Olenecoceras is a genus of Middle Cambrian fossils that, once believed to be a cephalopod, has since been excluded from that group (although no alternative classification has been offered). The genus was established by Zakhar Grigor'evich Balashov in 1966, from the river Olenyok.
See also Vologdinella – another genus named by Balashov, also was formerly believed to be a cephalopod
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