Zygadenia is an extinct genus of archostematan beetles from the Early Jurassic to Early Cretaceous. It is considered to be a senior synonym of Notocupes by Kirejtshuk (2020), but other researchers suggest to reserve the genus Zygadenia as a form taxon for isolated elytra that probably belong to the genus Notocupes, while retaining Notocupes as a valid genus for complete body fossils.
Eleven species are included in the genus, after Strelnikova and Yan (2021, 2023). Kirejtshuk (2020) notes that the two Lower Jurassic Australian species Z. westraliensis and Z. martinae possibly merit placement in their own separate genus.
Jurassic species
Hettangian-Sinemurian (201.4 Ma to 192.9 Ma) Xiaomeigou Formation, China Z. dachaidanensis Z. haixiensis
Sinemurian-Toarcian (199.5 Ma to 174.1 Ma) Cattamarra Coal Measures, Australia Z. martinae Z. westraliensis
Tithonian (152.1 Ma to 145.0 Ma) Shar Teeg, Mongolia Z. giebeli Z. handlirschi
Cretaceous species Berriasian (145.0 Ma to 139.8 Ma) Lulworth Formation, United Kingdom Z. angliae Z. tuberculata
Hauterivian (132.9 Ma to 129.4 Ma) Weald Clay, United Kingdom Z. angliae Z. floodpagei Z. simpsoni
Barremian (129.4 Ma to 125.0 Ma) Sinuiju Formation, North Korea Z. liui Weald Clay, United Kingdom Z. angliae Z. floodpagei Z. tuberculata Z. simpsoni
Aptian (125.0 to ~113.0 Ma) Argun Formation, Russia Z. sinitzae Sinuiju Formation, North Korea Z. liui Yixian Formation, China Z. liui Zaza Formation, Buryatia, Russia Z. alexrasnitsyni
Albian (113.0 Ma to 100.5 Ma) Jinju Formation, South Korea Z. cornigera
Notes
References