Eosestheria (Branchiopoda: Diplostraca) in the Early Cretaceous Jehol Biota and discussion on the taxonomic value of these structures

摘要: Abstract Serrated microstructures on the growth lines of some fossil conchostracans have been previously regarded as a key characteristic for judging family Afrograptidae. Consequently, more than 20 relatively diverse genera were assigned into Afrograptidae based presence serrated structures. This has created series taxonomic disputes in regard to conchostracans. In this study, two species, namely, Eosestheria ovata and E. middendorfii, Early Cretaceous Jehol Biota are reported described detail. Our microstructural study shows that these structures pit-shaped actually insertion remains setae. Such commonly exist extant spinicaudatans. The setae probably served sensory function. or absence species same genus can be variable size also variable. Thus they not appropriate considered possessing important value. Based conclusion, listed conjunction with results our previous study.