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Compositosphaeridium
From Fensome et al., 2019:
"Compositosphaeridium", Erkmen and Sarjeant, 1980, p.65–66.
Name illegitimate -- senior homonym: Compositosphaeridium Dodekova, 1974.
Taxonomic senior synonym: Compositosphaeridium Dodekova, by implication in Lentin and Williams (1981, p.53), who included the "type species" of Compositosphaeridium Erkmen and Sarjeant, Compositosphaeridium bulgaricum, in Compositosphaeridium Dodekova. Erkmen and Sarjeant cited the generic name as "Compositosphaeridium Dodekova, 1974" but gave the "type species" as "Compositosphaeridium bulgaricum Erkmen and Sarjeant sp. nov., nom. nov. pro Compositosphaeridium costatum Dodekova, 1974, non Davey and Williams, 1966 [1966b herein] ...." Since a type once designated is permanently attached to a name except through formal conservation (ICN Article 7.2), Erkmen and Sarjeant (1980) effectively and validly published a new generic name, Compositosphaeridium Erkmen and Sarjeant, which is an illegitimate junior homonym of Compositosphaeridium Dodekova.
Type: Dodekova, 1974, pl.1, figs.4–6, text-fig.1, as Compositosphaeridium costatum, designated by Erkmen and Sarjeant (1980, p.67).
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Original description: [Erkmen and Sarjeant, 1980, p. 65-66]:
Genus Compositosphaeridium
DODEKOVA, 1974
1974 Compositosphaeridium DODEKOVA, p. 25-26.
1975 Compositosphaeridium DOD., Lentin & Williams, p. 2148.
1977 Compositosphaeridium DOD., Lentin & Williams, p. 30.
1978 Compositosphaeridium DOD., Stover & Evitt, p. 33.
TYPE SPECIES :
Compositosphaeridium bulgaricum ERKMEN & SARJEANT sp. nov., nom. nov. pro Compositosphaeridium costatum DODEKOVA, 1974, non
DAVEY & WILLIAMS, 1966, Bathonian, Bulgaria.
DISCUSSION :
Chorate dinoflagellate cysts were first reported from the Jurassic by G. Deflandre (1938), who attributed the forms he observed in the French
Oxfordian to the Upper Cretaceous species Hystrichosphaeridium salpingophorum. Almost thirty years later, H. Górka (1965) recorded similar forms from the Oxfordian of Poland; she made no reference to Deflandre's work, but instead proposed a new species, Hystrichosphaeridium polonicum, to accommodate her forms. In a paper already in press at the time, R.J. Davey & G.L. Williams (1966) proposed a further new species, Hystrichosphaeridium costatum, on the basis of material from the English Oxfordian; they tentatively included Deflandre's Jurassic forms in synonymy and pointed out differences between these forms and ,the Cretaceous H. salpingophorum. Subsequently H. Górka (1970) reported the species costatum from the Polish, Callovian, though the forms she illustrated had processes of somewhat larger average size than those described by R. J. Davey & G. L. Williams. She transferred the species to the genus Cordosphaeridium, though noting that the archaeopyle was apical; since it was subsequently demonstrated that typical representatives of that genus have a precingular archaeopyle, this transfer was inappropriate.
In a study of Upper Jurassic dinoflagellate cysts from Roumania, D. Beju (1971) treated H. costaturn as a junior synonym of H. polonicum. However J. K. Lentin & G. L. Williams (1975, p. 2148) disagreed with this conclusion, commenting that H. Górka had not only recognised a difference between the species but had not even thought it necessary to make any comparisons between them. They concluded : "In view of this, only a detailed examination of ,the holotypes of the respective species will resolve the problem. Pending such an investigation, we recommend that both species be retained".
The genus Compositosphaeridium was proposed, after a detailed study of the structure and arrangement of the processes of some forms from the Bathonian of Bulgaria, by L. Dodekova (1974).
