Back
Palaecysta integra
Palaecysta integra Chen, 2013, p.289–290, pl.1, figs.1–6; pl.2, figs.16–20; pl.5, figs.51–58; text-figs.5A–C; text-figs.9, nos.5,7,11,14; text-figs.10, nos.31,38, text-figs.11, nos.64–65,67.
Holotype: Chen, 2013, pl.1, fig.1.
Age: late Tithonian–Berriasian.
Original description (Chen, 2013):
Palaecysta integra sp. nov. integra,
Latin, entire, depicting the completeness (no branching) nature of the membranous pre- and post-cingular process clusters.
Holotype. Plate 1, Figure 1, Slide 1316-25, U62
Paratype. Plate 1, Figure 2, Slide 1316-25, T58
Other specimens. Plate 1, Figures 3-6; Plate 2, Figures 18-20.
Synonym. Amphorula? sp. B (Brenner 1992; Plate 2, Figures, 1, 2, 4, 5).
Synopsis Cysts skolochorate, gonyaulacacean, sexiform, comprising 18 membranous process clusters and up to 18 singular spinous processes, none of which are distally linked (Figure 5). The membranous process clusters arcuate in the apical, precingular, posterior intercalary, and postcingular series, annulate in the antapical series. The singular spinous processes are restricted to the parasulcus and the paracingular series. The anterior sulcal process is well-established (Figure 5B). Archeopyle apical (Figure 5C). Parasutural features present, expressed by accessory archeopyle sutures, of up to two-third of a paraplate length, in areas between precingular paraplates (Figure 5B). Processes and process clusters intratabular. Pre-apicals are expressed by granulate protrusions (Figure 5C). Process formula, gonyaulacacean: 0-3 pr, 4’, 6’’, 6c, 6’’’, 1p, 1’’’’, as, ps, 0- 7s. The five postcingular process clusters are interpreted to be from paraplates 2’’’ to 6’’’; and the 1’’’ is expressed by a long rectilinear process (Figures 5A, 5B). Paracingulum is indicated by six pairs of spinous processes, isolated, unlinked at the base.
Diagnosis: The largely intact nature of the membranous process clusters in the pre- and postcingular series, with one to two long cuts and numerous shallow slits (Figure 5; Figure 9, drawing 5; Figure 10, drawing 31; Figure 11, drawings 64, 65) is the main characteristic of this species.
Dimensions (based on measurements from 50 specimens):
Holotype – Whole specimen 135 µm; central body 81 µm; process length 43 µm
Range – Whole specimen 125 (135) 145 µm; central body 75 (81) 91 µm; process length 38 (43) 50 µm
Remarks: Although few shallow and deep cuts in the individual process clusters exist, this species has, by far, the most intact membrane observed for the genus; it also has the least branched process clusters. The four photomicrographs of Amphorula? sp. B, reported by Brenner (1992), clearly show long arcuate process clusters, along with other characteristics common to the genus Palaecysta; that species is, hence, herein transferred.
Occurrences in the Ankamotra-1 well. P. integra occurred consistently from 1226m to 1325m (Late Tithonian to Berriasian).
Holotype: Chen, 2013, pl.1, fig.1.
Age: late Tithonian–Berriasian.
Original description (Chen, 2013):
Palaecysta integra sp. nov. integra,
Latin, entire, depicting the completeness (no branching) nature of the membranous pre- and post-cingular process clusters.
Holotype. Plate 1, Figure 1, Slide 1316-25, U62
Paratype. Plate 1, Figure 2, Slide 1316-25, T58
Other specimens. Plate 1, Figures 3-6; Plate 2, Figures 18-20.
Synonym. Amphorula? sp. B (Brenner 1992; Plate 2, Figures, 1, 2, 4, 5).
Synopsis Cysts skolochorate, gonyaulacacean, sexiform, comprising 18 membranous process clusters and up to 18 singular spinous processes, none of which are distally linked (Figure 5). The membranous process clusters arcuate in the apical, precingular, posterior intercalary, and postcingular series, annulate in the antapical series. The singular spinous processes are restricted to the parasulcus and the paracingular series. The anterior sulcal process is well-established (Figure 5B). Archeopyle apical (Figure 5C). Parasutural features present, expressed by accessory archeopyle sutures, of up to two-third of a paraplate length, in areas between precingular paraplates (Figure 5B). Processes and process clusters intratabular. Pre-apicals are expressed by granulate protrusions (Figure 5C). Process formula, gonyaulacacean: 0-3 pr, 4’, 6’’, 6c, 6’’’, 1p, 1’’’’, as, ps, 0- 7s. The five postcingular process clusters are interpreted to be from paraplates 2’’’ to 6’’’; and the 1’’’ is expressed by a long rectilinear process (Figures 5A, 5B). Paracingulum is indicated by six pairs of spinous processes, isolated, unlinked at the base.
Diagnosis: The largely intact nature of the membranous process clusters in the pre- and postcingular series, with one to two long cuts and numerous shallow slits (Figure 5; Figure 9, drawing 5; Figure 10, drawing 31; Figure 11, drawings 64, 65) is the main characteristic of this species.
Dimensions (based on measurements from 50 specimens):
Holotype – Whole specimen 135 µm; central body 81 µm; process length 43 µm
Range – Whole specimen 125 (135) 145 µm; central body 75 (81) 91 µm; process length 38 (43) 50 µm
Remarks: Although few shallow and deep cuts in the individual process clusters exist, this species has, by far, the most intact membrane observed for the genus; it also has the least branched process clusters. The four photomicrographs of Amphorula? sp. B, reported by Brenner (1992), clearly show long arcuate process clusters, along with other characteristics common to the genus Palaecysta; that species is, hence, herein transferred.
Occurrences in the Ankamotra-1 well. P. integra occurred consistently from 1226m to 1325m (Late Tithonian to Berriasian).