Morphoclines of living operculinid foraminifera based on quantitative characters

@inproceedings{Yordanova2004MorphoclinesOL,
  title={Morphoclines of living operculinid foraminifera based on quantitative characters},
  author={Elza K. Yordanova and Johann Hohenegger},
  year={2004}
}
Abstract Growth-independent test characters of the genera Operculina, Planoperculina, and Planostegina were investigated to determine relations to water depth in form of morphoclines. All characters describing test form – thickness, initial vector of the test spiral that is correlated to proloculus size, and radius expansion rate describing test contour – are correlated. The investigated Operculina and Planoperculina species (O. ammonoides, O. elegans, O. complanata, P. heterosteginoides… 

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