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Trichodinium rhomboidale
From Fensome et al., 2019:
Trichodinium? rhomboidale Górka, 1965, p.301–302, pl.1, figs.6a–b ex Sarjeant, 1967b, p.255–256.
Holotype: Górka, 1965, pl.1, figs.6a–b; Jan du Chêne et al., 1986a, pl.121, figs.14–15.
Originally Palaeoperidinium (name not validly published), subsequently (and now) Trichodinium?.
Questionable assignment: Sarjeant (1967b, p.256). The name Palaeoperidinium rhomboidale was not validly published in Górka (1965) since the generic name Palaeoperidinium was not validly published until 1967.
Williams et al. (1998, p.616) accepted Sarjeant's (1967b) indirect reference to Górka (1965) as indication of a type (ICN Article 40.3).
Lentin and Williams (1976, p.111) also proposed this name, as a new combination.
Age: early Kimmeridgian.
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Original description (Górka, 1965) translation: PKB 2024
Holotypus: slide AY 1.
Stratum typicum: Kimmeridgian.
Locus typicus: Magnuszew, prof. 1219,4 m.
Derivatio nominis: rhomboidalis - rhomboidal form
Dimensions (in µm): (slide AY 1)
Theca length without process 45.24
Library width without process 40.00
Width of transverse furrow 1.74
Epithecal length 17.40
Mortgage length 26.10
Length of forked processes 2.00-8.70
Length of straight processes 1.70-3.48
Description. - Quadrilateral theca with rounded corners, divided by a narrow transverse furrow into epitheca and hypotheca, the latter a little larger. Absence of longitudinal furrow, apical horn and tabulation. At the periphery of the mortgage there are processes quite close to each other. Their ends fork clearly in the plane perpendicular to the main axis and are often linked between them. Their size decreases towards the transverse furrow. At the periphery of the epitheca processes of this type are rare. On the other hand, this is covered with short and straight processes which are also found on the surface of the entire theca. The surface of the theca finely reticulated. Remarks. - Palaeoperidinium rhomboidalis n.sp. by its close rhomboid shape, resembles the genus Spongodinium DefI. (Deflandre, 1936, p. 21-22), but it differs by the absence of archaeopyle, of apical horn, by the more rounded angles of the theca and by the structure of the surface which in Spongodinium is alveolate. Although Professor G. Deflandre suggested to me (in litt.) to place this form in the genus Spongodinium by completing the diagnosis of the latter, it nevertheless seems to me that given the differences mentioned above and the presence of a single copy, it is preferable to classify it in the genus Palaeoperidinium DefI. Distribution. ..:.- Magnuszew Kimmeridgian (depth 1219.4 m).
Trichodinium? rhomboidale Górka, 1965, p.301–302, pl.1, figs.6a–b ex Sarjeant, 1967b, p.255–256.
Holotype: Górka, 1965, pl.1, figs.6a–b; Jan du Chêne et al., 1986a, pl.121, figs.14–15.
Originally Palaeoperidinium (name not validly published), subsequently (and now) Trichodinium?.
Questionable assignment: Sarjeant (1967b, p.256). The name Palaeoperidinium rhomboidale was not validly published in Górka (1965) since the generic name Palaeoperidinium was not validly published until 1967.
Williams et al. (1998, p.616) accepted Sarjeant's (1967b) indirect reference to Górka (1965) as indication of a type (ICN Article 40.3).
Lentin and Williams (1976, p.111) also proposed this name, as a new combination.
Age: early Kimmeridgian.
---------------------------------------------------------------------------------------------------
Original description (Górka, 1965) translation: PKB 2024
Holotypus: slide AY 1.
Stratum typicum: Kimmeridgian.
Locus typicus: Magnuszew, prof. 1219,4 m.
Derivatio nominis: rhomboidalis - rhomboidal form
Dimensions (in µm): (slide AY 1)
Theca length without process 45.24
Library width without process 40.00
Width of transverse furrow 1.74
Epithecal length 17.40
Mortgage length 26.10
Length of forked processes 2.00-8.70
Length of straight processes 1.70-3.48
Description. - Quadrilateral theca with rounded corners, divided by a narrow transverse furrow into epitheca and hypotheca, the latter a little larger. Absence of longitudinal furrow, apical horn and tabulation. At the periphery of the mortgage there are processes quite close to each other. Their ends fork clearly in the plane perpendicular to the main axis and are often linked between them. Their size decreases towards the transverse furrow. At the periphery of the epitheca processes of this type are rare. On the other hand, this is covered with short and straight processes which are also found on the surface of the entire theca. The surface of the theca finely reticulated. Remarks. - Palaeoperidinium rhomboidalis n.sp. by its close rhomboid shape, resembles the genus Spongodinium DefI. (Deflandre, 1936, p. 21-22), but it differs by the absence of archaeopyle, of apical horn, by the more rounded angles of the theca and by the structure of the surface which in Spongodinium is alveolate. Although Professor G. Deflandre suggested to me (in litt.) to place this form in the genus Spongodinium by completing the diagnosis of the latter, it nevertheless seems to me that given the differences mentioned above and the presence of a single copy, it is preferable to classify it in the genus Palaeoperidinium DefI. Distribution. ..:.- Magnuszew Kimmeridgian (depth 1219.4 m).