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Achomosphaera mariannae
From Fensome et al., 2019:
Achomosphaera mariannae, (Philippot, 1949, p.56–57; text-fig.2) Stover and Evitt, 1978, p.139.
Holotype: Philippot, 1949, text-fig.2.
Originally Hystrichosphaeridium, subsequently Baltisphaeridium (Appendix A), thirdly (and now) Achomosphaera.
Age: Late Cretaceous.
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Original description: [Philippot, 1949, p. 56-57] (translated from French with Google Translate):
Hystrichosphaeridium mariannae nov. sp. (fig. 2).
Holotype: Silex senonien de Beynes (S.-and-O.). Pers. Coll. N° 123.
Paratype: Silex senonia de Beynes (S.-and-O.). Pers. Coll. N° 123.
The shell is large, spheroidal, globose, with a very slightly chamois surface, dark brown in colour. Its surface bears numerous branched, tight, tortuous, relatively slender processes, arranged “in a bush”. Many of these appendages deviate perpendicularly from the surface of the shell and subdivide into three branches about halfway along their length. Others branch more abundantly and the subdivisions may be closer to the surface of the chamber. The branches are generally flexuous and their distal ends end in the form of small forks.
Dimensions: Shell diameter: about 40 µ.
Length of the longest processes: about 20 µ.
Affinities: This beautiful organism, well characterized, can only be compared to the species Hystrichosphaeridium ramuliferum Defl. It differs essentially from the latter by the shape of the shell, the much greater number of its appendages and the more flexuous and bushy shape of the processes.
Achomosphaera mariannae, (Philippot, 1949, p.56–57; text-fig.2) Stover and Evitt, 1978, p.139.
Holotype: Philippot, 1949, text-fig.2.
Originally Hystrichosphaeridium, subsequently Baltisphaeridium (Appendix A), thirdly (and now) Achomosphaera.
Age: Late Cretaceous.
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Original description: [Philippot, 1949, p. 56-57] (translated from French with Google Translate):
Hystrichosphaeridium mariannae nov. sp. (fig. 2).
Holotype: Silex senonien de Beynes (S.-and-O.). Pers. Coll. N° 123.
Paratype: Silex senonia de Beynes (S.-and-O.). Pers. Coll. N° 123.
The shell is large, spheroidal, globose, with a very slightly chamois surface, dark brown in colour. Its surface bears numerous branched, tight, tortuous, relatively slender processes, arranged “in a bush”. Many of these appendages deviate perpendicularly from the surface of the shell and subdivide into three branches about halfway along their length. Others branch more abundantly and the subdivisions may be closer to the surface of the chamber. The branches are generally flexuous and their distal ends end in the form of small forks.
Dimensions: Shell diameter: about 40 µ.
Length of the longest processes: about 20 µ.
Affinities: This beautiful organism, well characterized, can only be compared to the species Hystrichosphaeridium ramuliferum Defl. It differs essentially from the latter by the shape of the shell, the much greater number of its appendages and the more flexuous and bushy shape of the processes.