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Umbriadinium
From Fensome et al., 2019:
Umbriadinium Bucefalo Palliani and Riding, 1997a, p.199.
This name was not validly published in Bucefalo Palliani and Mattioli (1995, p.60) since these authors did not provide a description.
Type: Bucefalo Palliani and Riding, 1997a, pl.1, fig.1, as Umbriadinium mediterraneense.
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Original description: [Bucefalo Palliani and Riding, 1997]:
Diagnosis:
Proximochorate to chorate, acavate dinoflagellate cysts with up to nine latitudinal rows of paraplates arranged in a suessoid pattern and a combination archeopyle of disintegration type.
Description:
Subspherical to elongate, ellipsoidal, proximochorate to chorate, acavate dinoflagellate cysts. Autophragm smooth or with low relief, surmounted by intratabular processes.May or may not exhibit low parasutural ridges or crests. Processes and parasutural features indicate the presence of up to nine latitudinal rows of relatively small, polygonal paraplates in a suessoid pattern.
Archeopyle combination, involving up to three of the anterior most epicystal paraplate series, compound (i.e. of disintegration type). Paracingulum indicated by an extensive equatorial area which has relatively few spines.
Parasulcus may or may not be indicated by low parasutural ridges or crests.
Discussion/Affinities:
Umbriadinium is similar in paratabulation and shape to the other four genera in the family Suessiaceae. The archeopyle of Umbriadinium is similar to those of Noricysta, Suessia and Wanneria in that all the epicystal paraplate series, except that series immediately anterior to the paracingulum, may be involved in excystment. The operculum of Wanneria is simple (Below, 1987), whereas those of Suessia and Umbriadinium are compound (Morbey, 1975). The archeopyle type of Beaumontella, however, is apical (Below, 1987). A distinction between a simple or compound archeopyle in Noricysta was not made by Bujak and Fisher (1976). The principal difference between Umbriadinium and Noricysta, Suessia and Wanneria is the presence of intratabular (paraplate-centered) processes. These are present in Beaumontella, but as previously mentioned, this genus has an apical archeopyle. Furthermore, Noricysta is cavate. Genera of the family Suessiaceae are compared in Text-Figure 7.
Umbriadinium Bucefalo Palliani and Riding, 1997a, p.199.
This name was not validly published in Bucefalo Palliani and Mattioli (1995, p.60) since these authors did not provide a description.
Type: Bucefalo Palliani and Riding, 1997a, pl.1, fig.1, as Umbriadinium mediterraneense.
---------------------------------------------------------------------------------------------------
Original description: [Bucefalo Palliani and Riding, 1997]:
Diagnosis:
Proximochorate to chorate, acavate dinoflagellate cysts with up to nine latitudinal rows of paraplates arranged in a suessoid pattern and a combination archeopyle of disintegration type.
Description:
Subspherical to elongate, ellipsoidal, proximochorate to chorate, acavate dinoflagellate cysts. Autophragm smooth or with low relief, surmounted by intratabular processes.May or may not exhibit low parasutural ridges or crests. Processes and parasutural features indicate the presence of up to nine latitudinal rows of relatively small, polygonal paraplates in a suessoid pattern.
Archeopyle combination, involving up to three of the anterior most epicystal paraplate series, compound (i.e. of disintegration type). Paracingulum indicated by an extensive equatorial area which has relatively few spines.
Parasulcus may or may not be indicated by low parasutural ridges or crests.
Discussion/Affinities:
Umbriadinium is similar in paratabulation and shape to the other four genera in the family Suessiaceae. The archeopyle of Umbriadinium is similar to those of Noricysta, Suessia and Wanneria in that all the epicystal paraplate series, except that series immediately anterior to the paracingulum, may be involved in excystment. The operculum of Wanneria is simple (Below, 1987), whereas those of Suessia and Umbriadinium are compound (Morbey, 1975). The archeopyle type of Beaumontella, however, is apical (Below, 1987). A distinction between a simple or compound archeopyle in Noricysta was not made by Bujak and Fisher (1976). The principal difference between Umbriadinium and Noricysta, Suessia and Wanneria is the presence of intratabular (paraplate-centered) processes. These are present in Beaumontella, but as previously mentioned, this genus has an apical archeopyle. Furthermore, Noricysta is cavate. Genera of the family Suessiaceae are compared in Text-Figure 7.