juvenariumとは 意味・読み方・使い方

名詞

juvenarium (plural juvenaria or juvenariums)

1. A shell or portion thereof of a foraminifer in the youngest stage of shell-building.
   • 1959, Walter Leroy Moore, Pennsylvanian foraminifera from the Big Saline formation of the Llano uplift of Texas:

     The earlier figure may be considered to represent this form, for the latter figure is an atypical specimen with multiple juvenaria.

   • 1987, Geologica Hungarica: Series palaeontologica - Volume 51, page 74:

     Later on, the above three genera evolved until various levels of the Eocene in America with unchanged equatorial chamber build-up, but with the microspheric juvenariums becoming more and more simple.

   • 2015, Alfred R. Loeblich Jr., Helen Tappan, Foraminiferal Genera and Their Classification, →ISBN, page 284:

     Test large, subspherical, biumbilicate, inflated, early whorls closely coiled, forming a fusiform juvenarium, later whorls rapidly enlarging in height but coiling axis enlarging more slowly so that adult test becomes globular and strongly umbilicate, final whorl of reduced height as in Pseudoschwagerinal wall of tectum and keriotheca, chomata prominent in the fusiform juvenarium, very faint in later wholrls.