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Exochosphaeridium bifidum ssp. bifidum
Exochospaeridium bifidum ssp. bifidum; Emendation: Marheinecke, 1992, p.51, as Exochosphaeridium bifidum subsp. bifidum
Autonym. Now redundant.
Holotype: Clarke and Verdier, 1967, pl. 17, fig. 5
Paratype: Clarke and Verdier, 1967
Locus typicus: Culver Cliff, Isle of Wight, S England
Stratum typicum: Cenomanian-Campanian
Translation Marheinecke, 1992: LPP
Original description: Clarke and Verdier, 1967, p. 72-73: Baltisphaeridium bifidum
Diagnosis: A species of Baltisphaeridium diagnosed by the thick wall and long processes which have slightly bifid or expanded tops. The base of the processes and the body generally exhibit a striate appearance.
Description (annotated): Main body circular, wall 2-3 Ám thick, bearing long distinct processes. Processes generally discrete, only occasionally being joined at their bases. Each process widens at its base and possesses a short bifurcation or expansion distally. The sculpture of the body, which extends in some cases onto the base of the processes, consists of elongated perforations which imparts a striate appearance to the wall and especially to the proximal part of the processes. An apical opening is present on some specimens.
Dimensions: Holotype: diameter of body, 66 Ám, length of processes, 22 Ám. Range: diameter of body, 44-72 Ám, length of processes, 13-34 Ám.
Clarke et al., 1968, p. 182
Baltisphaeridium bifidum Clarke and Verdier, 1967 is now considered to have a precingular archaeopyle. Its transfer to Exochosphaeridium Davey et al., 1966, as Exochosphaeridium bifidum is therefore proposed.
Emended description: Marheinecke, 1992, p.51
Cyst sphaeroidal to subsphaeroidal. Wall thick, composed of pedium and spongious luxuria, developing a net-like tegillum. Luxuria forms c. 60-80 thin, solid processes. Base of processes broadened and striate, distal ends usually bifurcate or multifurcate. Processes intraareate, three to four processes per area. Cingulum marked by a row of processes, seldom connected by a weak ridge. Sulcal processes in generall thinner, but not always distinguishable. Apical process larger and branched. Antapical process consists of two fused processes. Archeopyle precingular 3"", operculum secate.
Affinities:
Clarke and Verdier, 1969, p. 73: Baltisphaeridium bifidum
It is evident that B. bifidum sp. nov. must be compared with B. striolatum (Defl. 1937) Downie and Sarjeant 1963. From an examination of the holotype of B. striolatum it is concluded that B. bifidum differs from it in the more constant form of the processes, the presence of bifid or expanded tops, and the absence of low sutures connecting the bases of processes.
Autonym. Now redundant.
Holotype: Clarke and Verdier, 1967, pl. 17, fig. 5
Paratype: Clarke and Verdier, 1967
Locus typicus: Culver Cliff, Isle of Wight, S England
Stratum typicum: Cenomanian-Campanian
Translation Marheinecke, 1992: LPP
Original description: Clarke and Verdier, 1967, p. 72-73: Baltisphaeridium bifidum
Diagnosis: A species of Baltisphaeridium diagnosed by the thick wall and long processes which have slightly bifid or expanded tops. The base of the processes and the body generally exhibit a striate appearance.
Description (annotated): Main body circular, wall 2-3 Ám thick, bearing long distinct processes. Processes generally discrete, only occasionally being joined at their bases. Each process widens at its base and possesses a short bifurcation or expansion distally. The sculpture of the body, which extends in some cases onto the base of the processes, consists of elongated perforations which imparts a striate appearance to the wall and especially to the proximal part of the processes. An apical opening is present on some specimens.
Dimensions: Holotype: diameter of body, 66 Ám, length of processes, 22 Ám. Range: diameter of body, 44-72 Ám, length of processes, 13-34 Ám.
Clarke et al., 1968, p. 182
Baltisphaeridium bifidum Clarke and Verdier, 1967 is now considered to have a precingular archaeopyle. Its transfer to Exochosphaeridium Davey et al., 1966, as Exochosphaeridium bifidum is therefore proposed.
Emended description: Marheinecke, 1992, p.51
Cyst sphaeroidal to subsphaeroidal. Wall thick, composed of pedium and spongious luxuria, developing a net-like tegillum. Luxuria forms c. 60-80 thin, solid processes. Base of processes broadened and striate, distal ends usually bifurcate or multifurcate. Processes intraareate, three to four processes per area. Cingulum marked by a row of processes, seldom connected by a weak ridge. Sulcal processes in generall thinner, but not always distinguishable. Apical process larger and branched. Antapical process consists of two fused processes. Archeopyle precingular 3"", operculum secate.
Affinities:
Clarke and Verdier, 1969, p. 73: Baltisphaeridium bifidum
It is evident that B. bifidum sp. nov. must be compared with B. striolatum (Defl. 1937) Downie and Sarjeant 1963. From an examination of the holotype of B. striolatum it is concluded that B. bifidum differs from it in the more constant form of the processes, the presence of bifid or expanded tops, and the absence of low sutures connecting the bases of processes.