A new armigatid fish (Clupeomorpha, Ellimmichthyiformes) from the Lower Cretaceous of northeastern Italy

The abandoned Italcementi Quarry of Vernasso (San Pietro al Natisone, Udine, Friuli Venezia Giulia, northeastern Italy) was opened into the thickest megabed of the Grivò Flysch (megabed no. 11). The megabeds of this unit recorded repeated submarine landslides of large sectors of the margin of the Friuli Carbonate Platform, which collapsed and redeposited in an elongate foredeep basin system during the late Paleocene to early Eocene interval. Some laminated limestone olistoliths, coming from the basal megabreccia of the megabed no. 11 and dating back to the late Hauterivian–early Barremian (Early Cretaceous), yielded an almost neglected fossil ichthyofauna primarily composed of articulated skeletal remains of double-armored herrings (Ellimmichthyiformes). Exquisitely preserved specimens are described in detail herein and assigned to a new armigatid species, Armigatus simonettoi sp. nov. This species is recovered as sister taxon of a clade including the congeneric species A. alticorpus, A. dalmaticus, and A. oligodentatus. The phylogenetic analysis also confirms the monophyletic status of the genus Armigatus. The new double-armored herring species from Vernasso is among the oldest clupeomorph taxa known so far and provides new data to understand the earliest stages of the evolutionary history of the ellimmichthyiform fishes.