(→Turrilitaceae: added Turrilitaceae)
(→Ancylocerataceae: dewikified pending pages -see discussion)
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The Ancylocerataceae are loosely coiled or uncoiled derivitives of [[Late Jurassic]] (
The Ancylocerataceae are loosely coiled or uncoiled derivitives of [[Late Jurassic]] (Tithonian) lytoceratids, some straight or with hook-shaped body chambers, through the ancestral Bochianitidae. The Bochianitidae, which ranges in the Lower Cretaceous stratigraphically into the Lower Aptian, gave rise at the end of the Valanginian, about half way through its range, to the Ancyloceratidae. The Ancyloceratidae in tern gave rise in the Hauterivian to the Hemihoplitidae and in the next to come Barremian to the Heteroceratidae. The Ancyloceratidae has a stratigraphic range that carries it into the Lower Albian, the Hemihoplitidae and Heteroceratidae have much shorter ranges and died out well before.