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Areosphaeridium pectiniforme
Areosphaeridium? pectiniforme, (Gerlach, 1961), Stover and Evitt, 1978; Emendation: Sarjeant, 1984
Originally Baltisphaeridium, subsequently Cleistosphaeridium, thirdly Areosphaeridium?.
Tax. sr. synonym of Areosphaeridium multicornutum Eaton, 1971, according to Sarjeant, 1984.
At the time of the transfer, Stover and Evitt, 1978, considered this to be a provisionally accepted species.
Holotype: Gerlach, 1961, pl. 28, fig.14; Sarjeant, 1984, pl.1, fig.2; pl.4, fig.2
Paratype: Gerlach, 1961
Locus typicus: Well Emsbüren, NW Germany
Stratum typicum: Oligocene
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Original description as Baltisphaeridium pectiniforme: [Gerlach, 1961, p. 195-196]: (Translation: LPP)
Diagnosis:
A species of the genus Baltisphaeridium with slender, solid processes, which extend widely and are set with numerous small hooks. Shell circular to oval. Membrane granulate.
Description:
The outline of the theca changes between circular and oval. The processes are massive, slender and extend to both sides. The rims of these side-branches are set with small hooks, so that the processes show a similarity with a rake. The membrane is delicate, hyaline and finely granulate.
Dimensions:
holotype: 32 (13) µm; paratypes: 42 (21) µm.
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Emended description:
Sarjeant, 1984, p. 83-84, 86:
Description:
Proximate, skolochorate cysts, intratabulate and acavate. Central body subspherical to subovoidal or subpolygonal; phragma thin, two layered.
Processes ranging in length between about 35% to 45% of the cyst breadth. Each process is distally expanded and bifurcate (licrate); the attitude of the bifurcations ranges from patulate to recurved. The two branches are of variable relative and absolute length; they vary in breadth from slender, with a denticulate distal margin, to broad, with a denticulate or irregular distal margin and with some development of fenestration. Paratabulation 4", 6"", 7c, 6""", 1p, 5pa, 1"""". The paraplates, however, are not always fully represented; the processes equivalent to 6"" and 1p, and up to three of the cingular processes, may be lacking and the preantapical processes are often very incompletely developed (as few as one may be present in some specimens). The antapex, with its single process, is typically offset to the right of the midventral line.
Surface of phragma laevigate to finely or more coarsely granulate.
Archaeopyle apical (type tA): operculum (or opercular pieces?) free.
Originally Baltisphaeridium, subsequently Cleistosphaeridium, thirdly Areosphaeridium?.
Tax. sr. synonym of Areosphaeridium multicornutum Eaton, 1971, according to Sarjeant, 1984.
At the time of the transfer, Stover and Evitt, 1978, considered this to be a provisionally accepted species.
Holotype: Gerlach, 1961, pl. 28, fig.14; Sarjeant, 1984, pl.1, fig.2; pl.4, fig.2
Paratype: Gerlach, 1961
Locus typicus: Well Emsbüren, NW Germany
Stratum typicum: Oligocene
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Original description as Baltisphaeridium pectiniforme: [Gerlach, 1961, p. 195-196]: (Translation: LPP)
Diagnosis:
A species of the genus Baltisphaeridium with slender, solid processes, which extend widely and are set with numerous small hooks. Shell circular to oval. Membrane granulate.
Description:
The outline of the theca changes between circular and oval. The processes are massive, slender and extend to both sides. The rims of these side-branches are set with small hooks, so that the processes show a similarity with a rake. The membrane is delicate, hyaline and finely granulate.
Dimensions:
holotype: 32 (13) µm; paratypes: 42 (21) µm.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended description:
Sarjeant, 1984, p. 83-84, 86:
Description:
Proximate, skolochorate cysts, intratabulate and acavate. Central body subspherical to subovoidal or subpolygonal; phragma thin, two layered.
Processes ranging in length between about 35% to 45% of the cyst breadth. Each process is distally expanded and bifurcate (licrate); the attitude of the bifurcations ranges from patulate to recurved. The two branches are of variable relative and absolute length; they vary in breadth from slender, with a denticulate distal margin, to broad, with a denticulate or irregular distal margin and with some development of fenestration. Paratabulation 4", 6"", 7c, 6""", 1p, 5pa, 1"""". The paraplates, however, are not always fully represented; the processes equivalent to 6"" and 1p, and up to three of the cingular processes, may be lacking and the preantapical processes are often very incompletely developed (as few as one may be present in some specimens). The antapex, with its single process, is typically offset to the right of the midventral line.
Surface of phragma laevigate to finely or more coarsely granulate.
Archaeopyle apical (type tA): operculum (or opercular pieces?) free.