Eostaffella

…
[Systematics, Evolution]
Fusulina separated from small endothyla-type foraminifera in the early Carboniferous period, and evolved rapidly for about 100 million years until they became extinct at the end of the Paleozoic era. At first, lenticular-shaped furna such as Carboniferous Eostaffella were several hundred micrometers in size, but gradually increased in size and changed to spherical, spindle-shaped, and oblong cylindrical shapes, during which time the texture and structure of the walls became increasingly complex. The largest ones, such as Permian Polydiexodina , can reach several centimeters in length.

*Some of the terminology that mentions "Eostaffella" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…
［系統，進化］
　フズリナは石炭紀初期にエンドティラ型の小型有孔虫より分かれ，古生代末に絶滅するまでの約1億年間に急激な進化をとげた。はじめは石炭紀のエオスタッフェラEostaffellaのように数百μmの大きさでレンズ形のものが，しだいに大きさを増し，球形，紡錘形，長円筒形と変化し，この間，壁の組織，構造もしだいに複雑になった。最大のものは二畳紀のポリディークソーディナPolydiexodinaのように長さ数cmに達するものがある。…

※「Eostaffella」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報