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Thalassiphora inflata
Thalassiphora inflata Heilmann-Clausen in Thomsen and Heilmann-Clausen, 1985
Originally (and now) Thalassiphora, subsequently Flandrecysta (name not validly published).
Holotype: Thomsen and Heilmann-Clausen, 1985, pl.7, figs.5-6; text-figs.11C-D
Age: Paleocene (Danian-early Selandian)
Original description (Thomsen and Heilmann-Clausen, 1985):
Thalassiphora inflata sp. nov. Fig. 11, pi. 7, figs 3-8.
Derivation of name. Latin, inflatus, with reference to the inflated appearance of the peripragm in most of the epicyst.
Diagnosis. The endocyst is ovoid. The periphragm is closely apressed to the endophragm except in the apical, ventral and lateral parts of the epicyst and on the ventral part of the postcingular zone where wall layers are widely separated by a prominent pericoel. The pericoel communicates with the exterior through a large hole in the mid-ventral part of the periphragm. Wall layers are thin and smooth. Low indistinct processes may be present in the ventral part of the hypocyst. A few spines may be present along the paracingulum. A long spine-shaped protusion of the paracingular suture is present in the right margin of the ventral hole in the periphram. Paratabulation is expressed as a precingular archaeopyle representing paraplate 3" , and as parasutural lines or low ridges, indicating the paraplates IM ' and most of the paracingulum. Other faint lines on the expanded part of the periphragm may possibly represent parasuturcs, irregular features or folds in the flexible wall. The ventral hole in the periphragm intersects the paracingulum which is otherwise continuous. A parasulcus is therefore wholly or partly included in the ventral hole in the periphragm.
Holotype. Fig. IIC, D, pi. 7, figs 5, 6. MGUH 16155, England finder coordinates W 30/4. Dimensions: Endocyst length — 32 µm, breadth - 30 µm. Pericyst length = 48 µm, breadth = 54 µm.
Type locality and type stratum: Denmark, Svejstrup, Kerteminde Marl, sample SV 8.
Paratypes. Fig. IIA, B, pi. 7, figs 3, 4. MGUH 16156, coordinates O 35/2. PI. 7, figs 7, 8. MGLIH 16157, coordinates R 40/ 3.
Discussion. Thalassiphora inflata sp. nov. resembles 7". delicata Williams & Downie. It is distinguished on the absence of pericoel in the antapical area and furthermore by a different position of the ventral hole in the periphragm. In T. delicata the hole represents paraplate 1" according to Eaton (1976) and Manum (1979). T. inflata shows affinities also to the genus Lophocysta Manum, since the percoel in Lophocysta is only developed over a limited part of the endocyst. T. inflata differs, however, in the presence of a large hole in the periphragm in the parasulcal area.
Occurrence. Danian and Lower Selandian, Denmark.
Originally (and now) Thalassiphora, subsequently Flandrecysta (name not validly published).
Holotype: Thomsen and Heilmann-Clausen, 1985, pl.7, figs.5-6; text-figs.11C-D
Age: Paleocene (Danian-early Selandian)
Original description (Thomsen and Heilmann-Clausen, 1985):
Thalassiphora inflata sp. nov. Fig. 11, pi. 7, figs 3-8.
Derivation of name. Latin, inflatus, with reference to the inflated appearance of the peripragm in most of the epicyst.
Diagnosis. The endocyst is ovoid. The periphragm is closely apressed to the endophragm except in the apical, ventral and lateral parts of the epicyst and on the ventral part of the postcingular zone where wall layers are widely separated by a prominent pericoel. The pericoel communicates with the exterior through a large hole in the mid-ventral part of the periphragm. Wall layers are thin and smooth. Low indistinct processes may be present in the ventral part of the hypocyst. A few spines may be present along the paracingulum. A long spine-shaped protusion of the paracingular suture is present in the right margin of the ventral hole in the periphram. Paratabulation is expressed as a precingular archaeopyle representing paraplate 3" , and as parasutural lines or low ridges, indicating the paraplates IM ' and most of the paracingulum. Other faint lines on the expanded part of the periphragm may possibly represent parasuturcs, irregular features or folds in the flexible wall. The ventral hole in the periphragm intersects the paracingulum which is otherwise continuous. A parasulcus is therefore wholly or partly included in the ventral hole in the periphragm.
Holotype. Fig. IIC, D, pi. 7, figs 5, 6. MGUH 16155, England finder coordinates W 30/4. Dimensions: Endocyst length — 32 µm, breadth - 30 µm. Pericyst length = 48 µm, breadth = 54 µm.
Type locality and type stratum: Denmark, Svejstrup, Kerteminde Marl, sample SV 8.
Paratypes. Fig. IIA, B, pi. 7, figs 3, 4. MGUH 16156, coordinates O 35/2. PI. 7, figs 7, 8. MGLIH 16157, coordinates R 40/ 3.
Discussion. Thalassiphora inflata sp. nov. resembles 7". delicata Williams & Downie. It is distinguished on the absence of pericoel in the antapical area and furthermore by a different position of the ventral hole in the periphragm. In T. delicata the hole represents paraplate 1" according to Eaton (1976) and Manum (1979). T. inflata shows affinities also to the genus Lophocysta Manum, since the percoel in Lophocysta is only developed over a limited part of the endocyst. T. inflata differs, however, in the presence of a large hole in the periphragm in the parasulcal area.
Occurrence. Danian and Lower Selandian, Denmark.