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Ternia balmei
Ternia balmei Helby and Stover, 1987
Holotype: Helby and Stover, 1987, figs.4A-C
Paratypes: Helby and Stover, 1987
Locus typicus: Investigator-1 well (20¦21'07.08"S, 112¦58'15.60"E), Exmouth Plateau, offshore Western Australia; unnamed unit at 3260 m;
Stratum typicum: Latest Bathonian-middle Callovian
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Ternia balmei Helby and Stover, 1987a. Ternia balmei possibly has an apical archeopyle. Extending out from the anterior subapical and ventral surfaces are relatively widely spaced trabeculae; each pair merging posteroventally into a single trabecula, one on each side of the cyst, supported by a trabecular network projecting outward from the posterior surface; similarly constructed, single or paired, trabecular structure(s) extending along all or part of the dorsal surface. T. balmei has a range of latest Bathonian to Mid Callovian. Size: length 70-114 µm, greatest diameter 35-70 µm.
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Original description: Helby and Stover 1987, p.135-136, 138
Longitudinally elongate, proximochorate cysts with a thin, smooth, single walled, asymmetrical body with outline in lateral view subquadrate (IHelby and Stover, 1987] Figs 2, 3D,E), with 2 shorter, straight to gently convex sides (anterior and ventral), and two, longer sides (a slightly convex posterior side and a generally concave dorsal side). Ventral corners obtusely rounded, dorsal corners are acutely rounded. Body outline in apicalantapical view subcircular to broadly elliptical ([Helby and Stover, 1987] Figs 2B, 3A,B,F); when the latter, the longer axis dorsoventral. A ring of relatively widely spaced, simple to complexly branched, solid processes arising from the gently convex subapical anterior surface, and supporting 2 (one anterior, one posterior), subparallel, relatively closely spaced trabeculae ([Helby and Stover, 1987] Figs 2A-C, 3A,B). Processes 15-22 µm long, and 1.5-7 µm wide at about midlength; trabeculae slightly more than 1 to about 2.5 µm wide, and may be connected by slender crossbars, or less commonly space between them filled in locally. Trabeculae with minute, generally widely and irregularly spaced denticles. Paired trabeculae bent posteriorly at ventral anterior corner ([Helby and Stover, 1987] Fig.2A,C), and continuing posteriorly along each side of the ventral surface to ventral posterior corner where each pair merges with a single posterior trabecula ([Helby and Stover, 1987] Figs 2C, 3D,E), and on some specimens, with a transverse trabecula ([Helby and Stover, 1987] Fig.2C). Ventral trabeculae usually with fewer crossbars, and fewer, less complex supporting structures than anterior ones.
Each side of the posterior surface flanked by a flange-like structure composed of a trabecular network of variable complexity ([Helby and Stover, 1987] Fig.3C,E,I), connected distally by a continuous trabeculum with numerous, closely spaced denticles ([Helby and Stover, 1987] Fig.3D,F,I), or only a few denticles, or surface smooth ([Helby and Stover, 1987] Fig.3C,E). Two posterior, flange-like structures may continue for a short distance onto dorsal surface then diminish in height and terminate, or less commonly, extend to the dorsal anterior corner ([Helby and Stover, 1987] Fig. 3C). On many specimens they merge at or near the dorsal posterior corner, and form a single flange-like feature which extends onto the dorsal surface ([Helby and Stover, 1987] Figs. 2A, 3D,E), decreasing in height, and terminating a short distance from the dorsal posterior comer, or reduced to a single trabecula with a few short supports and ending near the dorsal anterior corner. Anterior surface with an apical archeopyle; exact outline and paraplate equivalence of archeopyle undetermined ([Helby and Stover, 1987] Figs. 2B, 3B). Opening may be 5- or 6-sided with 2 long lateral sides, a short dorsal side, and 2 or 3 short ventral sides. Paratabulation not evident on the cysts with the possible exceptions of the archeopyle and the anterior processes, which could be intratabular. Measurements of 50 specimens are: length, 70 (80) 114 µm, greatest diameter 35 (56) 70 µm.
