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Danea
From Williams et al., 2017:
[Danea, Morgenroth, 1968, p. 541–542; Emendation: Drugg, 1970b, p.815–816
Danea Morgenroth is not an illegitimate junior homonym of Danaea Smith 1793 as was incorrectly postulated by Fensome et al. (1993b). Names can be considered homonyms only if they are spelled identically, unless conservation or rejection has been formally invoked. See Silva (undated: Index Nominum Algarum).
Type: Danea mutabilis, Morgenroth, 1968 (pl.48, figs.5–6)]
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Original description: [Morgenroth, 1968]: (Translation: Stover and Evitt, 1978, p. 151 (diagnosis); LPP)
Diagnosis:
Object with ellipsoidal to nearly spherical theca.
Tabulation formula(*): (4`), 6``, 6c, 6```, ?2Â, 1````. The plate boundaries are as a rule not prominent and only in exceptional cases are they clearly discernible. The plate areas in general are to be considered as zones formed from groups of processes or membranes whose basal structures follow the plate boundaries. The plate boundaries themselves are situated a certain distance beyond the plate areas.
Cingulum weakly spiral to the left. Generally differentiated by groups of processes. Longitudinal furrow present. Processes can be reduced completely to a short apical and antapical horn. Similarly, the thecal wall can be thickened appreciably. Species of this genus possess a precingular archeopyle.
* (Note by Stover and Evitt, 1978) Morgenroth uses the greek letter `pi` (here indicated with Â) to give the impression that no true tabulation exists.
Affinities:
The new genus possesses the same tabulation scheme as some Gonyaulacysta species. Nevertheless, it must be kept separate from the genus Gonyaulacysta, because the individual plate surfaces bear processes in a characteristic arrangement, which has not yet been observed in Gonyaulacysta.
The new genus differs from from the genus Systematophora Klement, 1960, in which Evitt, 1961 and author could also determine a systematic arrangement of the processes, mainly in the development of a precingular archaeopyle.
The genus Kenleyia Cookson and Eisenack, 1965, also shows a precingular archaeopyle and a girdle region. However, no systematically arranged areas are mentioned by Cookson and Eisenack. The type specimens seem to be so badly preserved, that the arrangement of possibly present process groups can scarcely be determined.
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Emended description:
Drugg, 1970:
Description:
Tract ovoidal with a prominent apical projection an d a somewhat less prominent antapical projection. The archaeopyle is precingular. The epitract exhibits three large annular processes, the central one marking the position of the operculum. At times there are suggestions of additional annular processes. The cingulum is marked by fibrous tabular processes. The hypotract exhibits three large annular processes.
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Modified descriptions:
Stover and Evitt 1978, p. 151-152:
Synopsis:
Cysts proximochorate; body subspherical to ellipsoidal with penitabular septa and discontinuous parasutural septa; apical projection prominent, antapical projection generally short or perhaps absent; archeopyle precingular, Type P.
Description:
Shape: Body subspherical to ellipsoidal with a prominent apical projection and a generally short antapical projection, which may be missing altogether.
Wall relationships: Endophragm and periphragm appressed between septa, or autophragm only.
Wall features: Penitabular septa, discontinuous parasutural septa, and the polar projection(s) fibrous and relatively high; periphragm between septa also fibrous; endophragm (or autophragm) may project into apical projection.
Paratabulation: Indicated most clearly on dorsal surface by penitabular septa, less clearly so on ventral surface where penitabular and parasutural features are close together and may connect. Paratabulation apparently gonyaulacacean, formula: 4`, 6``, 6c, 5-6```, 0-1p, 1````; paraplates on ventral surface not always evident.
Archeopyle: Precingular, Type P (3`` only); operculum free.
Paracingulum: Indicated by a single series of rectilinear, short, transverse, equatorial septa.
Parasulcus: Indicated by several short rectilinear septa, which may connect to form imperfect large-mesh reticulum.
Size: Intermediate to large.
Affinities:
Danea differs from Muratodinium in having a combination of penitabular and parasutural septa rather than parasutural septa only, as is the case with Muratodinium.
