Craterella auricula
Schrammen 1910
Craterella auricula is moderately rare at Misburg and Höver. It is slightly more abundant in the Upper than in the Lower Campanian.
The specimen of Craterella auricula shown here is a thick-walled (12 to 25 mm) funnel with conspicuous, large pores and grooves on its outer side.
The second specimen of Craterella auricula is a rather deep funnel with several conspicuous, tear-shaped incisions in its margin. These incisions are quite characteristic for Craterella.
The third specimen of Craterella auricula shown in top view shows the rough internal surface and the large postica inside the paragaster. Notice also the typical grooves and incisions in the funnel rim.
Craterella tuberosa
Schrammen 1901
Schrammen (1910) makes a difference between Craterella tuberosa and Craterella auricula. The former is bowl-shaped with a more shallow paragaster, whereas the latter is more funnel- or ear-shaped. However, in the author's opinion, a sharp distinction is not possible.
The specimen of Craterella tuberosa shown here is a thick-walled, shallow, cup-shaped sponge, with most of its roots preserved.