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Phallocysta
From Williams et al., 2017:
[Phallocysta, Dörhöfer and Davies, 1980, p. 26–27; Emendations: Riding, 1984b, p. 117, 119; Below, 1987a, p. 132.
Type species: Phallocysta eumekes, Dörhöfer and Davies, 1980 (fig.26K (not 29K))]
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Original description: [Dörhöfer and Davies, 1980]:
Diagnosis:
Proximate dinoflagellate cysts; elongated, tapering apically with two large antapical hemispherical protuberances. Phragma two layered, surface smooth or bearing low but variable ornament. Phragms of epitract thin; phragms of hypotract thickened. Tabulation 4`, 5a, 6``, ?6c, 6```, ?````; archaeopyle 3I.
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Emended descriptions:
Riding, 1984:
Diagnosis:
Proximate, epicavate dinoflagellate cysts, subtriangular in outline, with a distally-tapering apical horn. Surface of periphragm smooth to granulate, endophragm smooth. Paratabulation not indicated, except by archaeopyle.
Archaeopyle intercalary, Type I, 2I or 3I (number of paraplates involved in archaeopyle formation obscure).
Affinities:
Phallocysta differs from Wallodinium Loeblich and Loeblich, 1968, in having an intercalary archaeopyle and from Pareodinia Deflandre, 1947; emend. Stover and Evitt, 1978 and Susadinium Dörhöfer and Davies, 1980, by being epicavate.
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Below, 1987: (Translation: after Translation Bureau of the Secretary of State, Canada. p. 333)
Diagnosis:
Arrangement of vesicles/plates on the dinoflagellate amphiesma cop, pop, cap, 5`, 3a, 7``-6``, 7c, 5```, 2````, as, y, z, ps; 1```` and 2```` located symmetrically on either side of the dorsoventral plane.
Cyst habit proximate, proximochorate, chorate, acavate-cavate, iso or oblong spheroidal, ovoidal, ovaloidal, peridinoidal, equatorial cross-section lenticular, reniform, oval, circular, with/without polar processes, size variable; wall composed of pedium, also with luxuria; surface smooth, ornamented, nonareate, areate, surface marked by finate ornaments, limbi, or intraareate ornamentation; areation NR PR/cop, pop, cap, NR`/5`, NRa/3a, NR``/7``-6``, NRc/7c, NR```/5```, NR````/2````, NRs/as, y, z, ps; archaeopyle anterioir intercalary, 1a+2a+3a; operculum triareate, solvate, opercular pieces secate, general opercular formula 1a(s)+2a(s)+3a(s).
Affinities:
Also Andreedinium has a triareate operculum. However, the opercular pieces are adnate to the precingular areae. Hebecysta, on the other hand, ejects all three anterior intercalaries, but preferentially only 2a. But the areation of the hypocyst of Hebecysta is unknown.
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Modified description:
Stover and Williams 1987, p. 177:
Synopsis: Cysts proximate, epicavate, overall shape somewhat conical with an elongate anterior part; periphragm smooth or ornamented with features of low relief; archaeopyle types I, 2I or 3I.
Description:
Shape: Somewhat conical with an elongate anterior epicyst; hypocyst may be lobate posteriorly.
Wall relationships: Cysts epicavate, epicoel prominent; endocyst occupies nearly all of the hypocyst.
Wall features: No parasutural features; periphragm smooth or with features of low relief; endophragm smooth.
Archaeopyle: Type I, 2I or 3I; operculum typically detached, composed of 1 to 3 elongate anterior intercalary paraplates.
Paratabulation: Indicated by archaeopyle only.
Paracingulum: Not indicated.
Parasulcus: Not indicated.
Size: Small to intermediate, length about 40-65 µm
Affinities:
Phallocysta differs from Pareodinia Deflandre 1947 emended Stover and Evitt 1978 in being cavate.
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Riding 1994, p. 13:
Remarks/Affinities:
The emendations of both Riding (1984) and Below (1987) are cited here. Riding (1984) stressed the consistently epicavate nature of this genus and described the subspherical, antapically-positioned endocyst. These features were not mentioned in the later emendation by Below (1987), which focused principally on the paratabulation.
