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Lithodinia areolata
Lithodinia? areolata (Klement, 1960, p.76–77, pl.8, figs.5–9) Sarjeant, 1984a, p.166.
NOW Epiplosphaera?. Originally Epiplosphaera, subsequently Lithodinia?, thirdly (and now) Epiplosphaera?. At the time of the transfer, Sarjeant, 1984, questionably included this species in Lithodinia.
Brenner, 1988, retained the species in Epiplosphaera Klement, 1960.
Holotype: Klement, 1960, pl.8, fig.5-7
Paratypes: Klement, 1960
Locus typicus: Scherstetten 1 Well, SW Germany
Stratum typicum: Early Kimmeridgian
Translation Klement 1960: LPP
Original description: Klement, 1960, p. 76: Epiplosphaera areolata
Diagnosis: A species of the genus Epiplosphaera with ellipsoidal shell, of which the surface is fine-meshed and irregularly polygonal. Simple, short, thorn-like processes in linear arrangement on junctions of the basal network, rarely isolated, as a rule mutually connected by narrow bulges. These connections run, corresponding to process distribution, in a lineaar fashion in longitudinal and transversal directions, resulting in an areolation on the shell in the form of trapezoidal, joining structures on epi- and hypovalve.
Dimensions:
Holotype: L:B with processes 66:63 µm, L:B without processes 52:49 µm, process length 9-12 µm.
Paratypes: L:B with processes 72:66 and 66:61 µm, L:B without processes 52:49 and 52:49 µm, process length 12-15 and about 9 µm.
Diameter in polar view: L:B without processes: 50 µm, process length 10 µm.
Minimum: L:B with processes 60:55 µm, L:B without processes 46:43 µm, process length 7-8 µm.
Maximum: L:B with processes 83:79 µm, L:B without processes 63:57 µm, process length 11-12 µm.
Affinities:
Klement, 1960, p. 77
Epiplosphaera areolata differs from E. bireticulata in the absence of the ridge-network. It differs from E. reticulospinosa in the bulge-like, linearly arranged basal coalescence, which form closed structures and the absence of ridges, especially between the marginal processes.
Sarjeant, 1984, p. 166: Lithodinia areolata
Discussion: Typical members of the genus Epiplosphaera exhibit an overall areolation, with spines arising from the septa between the areolae. Cingulum and sulcus may be visible, but paratabulation - if developed at all - is masked by the complex overall pattern of septa.
The morphology of L. areolata is quite different. Cingulum, sulcus and paraplates are all clearly developed and accord with the familar gonyaulacoid pattern. The spines arise only from parasutural crests; the overall areolation is on a much smaller scale and there are no processes on the paraplates themselves. Since the species has spine rows rather than parasutural crests, it is here placed into Lithodinia; however, the nature of the operculum - whether thrown off as a unit or as two or more opercular pieces - remains to be determined. For this reason, the generic reallocation heree proposed is only prrovisional. In its basic paratabulation pattern and overall areolation, Lithodinia? areolata resembles Meiourogonyaulax araneosa Muir and Sarjeant, 1978. However, the crest spines of the latter species are much lower and its ventral paratabulation appears dissimilar.
NOW Epiplosphaera?. Originally Epiplosphaera, subsequently Lithodinia?, thirdly (and now) Epiplosphaera?. At the time of the transfer, Sarjeant, 1984, questionably included this species in Lithodinia.
Brenner, 1988, retained the species in Epiplosphaera Klement, 1960.
Holotype: Klement, 1960, pl.8, fig.5-7
Paratypes: Klement, 1960
Locus typicus: Scherstetten 1 Well, SW Germany
Stratum typicum: Early Kimmeridgian
Translation Klement 1960: LPP
Original description: Klement, 1960, p. 76: Epiplosphaera areolata
Diagnosis: A species of the genus Epiplosphaera with ellipsoidal shell, of which the surface is fine-meshed and irregularly polygonal. Simple, short, thorn-like processes in linear arrangement on junctions of the basal network, rarely isolated, as a rule mutually connected by narrow bulges. These connections run, corresponding to process distribution, in a lineaar fashion in longitudinal and transversal directions, resulting in an areolation on the shell in the form of trapezoidal, joining structures on epi- and hypovalve.
Dimensions:
Holotype: L:B with processes 66:63 µm, L:B without processes 52:49 µm, process length 9-12 µm.
Paratypes: L:B with processes 72:66 and 66:61 µm, L:B without processes 52:49 and 52:49 µm, process length 12-15 and about 9 µm.
Diameter in polar view: L:B without processes: 50 µm, process length 10 µm.
Minimum: L:B with processes 60:55 µm, L:B without processes 46:43 µm, process length 7-8 µm.
Maximum: L:B with processes 83:79 µm, L:B without processes 63:57 µm, process length 11-12 µm.
Affinities:
Klement, 1960, p. 77
Epiplosphaera areolata differs from E. bireticulata in the absence of the ridge-network. It differs from E. reticulospinosa in the bulge-like, linearly arranged basal coalescence, which form closed structures and the absence of ridges, especially between the marginal processes.
Sarjeant, 1984, p. 166: Lithodinia areolata
Discussion: Typical members of the genus Epiplosphaera exhibit an overall areolation, with spines arising from the septa between the areolae. Cingulum and sulcus may be visible, but paratabulation - if developed at all - is masked by the complex overall pattern of septa.
The morphology of L. areolata is quite different. Cingulum, sulcus and paraplates are all clearly developed and accord with the familar gonyaulacoid pattern. The spines arise only from parasutural crests; the overall areolation is on a much smaller scale and there are no processes on the paraplates themselves. Since the species has spine rows rather than parasutural crests, it is here placed into Lithodinia; however, the nature of the operculum - whether thrown off as a unit or as two or more opercular pieces - remains to be determined. For this reason, the generic reallocation heree proposed is only prrovisional. In its basic paratabulation pattern and overall areolation, Lithodinia? areolata resembles Meiourogonyaulax araneosa Muir and Sarjeant, 1978. However, the crest spines of the latter species are much lower and its ventral paratabulation appears dissimilar.