Back
Tubotuberella
From Williams et al., 2017:
[Tubotuberella, Vozzhennikova, 1967, p.179–180; Emendations: Brideaux, 1977, p. 36; Sarjeant, 1982b, p. 41; Dodekova, 1990, p. 32-33.
Type species: Tubotuberella rhombiformis, Vozzhennikova, 1967 (pl.101, figs.2a–b; pl.104, fig.2) (which see for lectotype).]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Vozzhennikova, 1967]: (Translation: Lees in Sarjeant (Ed.), 1971):
Diagnosis:
Theca elongate along longitudinal axis with strongly convex lateral sides due to ellipsoidal and egg-shaped inner body. Latter is located in middle region or somewhat nearer the apical end of the theca. Epitheca slightly smaller or almost the same size as the hypotheca, conical, semisphaerical, with small, sometimes elongate apical projection. Hypotheca gradually or sharply tapered, tubular antapical part terminates in square or round aperture. Transverse furrow equatorial, shallow, circular, its ends far removed from one another. Longitudinal furrow has the form of a wide ventral field, bounded by costae which extend from the ends of the transverse furrow to the poles. Shell thin, smooth or sculptured, divided into fields by linear smooth or serrate costae. Shell of inner body thick, smooth, transparent, light-yellow. Pylome rounded trapezoidal, occupying a position corresponding to the third pre-equatorial plate. Boundaries of archeopyle indistinct.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended descriptions:
Brideaux, 1977:
Diagnosis:
Shape: Pericyst ambitus elongate; the epipericyst tapering but not prolonged into an apical prominence or horn; the hypopericyst tapering sharply and then more gently, the posterior part in the shape of an inverted frustum, quadrate or tubular in cross-section, and open at the antapex, forming an antapical breach.
Endocyst ambitus slightly elongated, ovoid to rounded sub-rhombic; not produced to form an apical prominence. Apical and antapical pericoel developed by separation of the pericyst and endocyst in the regions of the anterior epipericyst and posterior hypopericyst respectively. Ambital pericoel not developed; compression dorso-ventral.
Phragma: Periphragm smooth, of constant thickness and raised into low, narrow parasutural ridges; parasutures smooth or variably ornamented.
Endophragm smooth.
Paratabulation: Paratabulation determined from published figures as ?4`, 6``, 0c, 5```-?6```, 1```` (antapical breach present).
Archeopyle/operculum: Periarcheopyle formed by the loss of the third precingular paraplate; perioperculum simple, detached. Endoarcheopyle and endoperculum presumably similar but not observed.
Pericingulum/perisulcus: Pericingulum denoted by low, smooth or ornamented parasutures, slightly helicoidal; cingular paratabulation present or absent. Perisulcus present wide anteriorly, the anterior termination commonly poorly delimited; narrowing posteriorly, terminating adjacent to the antapical breach; laterally delimited by low parasutural ridges; perisulcus slightly depressed relative to the rest of the pericyst outline.
Affinities:
Tubotuberella Vozzhennikova differs from Glabridinium in the possession of paratabulation and lack of an apical horn, from Psaligonyaulax in the lack of an apical horn, from Dimidiadinium in the possession of a distinct apical pericoel and lack of an apical horn, and from Hystrichosphaeropsis, Rottnestia and Triblastula in the shape of the hypopericyst. Individual species of these latter three genera also lack an antapical breach and may possess an apical horn.
---------------------------------------
Sarjeant, 1982:
Diagnosis:
Proximate dinoflagellate cysts, broadly ellipsoidal to elongate ellipsoidal in ambitus, with apex acute and antapex truncate. Bicavate, with epipericoel and hypopericoel of variable relative proportions and with hypopericoel diverging from the anterior part of the hypotract at a marked angle. Endoblast subspherical to ovoidal, with or without a slight apical prominence. Parasutures feebly to clearly marked by lines or low ridges on the periblast, sometimes giving rise to very short, widely spaced spinelets; crests not developed, gonal spinules lacking.
