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Imbatodinium kondratjevii
Imbatodinium kondratjevii Vozzhennikova, 1967; emend. D÷rh÷fer and Davies, 1980 ; emend. Lentin and Vozzhennikova, 1990
Originally (and now) Imbatodinium, subsequently Pareodinia.
Wiggins, 1975, transferred this species to Pareodinia Deflandre, 1947. Dörhöfer and Davies, 1980, retained it in Imbatodinium.
Below, 1990, provided an emended description for this species without examining the holotype and retained it in Pareodinia, thus agreeing with Wiggins, 1975, in treating Imbatodinium as a tax. jr. synonym of Pareodinia Deflandre, 1947. In the same publication, Below, 1990, listed Imbatodinium in synonymy with Necrobroomea Wiggins, 1975.
Lentin and Williams, 1993, followed Harker and Sarjeant, 1991, and retained Imbatodinium as a separate genus, and followed Lentin and Vozzhennikova, 1990, who retained the species as Imbatodinium kondratjevii and provided an emended diagnosis after re-examination of the holotype.
Holotype: Vozzhennikova, 1967, pl.9, figs.4-5 pl.10, figs.1a-b; Lentin and Vozzhennikova, 1990, pl.11, figs.1-2, text-figs.48a-b
Locus typicus: W. Siberia (Verkne-Imbatskoi), Russia
Stratum typicum: Late Jurassic
Translation Vozzhennikova, 1967: Sarjeant (Ed.). 1971, p. 79-81
Original description: Vozzhennikova, 1967, p. 55
Theca attenuate, pyriform. Epitheca 2.5 - 3 times bigger than the hypotheca with a straight or slightly bent apical process, which is rounded at the distal end or bears a slender setiform outgrowth (plate VII, fig. 1) which is usually incompletely preserved. The hypotheca has two antapical processes, one of which is more broadly rounded and noticeably larger than the other. The latter is small and beak-like in appearance (plate X, fig. 1a). The transverse furrow is deep, annulate. The longitudinal furrow is shallow, S-shaped and onlu clearly discernible on rotating the specimen about its longitudinal axis. The theca is thick granular. The pylome has an oval outline and is situated a little below the apical process. Archeopyle apical.
Dimensions:
Type: length 108.0 µm, breadth 35.1 µm, length of epitheca 81.0 µm, length of hypotheca 27.0 µm, length of apical process 21.6 µm, width of apical process about 3 µm, width of transverse furrow 5.4 µm, pylome 10.8 x 16.2 µm.
Other specimens: length 81.0-108.0 µm, breadth 29.7-37.8 µm, length of epitheca 54-81 µm, length of hypotheca 21.6-27.0 µm, length of apical process 13.5-21.6 µm, width of apical, 2.7-5.4 µm, width of transverse furrow 5.4-10.8 µm, pylome 10.8x16.2 µm, 16.2x18.9 µm.
Emendation: Dörhöfer and Davies, 1980, p. 37
The species is emended to include reference to an (AI) archeopyle, probably involving four apical and two intercalary plates. In all other respects our specimens from the Sverdrup Basin conform with the original description.
The presence of two anterior intercalary plates could be established under the interference ontrast microscope; however, all sutures are very faint and are not easily photographed. These sutures are not expressed by sculptural elements and are not normally visible with SEM, suggesting that they constitute differentiations within the phragme or are expressed on its inner surface. One aberrant specimen displayed 2I achaeopyle. The ornament is corrugated-granular. A mid-ventral internal thickening (omphalos) is ususally present (as in all pseudoceratiaceans studied) (Fig. 30B). The left antapical horn is generally longer. The cingulum is not always as well pronounced as the original description suggets.
Affinities:
Vozzhennikova, 1967, p. 55
This species differs from other members of the genus in having a sculptured envelope and less convex sides.
Poulsen 1996 p. 61-62 Pl. 5, Figs. 12-13: Imbatodinium kondratjevii Vozzhennikova 1967 emend. Lentin & Vozzhennikova 1990
Remarks. The emendation of this species and the genus by Lentin and Vozzhennikova (1990) state the archeopyle is unidenilate, type 2I (i.e. an eleven sided archeopyle opening created by a six sided paraplate and a seven sided paraplate, Lentin and Vozzhennikova, 1990, p. 87). See P. robusta for further discussion. The Polish specimens of I. kondraljevii are within the lower part of the size range in length (81-108 Ám) as described by Vozzhennikova (1967; 1971).
