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Cobricosphaeridium spiniferum ssp. spiniferum
Cobricosphaeridium spiniferum ssp. spiniferum, Harland and Sarjeant, 1970
Autonym
Holotype: Harland and Sarjeant, 1970, pl.21, figs.3,6; text-fig.3
Locus typicus: Cobrico Swamp, Victoria, Australia
Stratum typicum: Holocene
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Original description: Harland and Sarjeant, 1970, p. 218-219
Diagnosis:
A Cobricosphaeridium having a sub-spherical central body bearing two types of processes. The first are long, approximately one-quarter of the cyst diameter, slender, tapering to cylindrical; they may be erect or curved, with their distal extremities evexate to digitate and foliate, occasionally forked. The base and shank of each process is ornamented with granules. The processes of the second type are short, approximately one-tenth of the cyst diameter, erect, cylindrical, slender and also may be forked at their tips.
Cingulum and sulcus are present, delineated by faint upraised sutures and alignment of processes; tabulation not otherwise determinable. Archaeopyle apical.
Description:
The spherical to sub-spherical central body is made up of two layers, the periphragm giving rise to all the ornamentation.
Total wall thickness of the order of 1 µm.
There are two distinct process types. The first is conspicuous, and less numerous than the second type; but even so, approximately thirty processes may be counted around the periphery of the holotype. They are very variable in morphology, and appear for the most part randomly disposed, although there is some alignment in the cingular and sulcal regions. It is not clear whether these are to be regarded as sutural or as intratabular processes. (No other indication of the tabulation is present.) These processes are solid and do not connect to the interior of the cyst. The processes of the second type are much smaller, less conspicuous, delicate, solid and having a hair-like appearance. They are very numerous, more than a hundred being seen around the periphery of the holotype. Seen in plan, they give the surface of the cyst a pseudogranular appearance.
Sulcus and cingulum are usually not well differentiated; some indication of their presence is given by the alignment of the larger processes and the presence of faint sutures. The amount of offset of the cingulum appears very slight.
The archaeopyle, not seen in the holotype, is apical and very similar to that of C. hebes, being angular with the same development of slits running out from the angles. No operculum was seen.
Dimensions:
Holotype: Length 49 µm, breadth 47 µm, the larger processes range from 4-9 µm in length and the small processes all measured 2 µm in length. Range: Length 36 (41.7) 49 µm, breadth 32 (37.2) 47 µm, length of larger processes 4 (7) 11 µm, smaller processes from 2 to 3 µm. Nine specimens were measured (the total available material).
Affinities:
This species was well represented in the assemblage and the preservation was always good. It differs from C. hebes in the entirely dissimilar nature of its processes.
Autonym
Holotype: Harland and Sarjeant, 1970, pl.21, figs.3,6; text-fig.3
Locus typicus: Cobrico Swamp, Victoria, Australia
Stratum typicum: Holocene
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Original description: Harland and Sarjeant, 1970, p. 218-219
Diagnosis:
A Cobricosphaeridium having a sub-spherical central body bearing two types of processes. The first are long, approximately one-quarter of the cyst diameter, slender, tapering to cylindrical; they may be erect or curved, with their distal extremities evexate to digitate and foliate, occasionally forked. The base and shank of each process is ornamented with granules. The processes of the second type are short, approximately one-tenth of the cyst diameter, erect, cylindrical, slender and also may be forked at their tips.
Cingulum and sulcus are present, delineated by faint upraised sutures and alignment of processes; tabulation not otherwise determinable. Archaeopyle apical.
Description:
The spherical to sub-spherical central body is made up of two layers, the periphragm giving rise to all the ornamentation.
Total wall thickness of the order of 1 µm.
There are two distinct process types. The first is conspicuous, and less numerous than the second type; but even so, approximately thirty processes may be counted around the periphery of the holotype. They are very variable in morphology, and appear for the most part randomly disposed, although there is some alignment in the cingular and sulcal regions. It is not clear whether these are to be regarded as sutural or as intratabular processes. (No other indication of the tabulation is present.) These processes are solid and do not connect to the interior of the cyst. The processes of the second type are much smaller, less conspicuous, delicate, solid and having a hair-like appearance. They are very numerous, more than a hundred being seen around the periphery of the holotype. Seen in plan, they give the surface of the cyst a pseudogranular appearance.
Sulcus and cingulum are usually not well differentiated; some indication of their presence is given by the alignment of the larger processes and the presence of faint sutures. The amount of offset of the cingulum appears very slight.
The archaeopyle, not seen in the holotype, is apical and very similar to that of C. hebes, being angular with the same development of slits running out from the angles. No operculum was seen.
Dimensions:
Holotype: Length 49 µm, breadth 47 µm, the larger processes range from 4-9 µm in length and the small processes all measured 2 µm in length. Range: Length 36 (41.7) 49 µm, breadth 32 (37.2) 47 µm, length of larger processes 4 (7) 11 µm, smaller processes from 2 to 3 µm. Nine specimens were measured (the total available material).
Affinities:
This species was well represented in the assemblage and the preservation was always good. It differs from C. hebes in the entirely dissimilar nature of its processes.