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Pterodinium cingulatum ssp. intermedium
Pterodinium cingulatum ssp. intermedium (Cookson and Eisenack, 1974) Lentin and Williams, 1981
Originally Spiniferites cingulatus var. intermedius, subsequently Spiniferites cingulatus ssp. intermedius, thirdly Spiniferites? cingulatus ssp. intermedius, fourthly (and now) Pterodinium cingulatum ssp. intermedium.
Holotype: Cookson and Eisenack, 1974, pl.23, fig.8; lost according to Jan du Chêne et al., 1986
Age: Senonian
Original diagnosis: Cookson and Eisenack, 1974, p.64: Spiniferites cingulatus var. intermedius
A variant of the species Sp. cingulatus with oval, smooth shell with fairly high lists, distinct thickenings of the cutting edges and claw-like furcation-formations at their extremities.
Dimensions: about 66 x 60 µm.
Occurrence: Madura No. 1 bore, at 1018-1072 ft.
Remarks: Cookson and Eisenack, 1974, p.64: Spiniferites cingulatus var. intermedius
The specimen figured in Figure 9 is to be evaluated as transition form of var. cingulatus to var. intermedius. The cutting edges of the spanning-membranes only sporadically display furcation-prongs at the extremity and even there only by way of a suggestion. The specimen stems from the Gingin Brook bore, from the region between 404-414 ft.
A second specimen of same origin (Figure 11) likewise shows a slight resemblance to the var. intermedius, as the specimen figured in Figure 9. However, it is distinguished by a short, conical apical horn which, for lack of further similar specimens, has to be viewed as anomaly for the time being.
Originally Spiniferites cingulatus var. intermedius, subsequently Spiniferites cingulatus ssp. intermedius, thirdly Spiniferites? cingulatus ssp. intermedius, fourthly (and now) Pterodinium cingulatum ssp. intermedium.
Holotype: Cookson and Eisenack, 1974, pl.23, fig.8; lost according to Jan du Chêne et al., 1986
Age: Senonian
Original diagnosis: Cookson and Eisenack, 1974, p.64: Spiniferites cingulatus var. intermedius
A variant of the species Sp. cingulatus with oval, smooth shell with fairly high lists, distinct thickenings of the cutting edges and claw-like furcation-formations at their extremities.
Dimensions: about 66 x 60 µm.
Occurrence: Madura No. 1 bore, at 1018-1072 ft.
Remarks: Cookson and Eisenack, 1974, p.64: Spiniferites cingulatus var. intermedius
The specimen figured in Figure 9 is to be evaluated as transition form of var. cingulatus to var. intermedius. The cutting edges of the spanning-membranes only sporadically display furcation-prongs at the extremity and even there only by way of a suggestion. The specimen stems from the Gingin Brook bore, from the region between 404-414 ft.
A second specimen of same origin (Figure 11) likewise shows a slight resemblance to the var. intermedius, as the specimen figured in Figure 9. However, it is distinguished by a short, conical apical horn which, for lack of further similar specimens, has to be viewed as anomaly for the time being.