Paratabulation 0-?2pa, 3-4`, ?-a, 6``, 0-6c, 5-6```, 1p, 0-1pv, 1````. Paraplate 4` is elongate, almost as long as 1` and having only a short boundary with 6``; the latter paraplate varies in shape from almost quadrate to triangular, with convex, straight or concave sides. The boundary between 4` and 6`` intersects the right lateral boundary of 1` in a position somewhat, or markedly, anterior to the junction of the latter paraplate with the sulcus. Antapex of periblast penetrated, or entirely occupied, by an opisthopyle. Surface of endoblast and periblast typically smooth or only lightly ornamented by granules or punctae.
Archaeopyle single-plate precingular, formed by loss of paraplate 3``; operculum reduced.
Affinities:
Tubotuberella is distinguished from Gonyaulacysta by its virtual lack of parasutural ornament and its greater degree of hypotractal cavation, and from Hystrichosphaeropsis in particularly by the form of its pericoels.
---------------------------------------
Dodekova, 1990:
Diagnosis:
The same as Sarjeant`s (1982, p. 41) with the following addition: a characteristic morphological feature in the species of the genus Tubotuberella is the ever strongly inclined, ventrally Iying antapical plate 1````, which is at 30° angle with the dorsal postcingular plate 4```. Introduced here is the term "inclination", from the Latin word -inclino- to incline, for expressing the inclination of the antapical plate. The opistopyle is positioned on the lower end of the antapical plate 1````, on the boundary with the postcingular plate 4``` and is never occupying the whole antapical plate. Tabulation formula: 0-2?pr,.4`, a?, 6", 6c, 6```, 1p, 1pv, 1````, s?.
Affinities:
The generic diagnosis is here made more precise by the tabulation formula for the more distinctly tabulated species, the tabulation of the hypocyst (fig. 4) and the structure of the hypopericoel. The latter was firstly illustrated by Gocht (1970, p 143, figs 12, 15). The development of opistopyles is due to the availability of hypopericoel and ventrally inclined antapical plate. The latter is poorly pronounced in G. jurassica where the antapical plate is sometimes slightly inclined. In G. eisenackii the inclination of 1```` is greater and the opistopyles respectively are of larger size. The inclination angle in G. eisenackii is bigger than that in the species of the genus Tubotuberella. On the grounds of the above, bearing in mind the untypical inclination and other features of G. eisenackii designated by Sarjeant (1982, pp. 19-25), I preserve the species to be referred to the genus Conyaulacysta.
In the case of large opistopyles, a secondary increase of the inclination angle may sometimes occur. In such case much more measurements of different specimens should be made.
For the greater part of the species belonging to the genus Tubotuberrella the inclination is about 20¦ (T. rkombiformis, T. .sphaerocepkalus, T. dangeardii, T. egementii, T. whatleyi) and about 25¦ (T. uncinata). The measurements have been made using the microphotographs on the holotypes published. In my believe the illustrated tabulation schemes of T. dangeardii subsp. dangeradii Sarjeant (1968, p. 226, fig. 3 and 1982, p. 22, fig. 5c, d) and T. egefftentii Gitmez (1970, p. 273, fig. 18) do not reflect the real tabulation. The opistopyle is considered tobe antapical plate, and the markedly inclined plate 1```` may be seen on the photographs of Sarjeant (1968, pl.1, fig.21; pl. 3,figs8, 15; 1982a, pl. 5, fig. 7; pl. 8, figs 4, 6) and Gitmez (1970, pl. 10, fig. 5). The correct tabulation scheme is shown on fig. 4 where the inclination is very typical. The strongly inclined antapical plate is causing deformation on the postcingular plates 3``` and 5```. The latter ones have short ventral and highly elongated lateraldorsal sides. The dorsal part of the hypocyst is occupied by an extendedly-trapezoid plate 4".
The inclination in T. dentata Raynaud, 1978 was not measured because on all microphotograplls (Raynaud, 1978, pl. 2, fig. 13 and Jan Du Chene et al., 1986 pl. 126, figs 1-3) the sutures are blurred by broad sutural crests and the tabulation, and the position of plate 1```` is dubious. I suppose that the inclination is over 30¦ and taking into account also the presence of caudiculae, and the general view of the cyst, I am coming to the conclusion that T. dentata Raynaud, 1978, p. 395, pl. 2, fig. 13 is to be referred to the genus Gonyaulacysta dentata (Raynaud, 1978), analogically to G. eiseflackii.
