This convergence is an unexpected trend [ 26 ] as S . spirula has the simplest septal morphology: a semi-hemispherical dome-shaped structure, compared to the multi-lobed septa of Kosmoceras sp.
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This convergence is an unexpected trend [ 26 ] as S . spirula has the simplest septal morphology: a semi-hemispherical dome-shaped structure, compared to the multi-lobed septa of Kosmoceras sp.