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Baltisphaeridium
From Williams et al., 2017:
[Baltisphaeridium Eisenack, 1958a, p. 398–399; Emendations: Staplin et al., 1965, p. 188; Eisenack, 1969b, p. 249; Eiserhardt, 1989, p. 88–90.
Acritarch genus.
Although the "type species", Baltisphaeridium longispinosum, was not validly transferred by Eisenack (1958a, p.398), the generic name Baltisphaeridium was validly published since it is based on a previously validly published specific name (I.C.N. Article 40.3). For synonymy see Fensome et al. (1990, p.82–83).
Type species: originally as Ovum hispidum subsp. longispinosum, Eisenack, 1931 (pl.5, fig.10)] ; Baltisphaeridium longispinosum, Eisenack, 1959
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Original description: [Eisenack, 1958a, p. 298-399] (translated from German):
Genus Baltisphaeridium n.g.
Diagnosis: Hystrichospheres with a spherical to oval, unfielded central shell and with +/- numerous, usually well-set, unbranched or branched, hollow and generally similar, closed appendages (which are therefore not open at the end or even expanded like a funnel).
The type of the genus is B. ["Hystrichosphaeridium"] longispinosum (Eisenack 1931).
It will not always be easy to decide whether the appendages are closed at the end or not for the species that belong to Baltisphaeridium. The best way to do this is to observe them when embedding them in Canada balsam, and it is not difficult to see where the air is being displaced by the balsam.
The majority of Silurian hystrichospheres belong to Baltisphaeridium, which is why a Silurian species was chosen as the genotype, namely from the Baltic region, which is expressed in the name. I will return to the extent and species of this genus when dealing with such Silurian forms.
[Baltisphaeridium Eisenack, 1958a, p. 398–399; Emendations: Staplin et al., 1965, p. 188; Eisenack, 1969b, p. 249; Eiserhardt, 1989, p. 88–90.
Acritarch genus.
Although the "type species", Baltisphaeridium longispinosum, was not validly transferred by Eisenack (1958a, p.398), the generic name Baltisphaeridium was validly published since it is based on a previously validly published specific name (I.C.N. Article 40.3). For synonymy see Fensome et al. (1990, p.82–83).
Type species: originally as Ovum hispidum subsp. longispinosum, Eisenack, 1931 (pl.5, fig.10)] ; Baltisphaeridium longispinosum, Eisenack, 1959
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Original description: [Eisenack, 1958a, p. 298-399] (translated from German):
Genus Baltisphaeridium n.g.
Diagnosis: Hystrichospheres with a spherical to oval, unfielded central shell and with +/- numerous, usually well-set, unbranched or branched, hollow and generally similar, closed appendages (which are therefore not open at the end or even expanded like a funnel).
The type of the genus is B. ["Hystrichosphaeridium"] longispinosum (Eisenack 1931).
It will not always be easy to decide whether the appendages are closed at the end or not for the species that belong to Baltisphaeridium. The best way to do this is to observe them when embedding them in Canada balsam, and it is not difficult to see where the air is being displaced by the balsam.
The majority of Silurian hystrichospheres belong to Baltisphaeridium, which is why a Silurian species was chosen as the genotype, namely from the Baltic region, which is expressed in the name. I will return to the extent and species of this genus when dealing with such Silurian forms.