Junior Synonym. Andreedinium Below 1987.
The genus Andreedinium Below 1987 differs only from Phallocysta in having adnate, as opposed to free, opercular pieces; these genera have identical shapes, sizes, cyst organizations, paratabulations, archeopyle paraplate equivalence, ornamentation and stratigraphic distributions. The anterior intercalary paraplates of Andreedinium arcticum Below 1987 (the type species) are adnate posteriorly to the precingular series. In the view of the author, this relatively minor difference does not warrant the retention of two otherwise identical genera, especially when preservation dictates that the distinction is frequently difficult to discern using the transmitted light microscope. Thus Andreedinium is herein deemed to be a junior synonym of Phallocysta. This means that the archeopyle type of Phallocysta is anterior intercalary, the compound opercular pieces are adnate posteriorly or free (type 3Ia or 3I).
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Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Phallocysta Dörhöfer and Davies, 1980, emend. Riding, 1984b, emend. Below, 1987a. Below (1987a, p.132) emended the diagnosis as follows. Arrangement of plates on the dinoflagellate amphiesma cop, pop, cap, 5`, 3a, 7"-6", 7c, 5"' , 2"' , as, y, z, ps; 1"' and 2"' located symmetrically on either side of the dorsoventral plane. Cyst habit proximate, proximochorate, chorate, acavate-cavate, sio or oblong spheroidal, ovoidal, avaloida, peridinioidal, equatorial cross section lenticular, reniform, oval, circular, with or without polar processes, size variable; wall composed of pedium, also with luxuria; surface smooth, ornamented, nonareate, areate, areae marked by finate ornament, limbi, or intraareate ornamentation; archeopyle anterior intercalary 1a + 2a + 3a; operculum triareate, solvate, opercular pieces secate, general opercular formula 1a + 2a +3a. According to Feist-Burkhardt 1994), this genus has a type 3I archeopyle with an adnate operculum.
[Phallocysta, Dörhöfer and Davies, 1980, p. 26–27; Emendations: Riding, 1984b, p. 117, 119; Below, 1987a, p. 132.
Type species: Phallocysta eumekes, Dörhöfer and Davies, 1980 (fig.26K (not 29K))]
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Original description: [Dörhöfer and Davies, 1980]:
Diagnosis:
Proximate dinoflagellate cysts; elongated, tapering apically with two large antapical hemispherical protuberances. Phragma two layered, surface smooth or bearing low but variable ornament. Phragms of epitract thin; phragms of hypotract thickened. Tabulation 4`, 5a, 6``, ?6c, 6```, ?````; archaeopyle 3I.
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Emended descriptions:
Riding, 1984:
Diagnosis:
Proximate, epicavate dinoflagellate cysts, subtriangular in outline, with a distally-tapering apical horn. Surface of periphragm smooth to granulate, endophragm smooth. Paratabulation not indicated, except by archaeopyle.
Archaeopyle intercalary, Type I, 2I or 3I (number of paraplates involved in archaeopyle formation obscure).
Affinities:
Phallocysta differs from Wallodinium Loeblich and Loeblich, 1968, in having an intercalary archaeopyle and from Pareodinia Deflandre, 1947; emend. Stover and Evitt, 1978 and Susadinium Dörhöfer and Davies, 1980, by being epicavate.
----------------------------------------
Below, 1987: (Translation: after Translation Bureau of the Secretary of State, Canada. p. 333)
Diagnosis:
Arrangement of vesicles/plates on the dinoflagellate amphiesma cop, pop, cap, 5`, 3a, 7``-6``, 7c, 5```, 2````, as, y, z, ps; 1```` and 2```` located symmetrically on either side of the dorsoventral plane.
