Cretaceous sponges from the Campanian of Misburg and Höver

Schrammen 1912

The specimen shown here is probably Aulaxinia fallax, judging from its slender spindle shape and the numerous ostia. The latter are arranged to some degree in rows parallel to the axis, a feature more typical of Aulaxinia sulcifera. The furrows which are characteristic for all Aulaxinia species are not restricted to the stem and the periphery of the paragaster opening, but extend over the full height of the sponge and are fairly narrow.

Roemer 1864

Aulaxinia sulcifera is characterized by its prominent and broad furrows which extend over the whole length of the body. Aulaxinia sulcifera has a tapering stem, but apparently no branching roots. It has a deep and narrow paragaster.

Another example of Aulaxinia sulcifera from the Lower Campanian of Höver.

Roemer, 1841

Aulaxinia ventricosa is the largest among the Aulaxinia species, with heights exceeding 200 mm. It is typically spindle-shaped, but very stout in habit. The furrows are restricted to the lower and upper ends.

The genus Aulaxinia has a skeleton made up of fairly large, smooth tetraclones which unite via zygomes. The dermal scleres are dichotriaenes.

A recently recovered, large specimen of Aulaxinia ventricosa.