macroconch

plural macroconchs · plural macroconches

1. The female form of an ammonite (that has a larger shell than the male (the microconch).

   Initially, the apophysis follows the coiling of the shell but it projects ventrolaterally during the final ontogenetic stage of macroconch development.

   2016 January 14, “Paleobiology of the Latest Tithonian (Late Jurassic) Ammonite Salinites grossicostatum Inferred from Internal and External Shell Parameters”, in PLOS ONE, →DOI

   1 more example

   A few collections of ammonoid eggs have even been found inside macroconchs, which is tempting to interpret as brooding behavior and further support for calling macroconchs female.

   2017, Danna Staaf, Squid Empire, ForeEdge, →ISBN, page 59