These forms have very targe polytubular processes -- processes formed of a cluster of tubes (2-12) -- marking the positions of paraplates and simpler processes marking the cingulum and sulcus. L. Dodekova assigned these forms to the species Hystrichosphaeridium costatum and designated that species as type for her new genus. The allocation of costatum to this new genus was accepted by J.K. Lentin & G.L. Williams (1977) and by L.E. Stover & W. R. Evitt (1978), though its possible identity with polonicum was in both instances noted.
However, in a review of the morphology of Jurassic cysts, W.A.S. Sarjeant (1978, p. 27) raised a different problem, pointing out that there
were considerable differences between the morphology of the Bulgarian Bathonian forms and that of costatum, as visualised by R.J. Davey & G.L. Williams.
A somewhat confused situation has thus developed. In our view, the following points need to be taken into account in any resolution of this situation:
-- The forms assigned to the species costatum by L. Dodekova (1974) do not accord at all closely in morphology with that species, but instead represent a species so far unnamed.
-- The forms assigned to the species costatum by H. Górka (1970) differ hardly at all from typical forms both of that species, as illustrated by R. J. Davey & G. L. Williams, and of polonicum, as illustrated earlier by H. Górka herself.
-- On the basis of published illustrations and descriptions, the species polonicum GÓRKA is a senior synonym of the species costatum.
If the forms used by Dodekova in establishing the characteristics of her genus Compositosphaeridium are placed into a species other than that to which she assigned them, then the species costatum (or its senior synonym polonicum) surely cannot continue to be cited as type for that genus. We therefore here propose that the new species C. bulgaricum, based as it is upon the specimens which Dodekova studied and considered typical of the genus, become henceforward the type species of Compositosphaeridium.
The species polonicum, considered as a senior synonym of costatum, appears to us sufficiently similar in general features to warrant transfer to
the genus Compositosphaeridium, though we do not consider it suitable to serve as type for that genus. The new combination Compositosphaeridium polonicum (GÓRKA) is therefore here proposed and its diagnosis emended. Included into it are both the forms assigned by G. Deflandre to Hystrichosphaeridium salpingophorum and those placed by H. Górka into Cordosphaeridium costatum.
"Compositosphaeridium", Erkmen and Sarjeant, 1980, p.65–66.
Name illegitimate -- senior homonym: Compositosphaeridium Dodekova, 1974.
Taxonomic senior synonym: Compositosphaeridium Dodekova, by implication in Lentin and Williams (1981, p.53), who included the "type species" of Compositosphaeridium Erkmen and Sarjeant, Compositosphaeridium bulgaricum, in Compositosphaeridium Dodekova. Erkmen and Sarjeant cited the generic name as "Compositosphaeridium Dodekova, 1974" but gave the "type species" as "Compositosphaeridium bulgaricum Erkmen and Sarjeant sp. nov., nom. nov. pro Compositosphaeridium costatum Dodekova, 1974, non Davey and Williams, 1966 [1966b herein] ...." Since a type once designated is permanently attached to a name except through formal conservation (ICN Article 7.2), Erkmen and Sarjeant (1980) effectively and validly published a new generic name, Compositosphaeridium Erkmen and Sarjeant, which is an illegitimate junior homonym of Compositosphaeridium Dodekova.
Type: Dodekova, 1974, pl.1, figs.4–6, text-fig.1, as Compositosphaeridium costatum, designated by Erkmen and Sarjeant (1980, p.67).
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Erkmen and Sarjeant, 1980, p. 65-66]:
Genus Compositosphaeridium
DODEKOVA, 1974
1974 Compositosphaeridium DODEKOVA, p. 25-26.
1975 Compositosphaeridium DOD., Lentin & Williams, p. 2148.
1977 Compositosphaeridium DOD., Lentin & Williams, p. 30.
1978 Compositosphaeridium DOD., Stover & Evitt, p. 33.
TYPE SPECIES :
Compositosphaeridium bulgaricum ERKMEN & SARJEANT sp. nov., nom. nov. pro Compositosphaeridium costatum DODEKOVA, 1974, non
DAVEY & WILLIAMS, 1966, Bathonian, Bulgaria.
