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Spiniferites cornutus var. sinefurcatus
Spiniferites cornutus var. sinefurcatus Cookson and Eisenack, 1974
Originally Spiniferites cornutus var. sinefurcatus, subsequently Spiniferites cornutus ssp. sinefurcatus.
Taxonomic senior synonym (at subspecific rank): Spiniferites ramosus var. brevifurcatus (as Spiniferites ramosus subsp. brevifurcatus), according to Below (1982c, p.33).
Holotype: Cookson and Eisenack, 1974, pl.22, fig.8
Age: Albian-Cenomanian
Original diagnosis: Cookson and Eisenack, 1974, p.63
Shell oval, smooth, with highly helicoidal girdle and slanted longitudinal furrow. Processes missing. Spanning-membranes (lists) sturdily developed. They intersect one another there where in other species gonal processes arise. These cutting edges are there greatly drawn-out, terminate in an acute manner or form angular indentations and represent the processes. Accordingly furcation-prongs are not present. The apex bears a straight, stiff and pointed horn.
Dimensions: shell about 42 x 34 µm, overall about 69x52 µm, apical horn about 12 µm.
Occurrence: Balcatta No. 1 bore at 180-210 ft.
Remarks: Cookson and Eisenack, 1974, p.63
If one compares the Sp. crassifurcatus and the Sp. c. sinefurcatus, one is dealing with 2 extremes: var. crassifurcatus with sturdily developed furcated processes and var. sinefurcatus without such processes. Both variants possess well developed lists, which are broader in the var. sinefurcatus than in the var. crassifurcatus. .Intermediary members are not present at this time but are to be suspected, in similar manner as is the case when dealing with the Sp. cingulatus.
Originally Spiniferites cornutus var. sinefurcatus, subsequently Spiniferites cornutus ssp. sinefurcatus.
Taxonomic senior synonym (at subspecific rank): Spiniferites ramosus var. brevifurcatus (as Spiniferites ramosus subsp. brevifurcatus), according to Below (1982c, p.33).
Holotype: Cookson and Eisenack, 1974, pl.22, fig.8
Age: Albian-Cenomanian
Original diagnosis: Cookson and Eisenack, 1974, p.63
Shell oval, smooth, with highly helicoidal girdle and slanted longitudinal furrow. Processes missing. Spanning-membranes (lists) sturdily developed. They intersect one another there where in other species gonal processes arise. These cutting edges are there greatly drawn-out, terminate in an acute manner or form angular indentations and represent the processes. Accordingly furcation-prongs are not present. The apex bears a straight, stiff and pointed horn.
Dimensions: shell about 42 x 34 µm, overall about 69x52 µm, apical horn about 12 µm.
Occurrence: Balcatta No. 1 bore at 180-210 ft.
Remarks: Cookson and Eisenack, 1974, p.63
If one compares the Sp. crassifurcatus and the Sp. c. sinefurcatus, one is dealing with 2 extremes: var. crassifurcatus with sturdily developed furcated processes and var. sinefurcatus without such processes. Both variants possess well developed lists, which are broader in the var. sinefurcatus than in the var. crassifurcatus. .Intermediary members are not present at this time but are to be suspected, in similar manner as is the case when dealing with the Sp. cingulatus.