Another species having inclination analogical to the one characteristic for the genus Tubotuberella is Scriniodinium asymmetricum (Riding, 1987), though a number of other morphological features keep it to be belonging to the genus Scriniodinium.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:
Stover and Evitt 1978, p. 197-198:
Synopsis:
Cysts proximate, bicavate, elongate ellipsoidal, with or without an apical horn; hypocyst has prominent four-sided pericoel with porelike opening; endocyst subspherical to ovoidal; paratabulation gonyaulacacean, indicated by smooth to denticulate parasutural ridges or septa; archeopyle precingular, Type P.
Description:
Shape: Elongate ellipsoidal, with or without an apical horn, and with a subcylindrical, distally open antapical part.
Wall relationships: Cysts bicavate; hypocyst has characteristically prominent, elongate, four sided pericoel, and hypoperiphragm has a distal porelike opening at the posterior end of paraplate 1````.
Wall features: Parasutural ridges or septa with smooth to denticulate crests; parasutural features may be faint or absent; periphragm and endophragm smooth or faintly ornamented.
Paratabulation: Indicated generally by parasutural ridges or septa; gonyaulacacean, formula: 3-4`, 6``, X or 5?c, 5-6```, 0-1p, 1````; complete paratabulation rarely expressed, and may be lacking altogether on some specimens.
Archeopyle: Precingular, Type P (3`` only); operculum free.
Paracingulum: Generally indicated by parallel, transverse, parasutural ridges or septa.
Parasulcus: Expressed as longitudinal elongate area between parasutural ridges.
Size: Intermediate to large.
Affinities:
Tubotuberella differs from Psaligonyaulax in having a more narrow, elongate hypoperiphragm, which has a conspicuous antapical hole in the dorsal part of paraplate 1````. In addition, the longitudinal ridges delimiting paraplate 4``` commonly extend beyond the margin of the antapical hole. Psaligonyaulax lacks the antapical hole and has a wider antapical pericoel.
[Tubotuberella, Vozzhennikova, 1967, p.179–180; Emendations: Brideaux, 1977, p. 36; Sarjeant, 1982b, p. 41; Dodekova, 1990, p. 32-33.
Type species: Tubotuberella rhombiformis, Vozzhennikova, 1967 (pl.101, figs.2a–b; pl.104, fig.2) (which see for lectotype).]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Vozzhennikova, 1967]: (Translation: Lees in Sarjeant (Ed.), 1971):
Diagnosis:
Theca elongate along longitudinal axis with strongly convex lateral sides due to ellipsoidal and egg-shaped inner body. Latter is located in middle region or somewhat nearer the apical end of the theca. Epitheca slightly smaller or almost the same size as the hypotheca, conical, semisphaerical, with small, sometimes elongate apical projection. Hypotheca gradually or sharply tapered, tubular antapical part terminates in square or round aperture. Transverse furrow equatorial, shallow, circular, its ends far removed from one another. Longitudinal furrow has the form of a wide ventral field, bounded by costae which extend from the ends of the transverse furrow to the poles. Shell thin, smooth or sculptured, divided into fields by linear smooth or serrate costae. Shell of inner body thick, smooth, transparent, light-yellow. Pylome rounded trapezoidal, occupying a position corresponding to the third pre-equatorial plate. Boundaries of archeopyle indistinct.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended descriptions:
Brideaux, 1977:
Diagnosis:
Shape: Pericyst ambitus elongate; the epipericyst tapering but not prolonged into an apical prominence or horn; the hypopericyst tapering sharply and then more gently, the posterior part in the shape of an inverted frustum, quadrate or tubular in cross-section, and open at the antapex, forming an antapical breach.
Endocyst ambitus slightly elongated, ovoid to rounded sub-rhombic; not produced to form an apical prominence. Apical and antapical pericoel developed by separation of the pericyst and endocyst in the regions of the anterior epipericyst and posterior hypopericyst respectively. Ambital pericoel not developed; compression dorso-ventral.