DISCUSSION :
Chorate dinoflagellate cysts were first reported from the Jurassic by G. Deflandre (1938), who attributed the forms he observed in the French
Oxfordian to the Upper Cretaceous species Hystrichosphaeridium salpingophorum. Almost thirty years later, H. Górka (1965) recorded similar forms from the Oxfordian of Poland; she made no reference to Deflandre's work, but instead proposed a new species, Hystrichosphaeridium polonicum, to accommodate her forms. In a paper already in press at the time, R.J. Davey & G.L. Williams (1966) proposed a further new species, Hystrichosphaeridium costatum, on the basis of material from the English Oxfordian; they tentatively included Deflandre's Jurassic forms in synonymy and pointed out differences between these forms and ,the Cretaceous H. salpingophorum. Subsequently H. Górka (1970) reported the species costatum from the Polish, Callovian, though the forms she illustrated had processes of somewhat larger average size than those described by R. J. Davey & G. L. Williams. She transferred the species to the genus Cordosphaeridium, though noting that the archaeopyle was apical; since it was subsequently demonstrated that typical representatives of that genus have a precingular archaeopyle, this transfer was inappropriate.
In a study of Upper Jurassic dinoflagellate cysts from Roumania, D. Beju (1971) treated H. costaturn as a junior synonym of H. polonicum. However J. K. Lentin & G. L. Williams (1975, p. 2148) disagreed with this conclusion, commenting that H. Górka had not only recognised a difference between the species but had not even thought it necessary to make any comparisons between them. They concluded : "In view of this, only a detailed examination of ,the holotypes of the respective species will resolve the problem. Pending such an investigation, we recommend that both species be retained".
The genus Compositosphaeridium was proposed, after a detailed study of the structure and arrangement of the processes of some forms from the Bathonian of Bulgaria, by L. Dodekova (1974).
These forms have very targe polytubular processes -- processes formed of a cluster of tubes (2-12) -- marking the positions of paraplates and simpler processes marking the cingulum and sulcus. L. Dodekova assigned these forms to the species Hystrichosphaeridium costatum and designated that species as type for her new genus. The allocation of costatum to this new genus was accepted by J.K. Lentin & G.L. Williams (1977) and by L.E. Stover & W. R. Evitt (1978), though its possible identity with polonicum was in both instances noted.
However, in a review of the morphology of Jurassic cysts, W.A.S. Sarjeant (1978, p. 27) raised a different problem, pointing out that there
were considerable differences between the morphology of the Bulgarian Bathonian forms and that of costatum, as visualised by R.J. Davey & G.L. Williams.
A somewhat confused situation has thus developed. In our view, the following points need to be taken into account in any resolution of this situation:
-- The forms assigned to the species costatum by L. Dodekova (1974) do not accord at all closely in morphology with that species, but instead represent a species so far unnamed.
-- The forms assigned to the species costatum by H. Górka (1970) differ hardly at all from typical forms both of that species, as illustrated by R. J. Davey & G. L. Williams, and of polonicum, as illustrated earlier by H. Górka herself.
-- On the basis of published illustrations and descriptions, the species polonicum GÓRKA is a senior synonym of the species costatum.
If the forms used by Dodekova in establishing the characteristics of her genus Compositosphaeridium are placed into a species other than that to which she assigned them, then the species costatum (or its senior synonym polonicum) surely cannot continue to be cited as type for that genus. We therefore here propose that the new species C. bulgaricum, based as it is upon the specimens which Dodekova studied and considered typical of the genus, become henceforward the type species of Compositosphaeridium.
The species polonicum, considered as a senior synonym of costatum, appears to us sufficiently similar in general features to warrant transfer to
the genus Compositosphaeridium, though we do not consider it suitable to serve as type for that genus. The new combination Compositosphaeridium polonicum (GÓRKA) is therefore here proposed and its diagnosis emended. Included into it are both the forms assigned by G. Deflandre to Hystrichosphaeridium salpingophorum and those placed by H. Górka into Cordosphaeridium costatum.