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Deflandrea
From Williams et al., 2017:
[Deflandrea, Eisenack, 1938b, p.187; Emendations: Williams and Downie, 1966c, p.231; Stover, 1974, p.169–170, as a revised description; Lentin and Williams, 1976, p.35–36.
tax. sr. synonym of:
Ceratiopsis Vozzhennikova, 1963, according to Lentin and Williams, 1976, Stover and Evitt, 1978, and Lindgren, 1984. Lentin and Williams, 1977, 1981, 1985, retained Ceratiopsis as a separate genus; Cerodinium Vozzhennikova, 1963, according to Lentin and Williams, 1976, Stover and Evitt, 1978, and Lindgren, 1984. Lentin and Williams, 1987, retained Cerodinium as a separate genus; Senegalinium Jain and Millepied, 1973, according to Herngreen, 1975. Lentin and Williams, 1977, retained Senegalinium as a separate genus.
Type species: Deflandrea phosphoritica, Eisenack, 1938b (text-fig.6)]
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Original description: [Eisenack, 1938]: (Translation: Stover and Evitt, 1978, p. 99):
Diagnosis:
Deflandrea phosphoritica is characterized by its rounded inner body in apical view, oval in cross section, provided with a transverse band within its flattened, characteristically three-pointed outer shell.
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Emended description:
Williams and Downie, 1966:
Description:
Cavate cysts with periphragm forming elongate pentagonal (also often somewhat rounded to rhomboidal) outer shell. Lateral walls usually convex. One apical and two antapical horns, more or less reduced. Tabulation, when decipherable, peridinoid. Periphragm smooth or granular. Cingulum circular, longitudinal furrow if observable restricted to hypotract. Inner capsule circular in outline; endophragm of variable thickness. Archeopyle intercalary.
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Lentin and Williams, 1976:
Description:
Shape of pericyst: Ambitus ovoidal to pentagonal, elongated in an antero- posterior direction. Pericyst prolonged into one apical and two, more or less equal, symmetrically placed antapical horns, the right antapical horn sometimes being slightly reduced. This is the typical peridinoid outline. Compression: dorso-ventral.
Shape of endocyst: Ambitus circular to ovoidal, may be occasionally elongate or peridinoid. May be in contact with pericyst in precingular, cingular and postcingular regions.
Shape of pericoels: An apical and an antapical pericoel invariably present. They may be united by an ambital pericoel.
Shape of the periphragm: Usually of a constant thickness. Surface laevigate, scabrate, granulate, minutely echinate or minutely rugulate.
Endophragm: Less than 1 µm to several microns and commonly of variable thickness. Surface rarely laevigate, frequently scabrate, granulate, verrucate or tuberculate; the ornamentation can be localized or uniformly distributed.
Paratabulation of the pericyst: The penetabular spines of D. spinulosa and the parasutures visible in D. phosphoritica, particularly under the SEM, denote a peridinoidal paratabulation of 4`, 3a, 7``, 5```, 2````. 1` is a broad rhomboidal paraplate reaching almost to the peri-cingulum; 2` and 4` are elongate antero-posteriorly and narrow; 3` is considerably shorter. Of the anterior intercalaries, 1a and 3a are of similar size and shape; 2a is considerably larger and is pseudoquadra to hexa. It is usually broader than paraplate 4``. Of the precingulars 2`` and 6`` are elongate five-sided; 3`` and 5`` are shorter, narrow and five-sides; 4`` is quadrate. Of the postcingulars, 3``` is broad pentagonal; 1```, 2```, 4``` and 5``` are approximately equal in size and essentially four-sided. The antapicals 1```` and 2```` are of equal size and possess the same shape. Pandasutural striae are visible on several specimens of D. phosphoritica under the SEM.
Pericingulum: Always present, commonly indented, planar or very slightly helicoidal and composed of an unknown number of paraplates. Parasutures commonly as raised ridges or borders with smooth or denticulate margins.
Perisulcus: When visible of restricted width on the posterior epipericyst, gradually widening on the hypopericyst and extending almost to the antapex. Sulcal paraplates and flagellar scar may be visible.
Endocyst: Paratabulation not observed.
Periarcheopyle: Broad hexa to pseudoquadra intercalary, resulting from the loss of the second anterior intercalary paraplate, 2a. When the outline of 2a appears quadra detailed examination often reveals greatly reduced H3 and H5 parasutures. Perioperculum free. Transverse periarcheopyle index is 0.51-0.86. Transverse periarcheopyle ratio is 1.02-6.25.
Endoarcheopyle: Broad hexa to pseudoquadra intercalary, resulting from the loss of the second anterior intercalary paraplate, 2a. Endoperculum usually free. Archeopyle formula: I/I (2a/2a).
Dimensions: Pericyst length, 46-210 µm, breadth, 34-158 µm. Endocyst length, 20-92 µm, breadth, 31-96 µm.
