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Lejeunecysta catoma
From Fensome et al., 2019:
Lejeunecysta catomus (Harland in Harland et al., 1991, p.651,653, figs.4d–e) Lentin and Williams, 1993, p.383. Holotype: Harland et al., 1991, fig.4d. Originally Protoperidinium subgenus Protoperidinium section Lejeunecysta (section name not validly published; Appendix B), subsequently (and now) Lejeunecysta. Contrary to the opinion of Lentin and Williams (1993, p.383), the name Protoperidinium catomus was validly published in Harland in Harland et al. (1991) since, although Lejeunecysta as a section name was not validly published, the species was assigned to the
validly published generic name Protoperidinium. NIA. Age: Early Pleistocene.
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Original description: [Harland et al., 1991]:
Protoperidinium (Protoperidinium sect. Lejeunecysta stat. nov.) catomum sp.nov.
Figure 4d, e
Derivation of name. Catomus, Latin (masc.), shoulder, with reference to the prominent shoulders exhibited by this species.
Description. Ovoidal to pentagonal, peridinioid cyst of autophragm. Wall smooth, light to dark brown with some thickening at the apex and antapex. Epicyst hemispheroidal with a prominent rounded apex and low to high, rounded shoulders that delineate the apical area. Hypocyst spheroidal, but not generally as large as the epicyst, with two antapical horns the left of which is usually the larger. The horns are variable
in morphology from being low, rounded to con- spicuously shouldered high rounded to acute cones. Parasulcus may be prominent and deeply incised or it may be broad and shallow. Paracingulum broad, up to one-third the cyst height, shallow and broad, entire and planar. Archeopyle enlarged standard hexa, probably formed by the loss of the 2a paraplate; an apical tongue may be present, operculum often in place or within the cyst.
Holotype. Figure 4d; arly Pleistocene, specimen MPK S599, at 65.33 m, BGS Ormesby Borehole.
Dimensions. Holotype: length 70 um, breadth 64 m.
Range: Length 64 (67.8) 71 um, sqrt(n-1) = 3.3; breadth 61 (64.3) 70 um, sqrt(n-1) = 4.0; n = 4.
Occurrence. This species is included in the Protoperidinium spp. count and occurs in units B to D; it has an effective last occurrence at 46.5 m.
Remarks. P. (P.) catomum is characterized by its consistently developed shoulders and broad paracingulum. Lejeunecysta cf. diversiforma (Bradford) Artzner and Dörhöfer, L. diversiforma muscatense (Bradford) Artzner and Dörhöfer as illustrated in Bradford & Wall (1984), and L. sp. cf., diversiforma (Bradford) Artzner and Dörhöfer figured by Powell (1986) may be of similar morphology and could be conspecific.
Lejeunecysta catomus (Harland in Harland et al., 1991, p.651,653, figs.4d–e) Lentin and Williams, 1993, p.383. Holotype: Harland et al., 1991, fig.4d. Originally Protoperidinium subgenus Protoperidinium section Lejeunecysta (section name not validly published; Appendix B), subsequently (and now) Lejeunecysta. Contrary to the opinion of Lentin and Williams (1993, p.383), the name Protoperidinium catomus was validly published in Harland in Harland et al. (1991) since, although Lejeunecysta as a section name was not validly published, the species was assigned to the
validly published generic name Protoperidinium. NIA. Age: Early Pleistocene.
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Original description: [Harland et al., 1991]:
Protoperidinium (Protoperidinium sect. Lejeunecysta stat. nov.) catomum sp.nov.
Figure 4d, e
Derivation of name. Catomus, Latin (masc.), shoulder, with reference to the prominent shoulders exhibited by this species.
Description. Ovoidal to pentagonal, peridinioid cyst of autophragm. Wall smooth, light to dark brown with some thickening at the apex and antapex. Epicyst hemispheroidal with a prominent rounded apex and low to high, rounded shoulders that delineate the apical area. Hypocyst spheroidal, but not generally as large as the epicyst, with two antapical horns the left of which is usually the larger. The horns are variable
in morphology from being low, rounded to con- spicuously shouldered high rounded to acute cones. Parasulcus may be prominent and deeply incised or it may be broad and shallow. Paracingulum broad, up to one-third the cyst height, shallow and broad, entire and planar. Archeopyle enlarged standard hexa, probably formed by the loss of the 2a paraplate; an apical tongue may be present, operculum often in place or within the cyst.
Holotype. Figure 4d; arly Pleistocene, specimen MPK S599, at 65.33 m, BGS Ormesby Borehole.
Dimensions. Holotype: length 70 um, breadth 64 m.
Range: Length 64 (67.8) 71 um, sqrt(n-1) = 3.3; breadth 61 (64.3) 70 um, sqrt(n-1) = 4.0; n = 4.
Occurrence. This species is included in the Protoperidinium spp. count and occurs in units B to D; it has an effective last occurrence at 46.5 m.
Remarks. P. (P.) catomum is characterized by its consistently developed shoulders and broad paracingulum. Lejeunecysta cf. diversiforma (Bradford) Artzner and Dörhöfer, L. diversiforma muscatense (Bradford) Artzner and Dörhöfer as illustrated in Bradford & Wall (1984), and L. sp. cf., diversiforma (Bradford) Artzner and Dörhöfer figured by Powell (1986) may be of similar morphology and could be conspecific.