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Amphorulacysta monteilii
From Fensome et al., 2019:
Amphorulacysta? monteilii, (Dodekova, 1994, p.18–19, pl.1, figs.6–11,13–14; pl.2, figs.6–10; text-figs.4a–b) Williams and Fensome, 2016, p.139.
Holotype: Dodekova, 1994, pl.1, figs.13–14.
Originally Amphorula? (generic name illegitimate), subsequently (and now) Amphorulacysta?
Questionable assignment: Williams and Fensome (2016, p.139).
Age: late Tithonian–Berriasian.
Locus typicus: outcrop Mahala Popska, vicinity of the town of Sevlievo, Central North Bulgaria
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Original description: [Dodekova 1994, p. 18-19]:
Diagnosis:
The cyst is subspherical proximochorate-septate. The tabulation is gonyaulacacean indicted by low penitabular septa which may be arcuate semi-elliptical, semicircular to rectangular or polygonal in outline. Adcingular septa always open toward.s the cingulum. The cingulum is expressed by 6 pairs low subconical processes.
The archeopyle is apical, with deep accessory sutures and a sulcal notch. The operculum is free.
Description:
Acavate cyst. The cyst wall is composed of two appressed layers except where penitabular septa are formed. The superficial sculpture of the wall is illdefined. It consists of irregularly spaced, granules, pits, fine reticulum or smooth.
The tabulation repeats the classical gonyaulacacean pattern (Fig. 4) with a formula: 1-2 pr?, 4", 6", 6c, 6"", 1p, 1""", 5s.
The penitabular projections proximally start with thick ridges, striated, with or without rare perforations, which pass in thin septa (fig. 3, pl. 2, fig. 10). Distally the septa are entire or with rare denticulations and sporadic perforations. Monteil (1990, p. 598, pl. 1, figs. 2-4) very well described the apex organisation. There are 1 or 2 preapical plates (pl. I, figs. 8, 10; Monteil, 1990 pl. I, figs. 4a, b). In the centre of some opercula have subconical thicker place or group of granules. The four apical plates are arcuate or angular. Their form and dimensions are evident on the photos (pl I, figs. 7-11). The apical septa are always open towards preapical area but in some opercula the basal ridges may be closed (pl. 1, fig;. 7, 8). A great number of free opercula exists in palynological slides. They are so characteristic of the species that may be used for its identification. The adcingular series of plates possess arcuate-angular semi-elliptical, trapezoidal or semicircular septa, always open towards the cingulum. The septa of 1"", 6", 2"" and 6"" are relatively smaller than the others. The plate 1"" is the smallest, elliptic-angular with clear arcuate ridge septum towards the plate 2"", poorly, developed or absent towards the sulcus. The posterior plate -1p is polygonal with always closed septum. The single antapical plate 1"" is occupied by closed septum rounded six-sided or trapezoidal, asymmetric.
The cingulum is indicated by six pairs low subconical rectilinear processes, never with bifurcate tips. Their bases are not connected with the ridges as it is in the type species A. metaelliptica (pl. I, fig. 14; pl. 2, fig. 10). On rare occasions they may be connected with an allusion of ridges with the neighbour septa. It is often difficult to distinguish the cingular processes.
The sulcus (Fig. 4) is presented by low ridges with or without septa and includes: as- relatively large triangular open ridge; ras_small irregular-trapezoidal ridge; rs- and ls- clear, small arcuate ridges disposed opposite; pv (pr) - relatively large semi-elliptic open ridge with a low septum (pl. 2, fig. 7).
The morphological details of this species are observed on the well preserved specimens. The cysts are often broken or distorted to some extent, with secondary folds but the characteristic morphology permits their identification by the parts of the cyst. The intraspecific variability of the new species is expressed by insignificant variations of dimensions, the length of the septa varies in different specimens. The open ends of the ridges and septa in precingular and postcingular series normally are subparallel. But in some cysts the ends of neighbouring basal ridges converge one to other and rare are united. On another occasion the basal precingular ridges cross the cingulum and unit with the opposite postcingular ridges. Whether these instances are owing to the intraspecific variability or are provoked by deformation of the cyst is difficult to establish.
Dimensions (in µm):
Holotype: length without apex): 75, width: 75, length of septa: 7;
Range: length (without apex): 64--87, width: 64-90, length of septa: 4-8.