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Modified description:
Stover and Evitt 1978, p. 100:
Synopsis:
Cysts bicavate or circumcavate, rarely cornucavate; compressed peridinioid to subellipsoidal, with one prominent to weakly developed apical and two antapical horns; periphragm smooth or with subdued ornamentation typically clusters separated by pandasuturate areas; peridiniacean; hexa style paratabulation indicated by archeopyle only and combination of periphragmal features; archeopyle intercalary, Type I/I; periarcheopyle index > 0.5.
Description:
Shape: Typically compressed peridinioid, but varying, depending on sizes and shapes of apical and antapical horns.
Wall relationships: Cysts commonly bicavate or circumcavate, less commonly cornucavate.
Wall features: Parasutural features generally absent; faint parasutural lines of low ridges present on some species. Periphragm smooth or variously ornamented with characteristically subdued features arranged in penitabular rows or intratabular clusters, or both, and separated by smooth pandasuturate areas. Endophragm generally smooth, occasionally coarsely ornamented.
Paratabulation: Variously expressed; mode of expression generally fairly constant within a species. Indicated partly by archeopyle only (minimum), to completely by parasutural lines or ridges (maximum); most commonly expressed by subdued penitabular or intratabular features and pandasuturate areas. Peridiniacean, hexa style paratabulation, formula: 4`, 3a, 7``, Xc, 5```, 2````, 0-5s; on most species the paraplates of the precingular, postcingular, and intercalary (at least 2a) series are determinable.
Archeopyle: Intercalary, Type I/I (2a only); periarcheopyle index > 0.5; operculum free; perioperculum wide and commonly extending nearly to the lateral margins; endoperculum usually smaller and proportioned slightly differently from the perioperculum.
Paracingulum: Commonly indicated by smooth to faintly ornamented transverse parallel ridges or by a local concavity (or rarely a convexity); expressed most clearly at the lateral margins and occasionally traceable elsewhere; rarely subdivided.
Parasulcus: Generally indicated by the interruption of the paracingulum and extending antapically as a shallow depression; individual paraplates and flagellar scar may be discernible.
Size: Intermediate to large.
Affinities:
The wide intercalary archeopyle is diagnostic of Deflandrea and serves to separate the genus from genera of similar appearance; for example, genera with narrow intercalary archeopyles, such as Alterbia and Isabelidinium, as well as those genera processing the kind of intercalary archeopyle associated with the quadra style paratabulation, such as Wetzeliella.
[Deflandrea, Eisenack, 1938b, p.187; Emendations: Williams and Downie, 1966c, p.231; Stover, 1974, p.169–170, as a revised description; Lentin and Williams, 1976, p.35–36.
tax. sr. synonym of:
Ceratiopsis Vozzhennikova, 1963, according to Lentin and Williams, 1976, Stover and Evitt, 1978, and Lindgren, 1984. Lentin and Williams, 1977, 1981, 1985, retained Ceratiopsis as a separate genus; Cerodinium Vozzhennikova, 1963, according to Lentin and Williams, 1976, Stover and Evitt, 1978, and Lindgren, 1984. Lentin and Williams, 1987, retained Cerodinium as a separate genus; Senegalinium Jain and Millepied, 1973, according to Herngreen, 1975. Lentin and Williams, 1977, retained Senegalinium as a separate genus.
Type species: Deflandrea phosphoritica, Eisenack, 1938b (text-fig.6)]
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Original description: [Eisenack, 1938]: (Translation: Stover and Evitt, 1978, p. 99):
Diagnosis:
Deflandrea phosphoritica is characterized by its rounded inner body in apical view, oval in cross section, provided with a transverse band within its flattened, characteristically three-pointed outer shell.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended description:
Williams and Downie, 1966:
Description:
Cavate cysts with periphragm forming elongate pentagonal (also often somewhat rounded to rhomboidal) outer shell. Lateral walls usually convex. One apical and two antapical horns, more or less reduced. Tabulation, when decipherable, peridinoid. Periphragm smooth or granular. Cingulum circular, longitudinal furrow if observable restricted to hypotract. Inner capsule circular in outline; endophragm of variable thickness. Archeopyle intercalary.
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Lentin and Williams, 1976:
Description:
Shape of pericyst: Ambitus ovoidal to pentagonal, elongated in an antero- posterior direction. Pericyst prolonged into one apical and two, more or less equal, symmetrically placed antapical horns, the right antapical horn sometimes being slightly reduced. This is the typical peridinoid outline. Compression: dorso-ventral.
Shape of endocyst: Ambitus circular to ovoidal, may be occasionally elongate or peridinoid. May be in contact with pericyst in precingular, cingular and postcingular regions.
Shape of pericoels: An apical and an antapical pericoel invariably present. They may be united by an ambital pericoel.
Shape of the periphragm: Usually of a constant thickness. Surface laevigate, scabrate, granulate, minutely echinate or minutely rugulate.
