Jeletzkya douglassae is a fossil belemnoid from the early Pennsylvanian Mazon Creek lagerstätten and represents the earliest known crown-group squid. Non-mineralized anatomy is preserved and comprises ten hooked tentacles and a radula. It is too poorly understood for assignment to any particular cephalopod taxon. In 2026, it is considered as a synonym of Saundersites illinoisiensis. It had shell about long.
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