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Oligosphaeridium irregulare
Oligosphaeridium "irregulare" (Pocock, 1962, p.82, pl.15, figs.228–229) Davey and Williams, 1969, p.5.
Originally Hystrichosphaeridium, subsequently Oligosphaeridium.
Taxonomic senior synonym: Hystrichosphaeridium (as Oligosphaeridium) albertense, according to Jansonius (1986, p.213).
Taxonomic junior synonyms: Hystrichosphaeridium (as Oligosphaeridium?) coelenteratum, Hystrichosphaeridium (as Oligosphaeridium?) dispare, Hystrichosphaeridum (as Oligosphaeridium) reniforme, all according to Stover and Evitt (1978, p.69).
This combination, as a questionable assignment, was not validly published in Davey and Williams (1966b, p.77), since these authors did not fully reference the basionym. Fauconnier and Cornu in Fauconnier and Masure (2004, p.404) listed this as a problematic species but apparently accepted the synonymy cited above.
Holotype: Pocock, 1962, pl.15, figs.228–229, lost according to Jansonius (1986, p.220).
Lectotype: Jansonius, 1986, pl.4, fig.3, designated by Jansonius (1986, p.214 — caption to pl.4); Fauconnier and Masure, 2004, pl.55, fig.9.
Age: late Barremian–Aptian.
Original diagnosis: Pocock, 1962, p.82
Vesicle laevigate, thin, hyaline, circular in cross section; processes trumpet shaped, hollow, usually wide, very variable in shape; lips of processes wide and irregular, serrate with serration frequently extending far down the body of the processes in a completely irregular manner; lips frequently carry short spines.
Dimensions: Holotype: Diameter of vesicle 60 µm. Length of processes 22 µm. Basal diameter of processes 8 µm. Apical diameter of processes 18 µm.
Supplemental description: Brideaux, 1971, p.90
Cyst outline subcircular to ovoid in lateral view; wall thin, scabrate or smooth. Archeopyle apical, margin zig-zag. Processes highly variable in length and width, biconcave to tubular, hollow with flaring apices bearing long aculeate extensions or having highly dissected margins of variable shape.
Dimensions: Length of cyst body on 6 measured specimens, 40--66 µm; width, 37--50 µm. Length of processes, 14--30 µm, basal width,4--15 µm. Total of 10 specimens recovered.
Supplemental description: Below, 1982c, p. 24 (translated from German):
Note: The present material is very similar to the form depicted by SINGH (1971) on Plate 56, Fig. 6 as Oligosphaeridium sp.
Oligosphaeridium reniforme (TASCH, McCLURE & OFTEDAHL 1964) DAVEY (1969) is, in my opinion, synonymous with Oligosphaeridium irregulare.
Description: The scolochorate, spheroidal cyst consists of two smooth membranes. The appendages
reflect a tabulation typical of the genus Oligosphaeridium. The appendages of an individual
are almost equal in length. They reach approximately the radius of the central body. The shape of the processes is typical.
They are hollow, closed proximally, open distally, tubiform to biconic. From an expanded base, they taper towards the center to a minimal diameter and then widen again distally. The margin is irregularly slashed into spines and thorns of varying length, curved back toward the central body.
Originally Hystrichosphaeridium, subsequently Oligosphaeridium.
Taxonomic senior synonym: Hystrichosphaeridium (as Oligosphaeridium) albertense, according to Jansonius (1986, p.213).
Taxonomic junior synonyms: Hystrichosphaeridium (as Oligosphaeridium?) coelenteratum, Hystrichosphaeridium (as Oligosphaeridium?) dispare, Hystrichosphaeridum (as Oligosphaeridium) reniforme, all according to Stover and Evitt (1978, p.69).
This combination, as a questionable assignment, was not validly published in Davey and Williams (1966b, p.77), since these authors did not fully reference the basionym. Fauconnier and Cornu in Fauconnier and Masure (2004, p.404) listed this as a problematic species but apparently accepted the synonymy cited above.
Holotype: Pocock, 1962, pl.15, figs.228–229, lost according to Jansonius (1986, p.220).
Lectotype: Jansonius, 1986, pl.4, fig.3, designated by Jansonius (1986, p.214 — caption to pl.4); Fauconnier and Masure, 2004, pl.55, fig.9.
Age: late Barremian–Aptian.
Original diagnosis: Pocock, 1962, p.82
Vesicle laevigate, thin, hyaline, circular in cross section; processes trumpet shaped, hollow, usually wide, very variable in shape; lips of processes wide and irregular, serrate with serration frequently extending far down the body of the processes in a completely irregular manner; lips frequently carry short spines.
Dimensions: Holotype: Diameter of vesicle 60 µm. Length of processes 22 µm. Basal diameter of processes 8 µm. Apical diameter of processes 18 µm.
Supplemental description: Brideaux, 1971, p.90
Cyst outline subcircular to ovoid in lateral view; wall thin, scabrate or smooth. Archeopyle apical, margin zig-zag. Processes highly variable in length and width, biconcave to tubular, hollow with flaring apices bearing long aculeate extensions or having highly dissected margins of variable shape.
Dimensions: Length of cyst body on 6 measured specimens, 40--66 µm; width, 37--50 µm. Length of processes, 14--30 µm, basal width,4--15 µm. Total of 10 specimens recovered.
Supplemental description: Below, 1982c, p. 24 (translated from German):
Note: The present material is very similar to the form depicted by SINGH (1971) on Plate 56, Fig. 6 as Oligosphaeridium sp.
Oligosphaeridium reniforme (TASCH, McCLURE & OFTEDAHL 1964) DAVEY (1969) is, in my opinion, synonymous with Oligosphaeridium irregulare.
Description: The scolochorate, spheroidal cyst consists of two smooth membranes. The appendages
reflect a tabulation typical of the genus Oligosphaeridium. The appendages of an individual
are almost equal in length. They reach approximately the radius of the central body. The shape of the processes is typical.
They are hollow, closed proximally, open distally, tubiform to biconic. From an expanded base, they taper towards the center to a minimal diameter and then widen again distally. The margin is irregularly slashed into spines and thorns of varying length, curved back toward the central body.