[Danea, Morgenroth, 1968, p. 541–542; Emendation: Drugg, 1970b, p.815–816
Danea Morgenroth is not an illegitimate junior homonym of Danaea Smith 1793 as was incorrectly postulated by Fensome et al. (1993b). Names can be considered homonyms only if they are spelled identically, unless conservation or rejection has been formally invoked. See Silva (undated: Index Nominum Algarum).
Type: Danea mutabilis, Morgenroth, 1968 (pl.48, figs.5–6)]
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Original description: [Morgenroth, 1968]: (Translation: Stover and Evitt, 1978, p. 151 (diagnosis); LPP)
Diagnosis:
Object with ellipsoidal to nearly spherical theca.
Tabulation formula(*): (4`), 6``, 6c, 6```, ?2Â, 1````. The plate boundaries are as a rule not prominent and only in exceptional cases are they clearly discernible. The plate areas in general are to be considered as zones formed from groups of processes or membranes whose basal structures follow the plate boundaries. The plate boundaries themselves are situated a certain distance beyond the plate areas.
Cingulum weakly spiral to the left. Generally differentiated by groups of processes. Longitudinal furrow present. Processes can be reduced completely to a short apical and antapical horn. Similarly, the thecal wall can be thickened appreciably. Species of this genus possess a precingular archeopyle.
* (Note by Stover and Evitt, 1978) Morgenroth uses the greek letter `pi` (here indicated with Â) to give the impression that no true tabulation exists.
Affinities:
The new genus possesses the same tabulation scheme as some Gonyaulacysta species. Nevertheless, it must be kept separate from the genus Gonyaulacysta, because the individual plate surfaces bear processes in a characteristic arrangement, which has not yet been observed in Gonyaulacysta.
The new genus differs from from the genus Systematophora Klement, 1960, in which Evitt, 1961 and author could also determine a systematic arrangement of the processes, mainly in the development of a precingular archaeopyle.
The genus Kenleyia Cookson and Eisenack, 1965, also shows a precingular archaeopyle and a girdle region. However, no systematically arranged areas are mentioned by Cookson and Eisenack. The type specimens seem to be so badly preserved, that the arrangement of possibly present process groups can scarcely be determined.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended description:
Drugg, 1970:
Description:
Tract ovoidal with a prominent apical projection an d a somewhat less prominent antapical projection. The archaeopyle is precingular. The epitract exhibits three large annular processes, the central one marking the position of the operculum. At times there are suggestions of additional annular processes. The cingulum is marked by fibrous tabular processes. The hypotract exhibits three large annular processes.
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Modified descriptions:
Stover and Evitt 1978, p. 151-152:
Synopsis:
Cysts proximochorate; body subspherical to ellipsoidal with penitabular septa and discontinuous parasutural septa; apical projection prominent, antapical projection generally short or perhaps absent; archeopyle precingular, Type P.
Description:
Shape: Body subspherical to ellipsoidal with a prominent apical projection and a generally short antapical projection, which may be missing altogether.
Wall relationships: Endophragm and periphragm appressed between septa, or autophragm only.
Wall features: Penitabular septa, discontinuous parasutural septa, and the polar projection(s) fibrous and relatively high; periphragm between septa also fibrous; endophragm (or autophragm) may project into apical projection.
Paratabulation: Indicated most clearly on dorsal surface by penitabular septa, less clearly so on ventral surface where penitabular and parasutural features are close together and may connect. Paratabulation apparently gonyaulacacean, formula: 4`, 6``, 6c, 5-6```, 0-1p, 1````; paraplates on ventral surface not always evident.
Archeopyle: Precingular, Type P (3`` only); operculum free.
Paracingulum: Indicated by a single series of rectilinear, short, transverse, equatorial septa.
Parasulcus: Indicated by several short rectilinear septa, which may connect to form imperfect large-mesh reticulum.
Size: Intermediate to large.
Affinities:
Danea differs from Muratodinium in having a combination of penitabular and parasutural septa rather than parasutural septa only, as is the case with Muratodinium.