Cretaceous sponges from the Campanian of Misburg and Höver

 

Balantionella elegans

Schrammen 1902

Figure 1 - Balantionella elegans, oblique view.
Alemannia, Höver, basiplana Zone


Figure 2 - Balantionella elegans, bottom view.
Alemannia, Höver, basiplana Zone


Figure 3 - Balantionella elegans, side view.
Alemannia, Höver, basiplana Zone


Synonyms:

none

 

Occurence:

Alemannia, Höver, Lower Campanian (senonensis zone). Very rare.

Misburg, Lower Campanian. Very rare.

Oberg, Lower Campanian. Very rare.

 

Balantionella elegans was described by Schrammen (1902) from Misburg and Oberg as a new species. Later, Schrammen (1912) errected the new family Balantionellidae.

Schrammen's (1912) description suggests an incrusting mode of occurrence. However, in the light of the new specimen presented here in Figures 1, 2 and 3, it is obvious that Balantionella elegans must have had a tubular to funnel-like habit, with numerous radial protrusions of the side wall. These protrusions have bag-like (Schrammen, 1912) shapes, with parieral oscula along their edges.

The new specimen from Höver is a midle section, without a preserved top margin or base.

The dermal side reveals numerous tiny ostia, 0.2 to 0.3 mm wide, which are arranged in subparallel to fan shaped arrays.

Figure 4 - Balantionella elegans, etched samples.
(From Schrammen 1912, Table XXX, Fig. 5)


Microstructure:

Figure 4, reproduced from Schrammen (1912), shows two etched fragments of Balantionella elegans. The linear arrangements of epirhyses on the sides walls of the bag shaped protrusions are clearly visible.

The same skeletal structure is found in the new specimen from Höver. The dictyonal skeleton is composed of an essentially cubic meshwork of hexactines. On the dermal surface, additional interspersed, randomly oriented hexactines fill the quadratic meshes of the dictynal skeleton. Locally (mainly near the margins of the parietal oscula) a dermal layer of silica mantled, random hexactines with enlarged globular nodes is preserved.


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