Opis

Kołnierzyki syfonalne dłuższe od komór powietrznych fragmokonu

Very long septal necks coming close to or even intruding the preceding septum;
cylindrical, ventral siphuncle filled in its apical part with diaphragms and calcareous deposits of "cone-in-cone" structure (endocones).
Long septal necks make the Endoceratina different from their ancestral Ellesmeroceratina as well as from all the other primitive nautiloids. The complete separation of the siphon from the chambers by the imperforate neck made cameral liquid exchange probably difficult, causing the absence of cameral deposits.

Synonimy
endocerasy

Zasięg czasowy

Literatura