Originally (and now) Imbatodinium, subsequently Pareodinia.
Wiggins, 1975, transferred this species to Pareodinia Deflandre, 1947. Dörhöfer and Davies, 1980, retained it in Imbatodinium.
Below, 1990, provided an emended description for this species without examining the holotype and retained it in Pareodinia, thus agreeing with Wiggins, 1975, in treating Imbatodinium as a tax. jr. synonym of Pareodinia Deflandre, 1947. In the same publication, Below, 1990, listed Imbatodinium in synonymy with Necrobroomea Wiggins, 1975.
Lentin and Williams, 1993, followed Harker and Sarjeant, 1991, and retained Imbatodinium as a separate genus, and followed Lentin and Vozzhennikova, 1990, who retained the species as Imbatodinium kondratjevii and provided an emended diagnosis after re-examination of the holotype.
Holotype: Vozzhennikova, 1967, pl.9, figs.4-5 pl.10, figs.1a-b; Lentin and Vozzhennikova, 1990, pl.11, figs.1-2, text-figs.48a-b
Locus typicus: W. Siberia (Verkne-Imbatskoi), Russia
Stratum typicum: Late Jurassic
Translation Vozzhennikova, 1967: Sarjeant (Ed.). 1971, p. 79-81
Original description: Vozzhennikova, 1967, p. 55
Theca attenuate, pyriform. Epitheca 2.5 - 3 times bigger than the hypotheca with a straight or slightly bent apical process, which is rounded at the distal end or bears a slender setiform outgrowth (plate VII, fig. 1) which is usually incompletely preserved. The hypotheca has two antapical processes, one of which is more broadly rounded and noticeably larger than the other. The latter is small and beak-like in appearance (plate X, fig. 1a). The transverse furrow is deep, annulate. The longitudinal furrow is shallow, S-shaped and onlu clearly discernible on rotating the specimen about its longitudinal axis. The theca is thick granular. The pylome has an oval outline and is situated a little below the apical process. Archeopyle apical.
Dimensions:
Type: length 108.0 µm, breadth 35.1 µm, length of epitheca 81.0 µm, length of hypotheca 27.0 µm, length of apical process 21.6 µm, width of apical process about 3 µm, width of transverse furrow 5.4 µm, pylome 10.8 x 16.2 µm.
Other specimens: length 81.0-108.0 µm, breadth 29.7-37.8 µm, length of epitheca 54-81 µm, length of hypotheca 21.6-27.0 µm, length of apical process 13.5-21.6 µm, width of apical, 2.7-5.4 µm, width of transverse furrow 5.4-10.8 µm, pylome 10.8x16.2 µm, 16.2x18.9 µm.
Emendation: Dörhöfer and Davies, 1980, p. 37
The species is emended to include reference to an (AI) archeopyle, probably involving four apical and two intercalary plates. In all other respects our specimens from the Sverdrup Basin conform with the original description.
The presence of two anterior intercalary plates could be established under the interference ontrast microscope; however, all sutures are very faint and are not easily photographed. These sutures are not expressed by sculptural elements and are not normally visible with SEM, suggesting that they constitute differentiations within the phragme or are expressed on its inner surface. One aberrant specimen displayed 2I achaeopyle. The ornament is corrugated-granular. A mid-ventral internal thickening (omphalos) is ususally present (as in all pseudoceratiaceans studied) (Fig. 30B). The left antapical horn is generally longer. The cingulum is not always as well pronounced as the original description suggets.
Affinities:
Vozzhennikova, 1967, p. 55
This species differs from other members of the genus in having a sculptured envelope and less convex sides.
Poulsen 1996 p. 61-62 Pl. 5, Figs. 12-13: Imbatodinium kondratjevii Vozzhennikova 1967 emend. Lentin & Vozzhennikova 1990
Remarks. The emendation of this species and the genus by Lentin and Vozzhennikova (1990) state the archeopyle is unidenilate, type 2I (i.e. an eleven sided archeopyle opening created by a six sided paraplate and a seven sided paraplate, Lentin and Vozzhennikova, 1990, p. 87). See P. robusta for further discussion. The Polish specimens of I. kondraljevii are within the lower part of the size range in length (81-108 Ám) as described by Vozzhennikova (1967; 1971).