Remarks:
A? monteiliae sp. n. differs from the other species of the genus generally by the construction of the cingulum and existence of opercula in palynological material. The other species have six rectilinear cingular ridges each of which has of its two ends a slender process with bifurcate tip. In no one of them a free operculum was encountered and the apex organization remained unknown. These features provoke me to refer A? monteiliae sp. n. tho the genus Amphorula with all proper reserves. For the rest (tabulation, archeopyle, open septa, ambitus) the new species resembles the type species A. metuelliptica. The latter has high distally flaring septa, peni/intratabular, open, more complicated entire, perforate, fenestrate or denticulate.
Occurrence:
Boreholes R-l Hajredin (depth 3279.2-3280 m, Late Tithonian, Glozene Fm.); R-2 Beglez (depth .3103 m, Pleven Fm., Late Tithonian, Crassicollaria Zone); R-1 Bardarski geran (depth 2848 m., Kaspican-Salas Fm., Berriasian); R-l Junak (Tica Fm., deptll 1395 m, Calpionella Zone, C. ulpilla Subzone the boundary Late Tithonian-Berriasian. depth 1498-1578 m, Late lithonian, Crassicollaria Zone, Himalayites (M.) Microcanthus Zone); R-3 Junak (depth 1675.4 m, Tica Fm., Late Tithonian); R-9 Bozvelijsko (depth 2297-2302 m, Tica Fm., Late Tithonian, Crassicollaria Zone); R-7 Sultanci (depth 1707-1742 m, Tica Fm., Late Tithonian, Crsssicollaria Zone); R-8 Sultanci (depth 1795 m, Tica Fm., Late Tithonian, Crassicollaria Zone); R.-3 Komostica (depth 2856-2861 m, Glozene Fm., Calpiollella Zone, C. alpina Subzone, the boundary Late Tithoniall-Berriasian); outcrop Mahala Popska, the vicinity of the town of Sevlievo, Zlatarica-Cerni Osam Fm., Late Tithonian, Paraulucosphinctes transitorius Zone, Malbosiceras chaperi Subzone.
Amphorulacysta? monteilii, (Dodekova, 1994, p.18–19, pl.1, figs.6–11,13–14; pl.2, figs.6–10; text-figs.4a–b) Williams and Fensome, 2016, p.139.
Holotype: Dodekova, 1994, pl.1, figs.13–14.
Originally Amphorula? (generic name illegitimate), subsequently (and now) Amphorulacysta?
Questionable assignment: Williams and Fensome (2016, p.139).
Age: late Tithonian–Berriasian.
Locus typicus: outcrop Mahala Popska, vicinity of the town of Sevlievo, Central North Bulgaria
---------------------------------------------------------------------------------------------------
Original description: [Dodekova 1994, p. 18-19]:
Diagnosis:
The cyst is subspherical proximochorate-septate. The tabulation is gonyaulacacean indicted by low penitabular septa which may be arcuate semi-elliptical, semicircular to rectangular or polygonal in outline. Adcingular septa always open toward.s the cingulum. The cingulum is expressed by 6 pairs low subconical processes.
The archeopyle is apical, with deep accessory sutures and a sulcal notch. The operculum is free.
Description:
Acavate cyst. The cyst wall is composed of two appressed layers except where penitabular septa are formed. The superficial sculpture of the wall is illdefined. It consists of irregularly spaced, granules, pits, fine reticulum or smooth.
The tabulation repeats the classical gonyaulacacean pattern (Fig. 4) with a formula: 1-2 pr?, 4", 6", 6c, 6"", 1p, 1""", 5s.
