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Endoceratium turneri
Endoceratium turneri (Cookson and Eisenack, 1958) Stover and Evitt, 1978
Originally Pseudoceratium, subsequently (and now) Endoceratium.
Helby, 1987, retained this species in Pseudoceratium Gocht, 1957. Lentin and Williams, 1989, retained it in Endoceratium.
Holotype: Cookson and Eisenack, 1958, pl.5, fig.3
Paratypes: Cookson and Eisenack, 1958
Locus typicus: Gearle Siltstone, Carnarvon Basin, W Australia
Stratum typicum: Aptian-Albian
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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.
Endoceratium turneri (Cookson and Eisenack, 1958) Stover and Evitt, 1978. According to Morgan (1980, p.31), E.turneri has a convex subtriangular pericyst with longer apical horn and two widely divergent antapical horns or a rounded base and one antapical horn. The ornament consists of fibrous processes which may unite distally to form perforate striate crests, may unite along their whole length to form striate fibrous crests, and may support a complete or incomplete distal ectophragm, usually perforate. Proximally, the aligned process bases may be parasutural, defining gonyaulacacean tabulation, or may be non-tabular. Distally the supported ectophragm may be discontinuous, restricted to intratabular areas, and absent along the parasutures. Fibrous ornament variable in height, 5-12 µm over most of the cyst surface, but longer at the horns. Morgan (1980) recognized an evolutionary sequence in the development of the ornamentation. Size: Type 180 x 100 µm, apical horn 55 µm.
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Original description: Cookson and Eisenack, 1958: Pseudoceratium turneri
Test either subtriangular with an oblique base and convex sides, prolonged into three horns of unequal length, a longer apical horn and two widely seperated divergent antapikal horns, or with a rounded base and one antapical horn. Frequently the apical of the body becomes detached near the base of the apical horn.
The ornament usually takes the form of narrow lamella-like membranes with irregular, frequently curved outlines of variable lengths fomed by the distal coalescence of short bifurcate processes, the lamellae either remainingfree or uniting to form a more or less complete network.
Dimensions: Type 180x100 µm overall; apical horn 55 µm.
Supplemental description: Morgan, 1980, p. 31: Pseudoceratium turneri
Single-layered cyst usually subtriangular with convex sides, to subrhombic; autophragm usually drawn into one apical and one antapical subconical horn, with a broadly rounded bulge forming the single lateral horn, arising at the cingulum and pointed antapically; occasionally the second antapical horn, and the second lateral horn are marked by broad bulges, creating a roughly pentagonal cyst body.
Fibrous processes arise from the autophragm, may unite distally to form perforate striate crests, may untie along their whole length to form striate fibrous crests, and may support a complete or incomplete distal ectophragm, usually perforate; proximally the aligned process bases may be parasutural, defining a gonyaulacean tabulation, or may be non-tabular; distally, the supported ectophragm may be discontinuous, resticted to intertabular areas, and absent along the parasutures; fibrous ornament very variable in hight, 5-12 Ám over most of the crest surface, but longer at the horns. Archaeopyle apical, operculum free.
Originally Pseudoceratium, subsequently (and now) Endoceratium.
Helby, 1987, retained this species in Pseudoceratium Gocht, 1957. Lentin and Williams, 1989, retained it in Endoceratium.
Holotype: Cookson and Eisenack, 1958, pl.5, fig.3
Paratypes: Cookson and Eisenack, 1958
Locus typicus: Gearle Siltstone, Carnarvon Basin, W Australia
Stratum typicum: Aptian-Albian
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Endoceratium turneri (Cookson and Eisenack, 1958) Stover and Evitt, 1978. According to Morgan (1980, p.31), E.turneri has a convex subtriangular pericyst with longer apical horn and two widely divergent antapical horns or a rounded base and one antapical horn. The ornament consists of fibrous processes which may unite distally to form perforate striate crests, may unite along their whole length to form striate fibrous crests, and may support a complete or incomplete distal ectophragm, usually perforate. Proximally, the aligned process bases may be parasutural, defining gonyaulacacean tabulation, or may be non-tabular. Distally the supported ectophragm may be discontinuous, restricted to intratabular areas, and absent along the parasutures. Fibrous ornament variable in height, 5-12 µm over most of the cyst surface, but longer at the horns. Morgan (1980) recognized an evolutionary sequence in the development of the ornamentation. Size: Type 180 x 100 µm, apical horn 55 µm.
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Original description: Cookson and Eisenack, 1958: Pseudoceratium turneri
Test either subtriangular with an oblique base and convex sides, prolonged into three horns of unequal length, a longer apical horn and two widely seperated divergent antapikal horns, or with a rounded base and one antapical horn. Frequently the apical of the body becomes detached near the base of the apical horn.
The ornament usually takes the form of narrow lamella-like membranes with irregular, frequently curved outlines of variable lengths fomed by the distal coalescence of short bifurcate processes, the lamellae either remainingfree or uniting to form a more or less complete network.
Dimensions: Type 180x100 µm overall; apical horn 55 µm.
Supplemental description: Morgan, 1980, p. 31: Pseudoceratium turneri
Single-layered cyst usually subtriangular with convex sides, to subrhombic; autophragm usually drawn into one apical and one antapical subconical horn, with a broadly rounded bulge forming the single lateral horn, arising at the cingulum and pointed antapically; occasionally the second antapical horn, and the second lateral horn are marked by broad bulges, creating a roughly pentagonal cyst body.
Fibrous processes arise from the autophragm, may unite distally to form perforate striate crests, may untie along their whole length to form striate fibrous crests, and may support a complete or incomplete distal ectophragm, usually perforate; proximally the aligned process bases may be parasutural, defining a gonyaulacean tabulation, or may be non-tabular; distally, the supported ectophragm may be discontinuous, resticted to intertabular areas, and absent along the parasutures; fibrous ornament very variable in hight, 5-12 Ám over most of the crest surface, but longer at the horns. Archaeopyle apical, operculum free.