Holotype: Helby and Stover, 1987, figs.4A-C
Paratypes: Helby and Stover, 1987
Locus typicus: Investigator-1 well (20¦21'07.08"S, 112¦58'15.60"E), Exmouth Plateau, offshore Western Australia; unnamed unit at 3260 m;
Stratum typicum: Latest Bathonian-middle Callovian
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Ternia balmei Helby and Stover, 1987a. Ternia balmei possibly has an apical archeopyle. Extending out from the anterior subapical and ventral surfaces are relatively widely spaced trabeculae; each pair merging posteroventally into a single trabecula, one on each side of the cyst, supported by a trabecular network projecting outward from the posterior surface; similarly constructed, single or paired, trabecular structure(s) extending along all or part of the dorsal surface. T. balmei has a range of latest Bathonian to Mid Callovian. Size: length 70-114 µm, greatest diameter 35-70 µm.
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Original description: Helby and Stover 1987, p.135-136, 138
Longitudinally elongate, proximochorate cysts with a thin, smooth, single walled, asymmetrical body with outline in lateral view subquadrate (IHelby and Stover, 1987] Figs 2, 3D,E), with 2 shorter, straight to gently convex sides (anterior and ventral), and two, longer sides (a slightly convex posterior side and a generally concave dorsal side). Ventral corners obtusely rounded, dorsal corners are acutely rounded. Body outline in apicalantapical view subcircular to broadly elliptical ([Helby and Stover, 1987] Figs 2B, 3A,B,F); when the latter, the longer axis dorsoventral. A ring of relatively widely spaced, simple to complexly branched, solid processes arising from the gently convex subapical anterior surface, and supporting 2 (one anterior, one posterior), subparallel, relatively closely spaced trabeculae ([Helby and Stover, 1987] Figs 2A-C, 3A,B). Processes 15-22 µm long, and 1.5-7 µm wide at about midlength; trabeculae slightly more than 1 to about 2.5 µm wide, and may be connected by slender crossbars, or less commonly space between them filled in locally. Trabeculae with minute, generally widely and irregularly spaced denticles. Paired trabeculae bent posteriorly at ventral anterior corner ([Helby and Stover, 1987] Fig.2A,C), and continuing posteriorly along each side of the ventral surface to ventral posterior corner where each pair merges with a single posterior trabecula ([Helby and Stover, 1987] Figs 2C, 3D,E), and on some specimens, with a transverse trabecula ([Helby and Stover, 1987] Fig.2C). Ventral trabeculae usually with fewer crossbars, and fewer, less complex supporting structures than anterior ones.
Each side of the posterior surface flanked by a flange-like structure composed of a trabecular network of variable complexity ([Helby and Stover, 1987] Fig.3C,E,I), connected distally by a continuous trabeculum with numerous, closely spaced denticles ([Helby and Stover, 1987] Fig.3D,F,I), or only a few denticles, or surface smooth ([Helby and Stover, 1987] Fig.3C,E). Two posterior, flange-like structures may continue for a short distance onto dorsal surface then diminish in height and terminate, or less commonly, extend to the dorsal anterior corner ([Helby and Stover, 1987] Fig. 3C). On many specimens they merge at or near the dorsal posterior corner, and form a single flange-like feature which extends onto the dorsal surface ([Helby and Stover, 1987] Figs. 2A, 3D,E), decreasing in height, and terminating a short distance from the dorsal posterior comer, or reduced to a single trabecula with a few short supports and ending near the dorsal anterior corner. Anterior surface with an apical archeopyle; exact outline and paraplate equivalence of archeopyle undetermined ([Helby and Stover, 1987] Figs. 2B, 3B). Opening may be 5- or 6-sided with 2 long lateral sides, a short dorsal side, and 2 or 3 short ventral sides. Paratabulation not evident on the cysts with the possible exceptions of the archeopyle and the anterior processes, which could be intratabular. Measurements of 50 specimens are: length, 70 (80) 114 µm, greatest diameter 35 (56) 70 µm.