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Sagenodinium
From Williams et al., 2017:
[Sagenodinium, Williams et al., 2015, p.311–312.
Type species: as Kisselevia crassoramosa, Damassa, 1979a (pl.8,fig.8)] ; Now Sagenodinium franciscanum
Stratigraphic occurrence: Early Eocene
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Original description: [Williams et al., 2015]:
Diagnosis:
Wetzelielloidean cysts with a hyperepeliform archeopyle and a periphragm with processes that are distally trabeculate.
Description:
Shape: Dorso-ventral outline of pericyst rhomboidal, with well-developed apical horn; right antapical horn reduced or absent. Dorso-ventral outline of endocyst ovoidal to quadrate.
Wall structure: Periphragm moderately thick, ornamented with penitabular processes that support a trabecular network. Endophragm moderately thick, smooth to granular.
Pericoels: Cysts cornucavate.
Tabulation: Delineated by trabecular network, which is supported by penitabular processes, and forms simulate complexes.
Archeopyle: Hyperepeliform. Perioperculum free, Endoarcheopyle smaller in size than periarcheopyle, endoperculum free.
Furrows: Both delineated by penitabular processes and trabeculum. The cingulum has a single row of processes.
Size: Large.
Dimensions:
Damassa recorded an overall pericyst length of 121–154 μm, an overall pericyst width of 110–148 μm, an overall endocyst length of 64–105 μm and an overall endocyst width of 62–100 μm.
Affinities/Discussion:
Sagenodinium may be distinguished from other genera with hyperepeliform archeopyles as follows: Rhadinodinium has a pericyst that is smooth or ornamented with features of low relief, Stenodinium has processes that are distally free, and Wilsonidium has conspicuously penitabular to sutural ornamentation. Other genera with trabeculate processes, Michouxdinium, Kledodinium and Sophismatia, may be distinguished on the basis of their archeopyle types: Michouxdinium has a soleiform archeopyle, Kledodinium has a latiepeliform archeopyle and Sophismatia has an equiepeliform archeopyle.
(This genus is based on a new species, Sagenodinium franciscanum, based on specimens that Damassa (1979) assigned to Kisselevia crassoramosa.)
[Sagenodinium, Williams et al., 2015, p.311–312.
Type species: as Kisselevia crassoramosa, Damassa, 1979a (pl.8,fig.8)] ; Now Sagenodinium franciscanum
Stratigraphic occurrence: Early Eocene
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Williams et al., 2015]:
Diagnosis:
Wetzelielloidean cysts with a hyperepeliform archeopyle and a periphragm with processes that are distally trabeculate.
Description:
Shape: Dorso-ventral outline of pericyst rhomboidal, with well-developed apical horn; right antapical horn reduced or absent. Dorso-ventral outline of endocyst ovoidal to quadrate.
Wall structure: Periphragm moderately thick, ornamented with penitabular processes that support a trabecular network. Endophragm moderately thick, smooth to granular.
Pericoels: Cysts cornucavate.
Tabulation: Delineated by trabecular network, which is supported by penitabular processes, and forms simulate complexes.
Archeopyle: Hyperepeliform. Perioperculum free, Endoarcheopyle smaller in size than periarcheopyle, endoperculum free.
Furrows: Both delineated by penitabular processes and trabeculum. The cingulum has a single row of processes.
Size: Large.
Dimensions:
Damassa recorded an overall pericyst length of 121–154 μm, an overall pericyst width of 110–148 μm, an overall endocyst length of 64–105 μm and an overall endocyst width of 62–100 μm.
Affinities/Discussion:
Sagenodinium may be distinguished from other genera with hyperepeliform archeopyles as follows: Rhadinodinium has a pericyst that is smooth or ornamented with features of low relief, Stenodinium has processes that are distally free, and Wilsonidium has conspicuously penitabular to sutural ornamentation. Other genera with trabeculate processes, Michouxdinium, Kledodinium and Sophismatia, may be distinguished on the basis of their archeopyle types: Michouxdinium has a soleiform archeopyle, Kledodinium has a latiepeliform archeopyle and Sophismatia has an equiepeliform archeopyle.
(This genus is based on a new species, Sagenodinium franciscanum, based on specimens that Damassa (1979) assigned to Kisselevia crassoramosa.)