Orthoconic is simply a descriptive term that translates as straight cone-shaped. On the other side we have to consider the derivation of the term. But the stem of Orthoceras is orthocerat- and the correct form is orthoceratoconic. Many colleagues working on fossil Cephalopoda have a very strong affinity to use endings for superfamilies like -aceae. These endings are for plant families only.
Some people have simply to give up their habits.
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