Phragma: Periphragm smooth, of constant thickness and raised into low, narrow parasutural ridges; parasutures smooth or variably ornamented.
Endophragm smooth.
Paratabulation: Paratabulation determined from published figures as ?4`, 6``, 0c, 5```-?6```, 1```` (antapical breach present).
Archeopyle/operculum: Periarcheopyle formed by the loss of the third precingular paraplate; perioperculum simple, detached. Endoarcheopyle and endoperculum presumably similar but not observed.
Pericingulum/perisulcus: Pericingulum denoted by low, smooth or ornamented parasutures, slightly helicoidal; cingular paratabulation present or absent. Perisulcus present wide anteriorly, the anterior termination commonly poorly delimited; narrowing posteriorly, terminating adjacent to the antapical breach; laterally delimited by low parasutural ridges; perisulcus slightly depressed relative to the rest of the pericyst outline.
Affinities:
Tubotuberella Vozzhennikova differs from Glabridinium in the possession of paratabulation and lack of an apical horn, from Psaligonyaulax in the lack of an apical horn, from Dimidiadinium in the possession of a distinct apical pericoel and lack of an apical horn, and from Hystrichosphaeropsis, Rottnestia and Triblastula in the shape of the hypopericyst. Individual species of these latter three genera also lack an antapical breach and may possess an apical horn.
---------------------------------------
Sarjeant, 1982:
Diagnosis:
Proximate dinoflagellate cysts, broadly ellipsoidal to elongate ellipsoidal in ambitus, with apex acute and antapex truncate. Bicavate, with epipericoel and hypopericoel of variable relative proportions and with hypopericoel diverging from the anterior part of the hypotract at a marked angle. Endoblast subspherical to ovoidal, with or without a slight apical prominence. Parasutures feebly to clearly marked by lines or low ridges on the periblast, sometimes giving rise to very short, widely spaced spinelets; crests not developed, gonal spinules lacking.
Paratabulation 0-?2pa, 3-4`, ?-a, 6``, 0-6c, 5-6```, 1p, 0-1pv, 1````. Paraplate 4` is elongate, almost as long as 1` and having only a short boundary with 6``; the latter paraplate varies in shape from almost quadrate to triangular, with convex, straight or concave sides. The boundary between 4` and 6`` intersects the right lateral boundary of 1` in a position somewhat, or markedly, anterior to the junction of the latter paraplate with the sulcus. Antapex of periblast penetrated, or entirely occupied, by an opisthopyle. Surface of endoblast and periblast typically smooth or only lightly ornamented by granules or punctae.
Archaeopyle single-plate precingular, formed by loss of paraplate 3``; operculum reduced.
Affinities:
Tubotuberella is distinguished from Gonyaulacysta by its virtual lack of parasutural ornament and its greater degree of hypotractal cavation, and from Hystrichosphaeropsis in particularly by the form of its pericoels.
---------------------------------------
Dodekova, 1990:
Diagnosis:
The same as Sarjeant`s (1982, p. 41) with the following addition: a characteristic morphological feature in the species of the genus Tubotuberella is the ever strongly inclined, ventrally Iying antapical plate 1````, which is at 30° angle with the dorsal postcingular plate 4```. Introduced here is the term "inclination", from the Latin word -inclino- to incline, for expressing the inclination of the antapical plate. The opistopyle is positioned on the lower end of the antapical plate 1````, on the boundary with the postcingular plate 4``` and is never occupying the whole antapical plate. Tabulation formula: 0-2?pr,.4`, a?, 6", 6c, 6```, 1p, 1pv, 1````, s?.
Affinities:
The generic diagnosis is here made more precise by the tabulation formula for the more distinctly tabulated species, the tabulation of the hypocyst (fig. 4) and the structure of the hypopericoel. The latter was firstly illustrated by Gocht (1970, p 143, figs 12, 15). The development of opistopyles is due to the availability of hypopericoel and ventrally inclined antapical plate. The latter is poorly pronounced in G. jurassica where the antapical plate is sometimes slightly inclined. In G. eisenackii the inclination of 1```` is greater and the opistopyles respectively are of larger size. The inclination angle in G. eisenackii is bigger than that in the species of the genus Tubotuberella. On the grounds of the above, bearing in mind the untypical inclination and other features of G. eisenackii designated by Sarjeant (1982, pp. 19-25), I preserve the species to be referred to the genus Conyaulacysta.