Endophragm: Less than 1 µm to several microns and commonly of variable thickness. Surface rarely laevigate, frequently scabrate, granulate, verrucate or tuberculate; the ornamentation can be localized or uniformly distributed.
Paratabulation of the pericyst: The penetabular spines of D. spinulosa and the parasutures visible in D. phosphoritica, particularly under the SEM, denote a peridinoidal paratabulation of 4`, 3a, 7``, 5```, 2````. 1` is a broad rhomboidal paraplate reaching almost to the peri-cingulum; 2` and 4` are elongate antero-posteriorly and narrow; 3` is considerably shorter. Of the anterior intercalaries, 1a and 3a are of similar size and shape; 2a is considerably larger and is pseudoquadra to hexa. It is usually broader than paraplate 4``. Of the precingulars 2`` and 6`` are elongate five-sided; 3`` and 5`` are shorter, narrow and five-sides; 4`` is quadrate. Of the postcingulars, 3``` is broad pentagonal; 1```, 2```, 4``` and 5``` are approximately equal in size and essentially four-sided. The antapicals 1```` and 2```` are of equal size and possess the same shape. Pandasutural striae are visible on several specimens of D. phosphoritica under the SEM.
Pericingulum: Always present, commonly indented, planar or very slightly helicoidal and composed of an unknown number of paraplates. Parasutures commonly as raised ridges or borders with smooth or denticulate margins.
Perisulcus: When visible of restricted width on the posterior epipericyst, gradually widening on the hypopericyst and extending almost to the antapex. Sulcal paraplates and flagellar scar may be visible.
Endocyst: Paratabulation not observed.
Periarcheopyle: Broad hexa to pseudoquadra intercalary, resulting from the loss of the second anterior intercalary paraplate, 2a. When the outline of 2a appears quadra detailed examination often reveals greatly reduced H3 and H5 parasutures. Perioperculum free. Transverse periarcheopyle index is 0.51-0.86. Transverse periarcheopyle ratio is 1.02-6.25.
Endoarcheopyle: Broad hexa to pseudoquadra intercalary, resulting from the loss of the second anterior intercalary paraplate, 2a. Endoperculum usually free. Archeopyle formula: I/I (2a/2a).
Dimensions: Pericyst length, 46-210 µm, breadth, 34-158 µm. Endocyst length, 20-92 µm, breadth, 31-96 µm.
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Modified description:
Stover and Evitt 1978, p. 100:
Synopsis:
Cysts bicavate or circumcavate, rarely cornucavate; compressed peridinioid to subellipsoidal, with one prominent to weakly developed apical and two antapical horns; periphragm smooth or with subdued ornamentation typically clusters separated by pandasuturate areas; peridiniacean; hexa style paratabulation indicated by archeopyle only and combination of periphragmal features; archeopyle intercalary, Type I/I; periarcheopyle index > 0.5.
Description:
Shape: Typically compressed peridinioid, but varying, depending on sizes and shapes of apical and antapical horns.
Wall relationships: Cysts commonly bicavate or circumcavate, less commonly cornucavate.
Wall features: Parasutural features generally absent; faint parasutural lines of low ridges present on some species. Periphragm smooth or variously ornamented with characteristically subdued features arranged in penitabular rows or intratabular clusters, or both, and separated by smooth pandasuturate areas. Endophragm generally smooth, occasionally coarsely ornamented.
Paratabulation: Variously expressed; mode of expression generally fairly constant within a species. Indicated partly by archeopyle only (minimum), to completely by parasutural lines or ridges (maximum); most commonly expressed by subdued penitabular or intratabular features and pandasuturate areas. Peridiniacean, hexa style paratabulation, formula: 4`, 3a, 7``, Xc, 5```, 2````, 0-5s; on most species the paraplates of the precingular, postcingular, and intercalary (at least 2a) series are determinable.
Archeopyle: Intercalary, Type I/I (2a only); periarcheopyle index > 0.5; operculum free; perioperculum wide and commonly extending nearly to the lateral margins; endoperculum usually smaller and proportioned slightly differently from the perioperculum.
Paracingulum: Commonly indicated by smooth to faintly ornamented transverse parallel ridges or by a local concavity (or rarely a convexity); expressed most clearly at the lateral margins and occasionally traceable elsewhere; rarely subdivided.
Parasulcus: Generally indicated by the interruption of the paracingulum and extending antapically as a shallow depression; individual paraplates and flagellar scar may be discernible.
Size: Intermediate to large.
Affinities:
The wide intercalary archeopyle is diagnostic of Deflandrea and serves to separate the genus from genera of similar appearance; for example, genera with narrow intercalary archeopyles, such as Alterbia and Isabelidinium, as well as those genera processing the kind of intercalary archeopyle associated with the quadra style paratabulation, such as Wetzeliella.