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Adnatosphaeridium ivoirense
From Fensome et al., 2019:
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Original description Awad and Oboh-Ikenobe, 2016:
Adnatosphaeridium ivoriense sp. nov. Plate I, 1-5
Holotype: ODP Hole 959D, 803.12 mbsf, sample CIG5, slide MST-1915-S13, EF M11/3, Late Paleocene. Plate I; 1e4.
Paratype: ODP Hole 959D, 806.30 mbsf, sample CIG6, slide MST- 1915-S18, EF J25/2, Late Paleocene. Plate I; 5.
Type locality: Upper Paleocene of ODP Hole 959D, Côte d’Ivoire-Ghana Transform Margin, West Africa. Lithological unit III (Shipboard Scientific Party, 1996).
Etymology: After the country of Côte d’Ivoire.
Synonymy: Adnatosphaeridium sp. A (Jan du Chêne and Adediran, 1985) plate 23, 1e6.
Diagnosis: A species of Adnatosphaeridium with short processes, which are connected by distal trabeculae that are finely perforate.
Description: Skolochorate cyst with a subspherical body. The processes are simple, intratabular, arranged in soleate or annulate groups that reflect the paratabulation of the cyst. Each complex composes of very fine and short processes, which are united distally by trabeculae that are joined to each other and look distally like a reticulate or a finely perforate membrane. The species is characterized by a well-developed antapical proturbance and the sulcus is offset to the left (Plate I; 2), this feature would agree with the areoligeran nature of this genus (Fensome et al., 1993). Archaeopyle is apical type tA; operculum free.
Dimensions: Holotype: width x length: 80 70 mm; length of processes 15 mm. Paratype: width x length: 57 71 mm; length of processes 10e14 mm. 2 specimens measured.
Stratigraphic range: Adnatosphaeridium ivoriense sp. nov. was observed in ODP Hole 959D from 803.12 mbsf to 806.3 mbsf (Late Paleocene). This new species is restricted to the late Thanetian–early Ypresian as recorded from a previous study of the Imo Formation in Nigeria by Jan du Ch^ene and Adediran (1985). Adnatosphaeridium ivoriense sp. nov. is rare (2 specimens) and has a relatively short stratigraphic range in the studied interval. This observation is similar to that reported by Jan du Ch^ene and Adediran (1985) who recorded three specimens of this species in the Late Paleocene-Early Eocene interval.
Comparison: Adnatosphaeridium ivoriense sp. nov. differs from other species of this genus by its shorter processes. Processes are united by distal trabecula, which are finely perforate and wider than those of other species. Adnatosphaeridium? membraniphorum (Jan du Chêne and Adediran, 1985) and Adnatosphaeridium multispinosum (Williams and Downie, 1966) both have longer processes (20–36 µm) with central body diameters 56–68 µm to 54–76 µm, respectively. In addition, the former has clearer perforations than Adnatosphaeridium ivoriense sp. nov., while the later has only single trabecula of variable breadth without any perforations. A. vittatum (Williams and Downie, 1966) has processes showing considerable variation in breadth (up to 20 mm) with length up to 30 mm, central body diameter 35–48 µm and distally united by interconnecting ribbon-like trabecula, which are broad and membranous. In Adnatosphaeridium robustum (Morgenroth, 1966) length of processes is up to 26 mm with acuminate spines occasionally present on the trabecula without perforations like the new species. Adnatosphaeridium williamsii Islam, 1983) differs from Adnatosphaeridium ivoriense sp. nov. in having filiform extremities (up to 20 µm process length, 43–57 µm body diameter). Both Adnatosphaeridium buccinum (Hultberg, 1985; length of processes 22 µm, cyst diameter 40 µm) and Adnatosphaeridium caulleryi (Deflandre, 1939; length of processes 10–17 µm, cyst diameter 45 µm) differ from the new species by buccinate processes that are connected with distal trabecula without perforation. Adnatosphaeridium densifilosum (Cookson and Eisenack, 1974) has denser fenestrate trabecula with very long processes (up to 45 µm) and 45 µm cyst diameter. Small filiforms at the trabecula are the major characteristics of Adnatosphaeridium filiferum (Cookson and Eisenack, 1958, up to 50 µm length of processes and 104 µm cyst diameter). Glaphyrocysta exuberans (Deflandre and Cookson, 1955), Glaphyrocysta microfenestrata (Bujak, 1976) and Glaphyrocysta vicina (Eaton, 1976) do not have process complexes in the mid-ventral and mid-dorsal areas. The processes of Adnatosphaeridium ivoriense sp. nov. are not connected proximally by basal ridges that mainly characterize Areoligera spp.
