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Subtilisphaera kalaalliti
Subtilisphaera kalaalliti Nohr-Hansen 1993
Holotype: Nohr-Hansen 1993: Plate 26, Figs 1 & 2
Locus typicus: Section 30, Tvaerdal, Geographical Society 0, East Greenland.
Stratum typicum: Upper Albian
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999
Subtilisphaera kalaalliti Nøhr-Hansen, 1993. Diagnosis from Nøhr-Hansen (1993, p.114), the species is represented by thin-walled pentagonal partly hypocavate cysts. Epicyst long, conical tapering from the cingulum; hypocyst short with one broad-based antapical horn. A presumed intercalary archeopyle is seldom observed, whereas a secondary opening, an opisthopyle, is almost always present antapically. Epicyst almost twice length of hypocyst. endophragm and periphragm essentially smooth. There is a cingular fold. Size: pericyst length 60-85 µm, width 42-61 µm, length of antapical horn 8-14 µm.
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Original diagnosis: Nohr-Hansen 1993, p. 114
The species is represented by thin-walled pentagonal, partly hypocavate cysts. Epicyst long, conical, tapering from the cingulum; hypocyst short with one broad-based antapical horn. A presumed intercalary archeopyle is seldom observed, whereas a secondary opening, an opisthopyle, is almost always present antapically.
Description: Nohr-Hansen 1993, p. 114
Cyst type. Partly hypocavate cyst. Shape. Dorsoventrally compressed pentagonal cyst. Epicyst long (almost twice the length of the hypocyst), conical, tapering from the cingulum. Hypocyst short, angular, with one broad-based antapical horn. Wall relationships. Cyst wall two-layered, endophragm and periphragm closely appressed on the epicyst, cingulum and anterior part of the hypocyst, whereas a pericoel is present in the antapical part of the hypocyst (including the horn). Wall features. Endophragm thin-walled, hyaline, with a psilate to shagreenate surface. Periphragm thin-walled, hyaline, also with an almost smooth surface. Tabulation. A cingular furrow has been distinguished between two periphragmal folds running almost parallel two thirds down the cysts. Archeopyle. A presumed intercalary archeopyle may be distinguished on a few specimens, whereas an antapical opening (an ophistopyle) next to the antapical horn, is almost always present.
Dimensions: (Measurements in µm.)
Holotype Range Specimens
Total length 74 60 (70) 85 9
Width 55 42 (47) 61 9
Length antapical horn 13 8 (10)14 9
Discussion. Subtilisphaera kalaallitl sp. nov. resembles in shape and size Cepadinium ventrio.sum (Alberti, 1959a) Lister & Batten, 1988, but differs trom the genus Cepadinium by being a double-walled cyst. The new species has been included in the genus Subtilisphaera, because of its two wall layers and cavatc nature, its weakly discernible archeopyle, and the absence of tabulation except for the low transverse equatorial folds or ridges that most likely indicate a cingulum. The species S. pirnaensis (Alberti, 1959a) Jain & Millepied, 1973 resembles S. kalaalliti in shape. but differs by being cavate to bicavate and by its slightly larger size. Palaeoperidinium cretaceum differs from S. kalaallitti by its slightly larger size, by having two conical antapical horns and by having a periphragm of similar shape as the endophragm.
Occurrence in East Greenland. Upper Albian.
Holotype: Nohr-Hansen 1993: Plate 26, Figs 1 & 2
Locus typicus: Section 30, Tvaerdal, Geographical Society 0, East Greenland.
Stratum typicum: Upper Albian
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999
Subtilisphaera kalaalliti Nøhr-Hansen, 1993. Diagnosis from Nøhr-Hansen (1993, p.114), the species is represented by thin-walled pentagonal partly hypocavate cysts. Epicyst long, conical tapering from the cingulum; hypocyst short with one broad-based antapical horn. A presumed intercalary archeopyle is seldom observed, whereas a secondary opening, an opisthopyle, is almost always present antapically. Epicyst almost twice length of hypocyst. endophragm and periphragm essentially smooth. There is a cingular fold. Size: pericyst length 60-85 µm, width 42-61 µm, length of antapical horn 8-14 µm.
--------------------------------------------------
Original diagnosis: Nohr-Hansen 1993, p. 114
The species is represented by thin-walled pentagonal, partly hypocavate cysts. Epicyst long, conical, tapering from the cingulum; hypocyst short with one broad-based antapical horn. A presumed intercalary archeopyle is seldom observed, whereas a secondary opening, an opisthopyle, is almost always present antapically.
Description: Nohr-Hansen 1993, p. 114
Cyst type. Partly hypocavate cyst. Shape. Dorsoventrally compressed pentagonal cyst. Epicyst long (almost twice the length of the hypocyst), conical, tapering from the cingulum. Hypocyst short, angular, with one broad-based antapical horn. Wall relationships. Cyst wall two-layered, endophragm and periphragm closely appressed on the epicyst, cingulum and anterior part of the hypocyst, whereas a pericoel is present in the antapical part of the hypocyst (including the horn). Wall features. Endophragm thin-walled, hyaline, with a psilate to shagreenate surface. Periphragm thin-walled, hyaline, also with an almost smooth surface. Tabulation. A cingular furrow has been distinguished between two periphragmal folds running almost parallel two thirds down the cysts. Archeopyle. A presumed intercalary archeopyle may be distinguished on a few specimens, whereas an antapical opening (an ophistopyle) next to the antapical horn, is almost always present.
Dimensions: (Measurements in µm.)
Holotype Range Specimens
Total length 74 60 (70) 85 9
Width 55 42 (47) 61 9
Length antapical horn 13 8 (10)14 9
Discussion. Subtilisphaera kalaallitl sp. nov. resembles in shape and size Cepadinium ventrio.sum (Alberti, 1959a) Lister & Batten, 1988, but differs trom the genus Cepadinium by being a double-walled cyst. The new species has been included in the genus Subtilisphaera, because of its two wall layers and cavatc nature, its weakly discernible archeopyle, and the absence of tabulation except for the low transverse equatorial folds or ridges that most likely indicate a cingulum. The species S. pirnaensis (Alberti, 1959a) Jain & Millepied, 1973 resembles S. kalaalliti in shape. but differs by being cavate to bicavate and by its slightly larger size. Palaeoperidinium cretaceum differs from S. kalaallitti by its slightly larger size, by having two conical antapical horns and by having a periphragm of similar shape as the endophragm.
Occurrence in East Greenland. Upper Albian.