In the case of large opistopyles, a secondary increase of the inclination angle may sometimes occur. In such case much more measurements of different specimens should be made.
For the greater part of the species belonging to the genus Tubotuberrella the inclination is about 20¦ (T. rkombiformis, T. .sphaerocepkalus, T. dangeardii, T. egementii, T. whatleyi) and about 25¦ (T. uncinata). The measurements have been made using the microphotographs on the holotypes published. In my believe the illustrated tabulation schemes of T. dangeardii subsp. dangeradii Sarjeant (1968, p. 226, fig. 3 and 1982, p. 22, fig. 5c, d) and T. egefftentii Gitmez (1970, p. 273, fig. 18) do not reflect the real tabulation. The opistopyle is considered tobe antapical plate, and the markedly inclined plate 1```` may be seen on the photographs of Sarjeant (1968, pl.1, fig.21; pl. 3,figs8, 15; 1982a, pl. 5, fig. 7; pl. 8, figs 4, 6) and Gitmez (1970, pl. 10, fig. 5). The correct tabulation scheme is shown on fig. 4 where the inclination is very typical. The strongly inclined antapical plate is causing deformation on the postcingular plates 3``` and 5```. The latter ones have short ventral and highly elongated lateraldorsal sides. The dorsal part of the hypocyst is occupied by an extendedly-trapezoid plate 4".
The inclination in T. dentata Raynaud, 1978 was not measured because on all microphotograplls (Raynaud, 1978, pl. 2, fig. 13 and Jan Du Chene et al., 1986 pl. 126, figs 1-3) the sutures are blurred by broad sutural crests and the tabulation, and the position of plate 1```` is dubious. I suppose that the inclination is over 30¦ and taking into account also the presence of caudiculae, and the general view of the cyst, I am coming to the conclusion that T. dentata Raynaud, 1978, p. 395, pl. 2, fig. 13 is to be referred to the genus Gonyaulacysta dentata (Raynaud, 1978), analogically to G. eiseflackii.
Another species having inclination analogical to the one characteristic for the genus Tubotuberella is Scriniodinium asymmetricum (Riding, 1987), though a number of other morphological features keep it to be belonging to the genus Scriniodinium.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:
Stover and Evitt 1978, p. 197-198:
Synopsis:
Cysts proximate, bicavate, elongate ellipsoidal, with or without an apical horn; hypocyst has prominent four-sided pericoel with porelike opening; endocyst subspherical to ovoidal; paratabulation gonyaulacacean, indicated by smooth to denticulate parasutural ridges or septa; archeopyle precingular, Type P.
Description:
Shape: Elongate ellipsoidal, with or without an apical horn, and with a subcylindrical, distally open antapical part.
Wall relationships: Cysts bicavate; hypocyst has characteristically prominent, elongate, four sided pericoel, and hypoperiphragm has a distal porelike opening at the posterior end of paraplate 1````.
Wall features: Parasutural ridges or septa with smooth to denticulate crests; parasutural features may be faint or absent; periphragm and endophragm smooth or faintly ornamented.
Paratabulation: Indicated generally by parasutural ridges or septa; gonyaulacacean, formula: 3-4`, 6``, X or 5?c, 5-6```, 0-1p, 1````; complete paratabulation rarely expressed, and may be lacking altogether on some specimens.
Archeopyle: Precingular, Type P (3`` only); operculum free.
Paracingulum: Generally indicated by parallel, transverse, parasutural ridges or septa.
Parasulcus: Expressed as longitudinal elongate area between parasutural ridges.
Size: Intermediate to large.
Affinities:
Tubotuberella differs from Psaligonyaulax in having a more narrow, elongate hypoperiphragm, which has a conspicuous antapical hole in the dorsal part of paraplate 1````. In addition, the longitudinal ridges delimiting paraplate 4``` commonly extend beyond the margin of the antapical hole. Psaligonyaulax lacks the antapical hole and has a wider antapical pericoel.