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Original description Awad and Oboh-Ikenobe, 2016:
Adnatosphaeridium ivoriense sp. nov. Plate I, 1-5
Holotype: ODP Hole 959D, 803.12 mbsf, sample CIG5, slide MST-1915-S13, EF M11/3, Late Paleocene. Plate I; 1e4.
Paratype: ODP Hole 959D, 806.30 mbsf, sample CIG6, slide MST- 1915-S18, EF J25/2, Late Paleocene. Plate I; 5.
Type locality: Upper Paleocene of ODP Hole 959D, Côte d’Ivoire-Ghana Transform Margin, West Africa. Lithological unit III (Shipboard Scientific Party, 1996).
Etymology: After the country of Côte d’Ivoire.
Synonymy: Adnatosphaeridium sp. A (Jan du Chêne and Adediran, 1985) plate 23, 1e6.
Diagnosis: A species of Adnatosphaeridium with short processes, which are connected by distal trabeculae that are finely perforate.
Description: Skolochorate cyst with a subspherical body. The processes are simple, intratabular, arranged in soleate or annulate groups that reflect the paratabulation of the cyst. Each complex composes of very fine and short processes, which are united distally by trabeculae that are joined to each other and look distally like a reticulate or a finely perforate membrane. The species is characterized by a well-developed antapical proturbance and the sulcus is offset to the left (Plate I; 2), this feature would agree with the areoligeran nature of this genus (Fensome et al., 1993). Archaeopyle is apical type tA; operculum free.
Dimensions: Holotype: width x length: 80 70 mm; length of processes 15 mm. Paratype: width x length: 57 71 mm; length of processes 10e14 mm. 2 specimens measured.
Stratigraphic range: Adnatosphaeridium ivoriense sp. nov. was observed in ODP Hole 959D from 803.12 mbsf to 806.3 mbsf (Late Paleocene). This new species is restricted to the late Thanetian–early Ypresian as recorded from a previous study of the Imo Formation in Nigeria by Jan du Ch^ene and Adediran (1985). Adnatosphaeridium ivoriense sp. nov. is rare (2 specimens) and has a relatively short stratigraphic range in the studied interval. This observation is similar to that reported by Jan du Ch^ene and Adediran (1985) who recorded three specimens of this species in the Late Paleocene-Early Eocene interval.
Comparison: Adnatosphaeridium ivoriense sp. nov. differs from other species of this genus by its shorter processes. Processes are united by distal trabecula, which are finely perforate and wider than those of other species. Adnatosphaeridium? membraniphorum (Jan du Chêne and Adediran, 1985) and Adnatosphaeridium multispinosum (Williams and Downie, 1966) both have longer processes (20–36 µm) with central body diameters 56–68 µm to 54–76 µm, respectively. In addition, the former has clearer perforations than Adnatosphaeridium ivoriense sp. nov., while the later has only single trabecula of variable breadth without any perforations. A. vittatum (Williams and Downie, 1966) has processes showing considerable variation in breadth (up to 20 mm) with length up to 30 mm, central body diameter 35–48 µm and distally united by interconnecting ribbon-like trabecula, which are broad and membranous. In Adnatosphaeridium robustum (Morgenroth, 1966) length of processes is up to 26 mm with acuminate spines occasionally present on the trabecula without perforations like the new species. Adnatosphaeridium williamsii Islam, 1983) differs from Adnatosphaeridium ivoriense sp. nov. in having filiform extremities (up to 20 µm process length, 43–57 µm body diameter). Both Adnatosphaeridium buccinum (Hultberg, 1985; length of processes 22 µm, cyst diameter 40 µm) and Adnatosphaeridium caulleryi (Deflandre, 1939; length of processes 10–17 µm, cyst diameter 45 µm) differ from the new species by buccinate processes that are connected with distal trabecula without perforation. Adnatosphaeridium densifilosum (Cookson and Eisenack, 1974) has denser fenestrate trabecula with very long processes (up to 45 µm) and 45 µm cyst diameter. Small filiforms at the trabecula are the major characteristics of Adnatosphaeridium filiferum (Cookson and Eisenack, 1958, up to 50 µm length of processes and 104 µm cyst diameter). Glaphyrocysta exuberans (Deflandre and Cookson, 1955), Glaphyrocysta microfenestrata (Bujak, 1976) and Glaphyrocysta vicina (Eaton, 1976) do not have process complexes in the mid-ventral and mid-dorsal areas. The processes of Adnatosphaeridium ivoriense sp. nov. are not connected proximally by basal ridges that mainly characterize Areoligera spp.