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Parvocysta bjaerkei
Parvocysta bjaerkei Smelror, 1987, p.227,230, figs.4G,8C–D; text-fig.9. Emendation: Bailey and Hogg, 1995, p.58, as Fentonia bjaerkei.
NOW Limbicysta, an acritarch. Originally Parvocysta, subsequently Fentonia, thirdly (and now) Limbicysta
Holotype: Smelror, 1987, fig.4G
Age: Late Callovian
Type stratum and locality: Cape Flora. Northbrook Island.
Occurrence: Northbrook Island. Cape Flora. samples CF-7 and CF-3. Windy Gully. samples WG-1 and WG-2.
Original description (Smelror, 1987): Parvocysta bjaerkei sp. nov. Figs. 4G, 8C & D, Text-fig. 9 (see p. 237)
Description:
Dinoflagellate cysts basically subpentagonal in outline, with a more or less narrow paracingular region. A prominent apical horn and two precingular and two postcingular horn-like processes in lateral positions are present. Each of the lateral horns has a main branch and 3 to 5 finger-like branches, sometimes with bifurcate distal tips. The cyst wall is single layered, smooth, sometimes with scattered short spines in the apical and antapical areas. The archeopyle appears to be intercalary. but the exact outline is not known.
Dimensions:
Length including apical horn 38-54 µm. length of lateral processes 13-32 µm (15 specimens measured).
Remarks:
Parvocysta bjaerkei sp. nov. was first described under open nomenclature as Parvocysta sp. B from the Toarcian of Spitsbergen by Bjaerke (1980). Earlier. Bjaerke (1977) recorded this species as Sp. Indet. (PI. 10. Fig. 5) in his 'Association' D of Callovian age from Kong Karls Land. According to Haq et al. (1987. Fig.), representatives of the Parvocysta-complex became extinct within the Aalenian. while Woollam & Riding (1983) regard the Early Bajocian as the stratigraphic top of these species. However, Smelror (1988) reported Paruocysta bjaerkei sp. nov. in both Toarcian deposits and strata ranging from Late Bathonian to Early Oxfordian in Kong Karls Land. The consistent distribution of this species throughout the Early and Middle Callovian deposits on Kongsoya (Kong Karls Land) suggests that reworking is unlikely. In addition, this species also occurs in Lower Callovian dinoflagellate cyst assemblages from eastern England and within the Callovian offshore mid-Norway (pers. observation).
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Poulsen 1996, p. 85
Parvocysta bjaerkei Smelror 1987, Pl. 35, Figs. 9-10
Remarks: Danish specimens are slightly smaller (about 31 µm) than Toarcian specimens from Spitsbergen (about 43 µm) (Bjaeke, 1980).
Recorded occurrence: Denmark: Parvocysta nasuta Subzone, Mancodinium semitabulatum Zone.
NOW Limbicysta, an acritarch. Originally Parvocysta, subsequently Fentonia, thirdly (and now) Limbicysta
Holotype: Smelror, 1987, fig.4G
Age: Late Callovian
Type stratum and locality: Cape Flora. Northbrook Island.
Occurrence: Northbrook Island. Cape Flora. samples CF-7 and CF-3. Windy Gully. samples WG-1 and WG-2.
Original description (Smelror, 1987): Parvocysta bjaerkei sp. nov. Figs. 4G, 8C & D, Text-fig. 9 (see p. 237)
Description:
Dinoflagellate cysts basically subpentagonal in outline, with a more or less narrow paracingular region. A prominent apical horn and two precingular and two postcingular horn-like processes in lateral positions are present. Each of the lateral horns has a main branch and 3 to 5 finger-like branches, sometimes with bifurcate distal tips. The cyst wall is single layered, smooth, sometimes with scattered short spines in the apical and antapical areas. The archeopyle appears to be intercalary. but the exact outline is not known.
Dimensions:
Length including apical horn 38-54 µm. length of lateral processes 13-32 µm (15 specimens measured).
Remarks:
Parvocysta bjaerkei sp. nov. was first described under open nomenclature as Parvocysta sp. B from the Toarcian of Spitsbergen by Bjaerke (1980). Earlier. Bjaerke (1977) recorded this species as Sp. Indet. (PI. 10. Fig. 5) in his 'Association' D of Callovian age from Kong Karls Land. According to Haq et al. (1987. Fig.), representatives of the Parvocysta-complex became extinct within the Aalenian. while Woollam & Riding (1983) regard the Early Bajocian as the stratigraphic top of these species. However, Smelror (1988) reported Paruocysta bjaerkei sp. nov. in both Toarcian deposits and strata ranging from Late Bathonian to Early Oxfordian in Kong Karls Land. The consistent distribution of this species throughout the Early and Middle Callovian deposits on Kongsoya (Kong Karls Land) suggests that reworking is unlikely. In addition, this species also occurs in Lower Callovian dinoflagellate cyst assemblages from eastern England and within the Callovian offshore mid-Norway (pers. observation).
---------------------------
Poulsen 1996, p. 85
Parvocysta bjaerkei Smelror 1987, Pl. 35, Figs. 9-10
Remarks: Danish specimens are slightly smaller (about 31 µm) than Toarcian specimens from Spitsbergen (about 43 µm) (Bjaeke, 1980).
Recorded occurrence: Denmark: Parvocysta nasuta Subzone, Mancodinium semitabulatum Zone.