Belemnitida, an extinct order of cephalopods commonly known as "belemnites"
Nacre recovered from aulococerids as well as from belemnites resembles that found in recent Sepia and Spirula but differs from that of recent Nautilus.
In turn, belemnites appear to have formed part of the diet of marine reptiles such as Ichthyosaurs, whose fossilized stomachs frequently contain phosphatic hooks from the arms of cephalopods.
The site, whose exact location had not been publicly disclosed, became most famous for squid-like cephalopods and belemnites, complete with their phosphatized soft parts.
According to folklorist Adrienne Mayor, these supposed arrowheads were likely fossil belemnites, which were compared to missiles by other indigenous American cultures, like the Zuni people.
Septum (marine biology): walls between each chamber, or siphuncle, in shells of nautiloids, ammonites, and belemnites; i.e. cephalopods that retain an external shell.