Cyst habit proximate, proximochorate, chorate, acavate-cavate, iso or oblong spheroidal, ovoidal, ovaloidal, peridinoidal, equatorial cross-section lenticular, reniform, oval, circular, with/without polar processes, size variable; wall composed of pedium, also with luxuria; surface smooth, ornamented, nonareate, areate, surface marked by finate ornaments, limbi, or intraareate ornamentation; areation NR PR/cop, pop, cap, NR`/5`, NRa/3a, NR``/7``-6``, NRc/7c, NR```/5```, NR````/2````, NRs/as, y, z, ps; archaeopyle anterioir intercalary, 1a+2a+3a; operculum triareate, solvate, opercular pieces secate, general opercular formula 1a(s)+2a(s)+3a(s).
Affinities:
Also Andreedinium has a triareate operculum. However, the opercular pieces are adnate to the precingular areae. Hebecysta, on the other hand, ejects all three anterior intercalaries, but preferentially only 2a. But the areation of the hypocyst of Hebecysta is unknown.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:
Stover and Williams 1987, p. 177:
Synopsis: Cysts proximate, epicavate, overall shape somewhat conical with an elongate anterior part; periphragm smooth or ornamented with features of low relief; archaeopyle types I, 2I or 3I.
Description:
Shape: Somewhat conical with an elongate anterior epicyst; hypocyst may be lobate posteriorly.
Wall relationships: Cysts epicavate, epicoel prominent; endocyst occupies nearly all of the hypocyst.
Wall features: No parasutural features; periphragm smooth or with features of low relief; endophragm smooth.
Archaeopyle: Type I, 2I or 3I; operculum typically detached, composed of 1 to 3 elongate anterior intercalary paraplates.
Paratabulation: Indicated by archaeopyle only.
Paracingulum: Not indicated.
Parasulcus: Not indicated.
Size: Small to intermediate, length about 40-65 µm
Affinities:
Phallocysta differs from Pareodinia Deflandre 1947 emended Stover and Evitt 1978 in being cavate.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Riding 1994, p. 13:
Remarks/Affinities:
The emendations of both Riding (1984) and Below (1987) are cited here. Riding (1984) stressed the consistently epicavate nature of this genus and described the subspherical, antapically-positioned endocyst. These features were not mentioned in the later emendation by Below (1987), which focused principally on the paratabulation.
Junior Synonym. Andreedinium Below 1987.
The genus Andreedinium Below 1987 differs only from Phallocysta in having adnate, as opposed to free, opercular pieces; these genera have identical shapes, sizes, cyst organizations, paratabulations, archeopyle paraplate equivalence, ornamentation and stratigraphic distributions. The anterior intercalary paraplates of Andreedinium arcticum Below 1987 (the type species) are adnate posteriorly to the precingular series. In the view of the author, this relatively minor difference does not warrant the retention of two otherwise identical genera, especially when preservation dictates that the distinction is frequently difficult to discern using the transmitted light microscope. Thus Andreedinium is herein deemed to be a junior synonym of Phallocysta. This means that the archeopyle type of Phallocysta is anterior intercalary, the compound opercular pieces are adnate posteriorly or free (type 3Ia or 3I).
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Phallocysta Dörhöfer and Davies, 1980, emend. Riding, 1984b, emend. Below, 1987a. Below (1987a, p.132) emended the diagnosis as follows. Arrangement of plates on the dinoflagellate amphiesma cop, pop, cap, 5`, 3a, 7"-6", 7c, 5"' , 2"' , as, y, z, ps; 1"' and 2"' located symmetrically on either side of the dorsoventral plane. Cyst habit proximate, proximochorate, chorate, acavate-cavate, sio or oblong spheroidal, ovoidal, avaloida, peridinioidal, equatorial cross section lenticular, reniform, oval, circular, with or without polar processes, size variable; wall composed of pedium, also with luxuria; surface smooth, ornamented, nonareate, areate, areae marked by finate ornament, limbi, or intraareate ornamentation; archeopyle anterior intercalary 1a + 2a + 3a; operculum triareate, solvate, opercular pieces secate, general opercular formula 1a + 2a +3a. According to Feist-Burkhardt 1994), this genus has a type 3I archeopyle with an adnate operculum.