The penitabular projections proximally start with thick ridges, striated, with or without rare perforations, which pass in thin septa (fig. 3, pl. 2, fig. 10). Distally the septa are entire or with rare denticulations and sporadic perforations. Monteil (1990, p. 598, pl. 1, figs. 2-4) very well described the apex organisation. There are 1 or 2 preapical plates (pl. I, figs. 8, 10; Monteil, 1990 pl. I, figs. 4a, b). In the centre of some opercula have subconical thicker place or group of granules. The four apical plates are arcuate or angular. Their form and dimensions are evident on the photos (pl I, figs. 7-11). The apical septa are always open towards preapical area but in some opercula the basal ridges may be closed (pl. 1, fig;. 7, 8). A great number of free opercula exists in palynological slides. They are so characteristic of the species that may be used for its identification. The adcingular series of plates possess arcuate-angular semi-elliptical, trapezoidal or semicircular septa, always open towards the cingulum. The septa of 1"", 6", 2"" and 6"" are relatively smaller than the others. The plate 1"" is the smallest, elliptic-angular with clear arcuate ridge septum towards the plate 2"", poorly, developed or absent towards the sulcus. The posterior plate -1p is polygonal with always closed septum. The single antapical plate 1"" is occupied by closed septum rounded six-sided or trapezoidal, asymmetric.
The cingulum is indicated by six pairs low subconical rectilinear processes, never with bifurcate tips. Their bases are not connected with the ridges as it is in the type species A. metaelliptica (pl. I, fig. 14; pl. 2, fig. 10). On rare occasions they may be connected with an allusion of ridges with the neighbour septa. It is often difficult to distinguish the cingular processes.
The sulcus (Fig. 4) is presented by low ridges with or without septa and includes: as- relatively large triangular open ridge; ras_small irregular-trapezoidal ridge; rs- and ls- clear, small arcuate ridges disposed opposite; pv (pr) - relatively large semi-elliptic open ridge with a low septum (pl. 2, fig. 7).
The morphological details of this species are observed on the well preserved specimens. The cysts are often broken or distorted to some extent, with secondary folds but the characteristic morphology permits their identification by the parts of the cyst. The intraspecific variability of the new species is expressed by insignificant variations of dimensions, the length of the septa varies in different specimens. The open ends of the ridges and septa in precingular and postcingular series normally are subparallel. But in some cysts the ends of neighbouring basal ridges converge one to other and rare are united. On another occasion the basal precingular ridges cross the cingulum and unit with the opposite postcingular ridges. Whether these instances are owing to the intraspecific variability or are provoked by deformation of the cyst is difficult to establish.
Dimensions (in µm):
Holotype: length without apex): 75, width: 75, length of septa: 7;
Range: length (without apex): 64--87, width: 64-90, length of septa: 4-8.
Remarks:
A? monteiliae sp. n. differs from the other species of the genus generally by the construction of the cingulum and existence of opercula in palynological material. The other species have six rectilinear cingular ridges each of which has of its two ends a slender process with bifurcate tip. In no one of them a free operculum was encountered and the apex organization remained unknown. These features provoke me to refer A? monteiliae sp. n. tho the genus Amphorula with all proper reserves. For the rest (tabulation, archeopyle, open septa, ambitus) the new species resembles the type species A. metuelliptica. The latter has high distally flaring septa, peni/intratabular, open, more complicated entire, perforate, fenestrate or denticulate.
Occurrence:
Boreholes R-l Hajredin (depth 3279.2-3280 m, Late Tithonian, Glozene Fm.); R-2 Beglez (depth .3103 m, Pleven Fm., Late Tithonian, Crassicollaria Zone); R-1 Bardarski geran (depth 2848 m., Kaspican-Salas Fm., Berriasian); R-l Junak (Tica Fm., deptll 1395 m, Calpionella Zone, C. ulpilla Subzone the boundary Late Tithonian-Berriasian. depth 1498-1578 m, Late lithonian, Crassicollaria Zone, Himalayites (M.) Microcanthus Zone); R-3 Junak (depth 1675.4 m, Tica Fm., Late Tithonian); R-9 Bozvelijsko (depth 2297-2302 m, Tica Fm., Late Tithonian, Crassicollaria Zone); R-7 Sultanci (depth 1707-1742 m, Tica Fm., Late Tithonian, Crsssicollaria Zone); R-8 Sultanci (depth 1795 m, Tica Fm., Late Tithonian, Crassicollaria Zone); R.-3 Komostica (depth 2856-2861 m, Glozene Fm., Calpiollella Zone, C. alpina Subzone, the boundary Late Tithoniall-Berriasian); outcrop Mahala Popska, the vicinity of the town of Sevlievo, Zlatarica-Cerni Osam Fm., Late Tithonian, Paraulucosphinctes transitorius Zone, Malbosiceras chaperi Subzone.