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Dinogymnium majus
From Fensome et al., 2019:
Dinogymnium majus Jain and Millepied, 1975, p.135–136, pl.1, figs.1–2. Holotype: Jain and Millepied, 1975, pl.1, fig.2. Age:
Campanian–Maastrichtian.
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Original description: [Jain and Millepied, 1975]:
Dinogymnium major sp. nov. (Pl. 1, Figs. 1-2).
Holotype - PI. 1, Fig. 2; Slide No. 8668a--12.
Type locality - Bore hole no. CM-4, depth 980 m; Senegal Basin, W. Africa.
Horizon - Campanian-Maestrichtian.
Diagnosis - Shell biconical, cingulumn prominent, dividing shell into two unequal halves, epitract much longer and wider than hypotract; apical and antapical ends rounded; longitudinal folds many, linear, regular, running in both epi-and hypotract from cingulum to poles, leaving short unfolded area at apex in epitract. Wall canals seen. Sulcus in hypotract present. Shell surface granulate. Archaeopyle apical.
Measurements
Shell length: holotype: 147 μm, range: 147-227 μm
Shell width: holotype: 91 μm, range: 60-120 μm
Cingulum Index: holotype: 60 μm, range: 56-66 μm
Comparison - Dinogymnium major sp. nov. compares best with the type species D. acuminatum Evitt et al. (1967) in having scabrate-granulate shell surface, similar apical and antapical ends and the presence of wall canals. But differs mainly in its much larger size and greater cingulum index which is much beyond the range of D. acuminatum.
Dinogymnium majus Jain and Millepied, 1975, p.135–136, pl.1, figs.1–2. Holotype: Jain and Millepied, 1975, pl.1, fig.2. Age:
Campanian–Maastrichtian.
---------------------------------------------------------------------------------------------------
Original description: [Jain and Millepied, 1975]:
Dinogymnium major sp. nov. (Pl. 1, Figs. 1-2).
Holotype - PI. 1, Fig. 2; Slide No. 8668a--12.
Type locality - Bore hole no. CM-4, depth 980 m; Senegal Basin, W. Africa.
Horizon - Campanian-Maestrichtian.
Diagnosis - Shell biconical, cingulumn prominent, dividing shell into two unequal halves, epitract much longer and wider than hypotract; apical and antapical ends rounded; longitudinal folds many, linear, regular, running in both epi-and hypotract from cingulum to poles, leaving short unfolded area at apex in epitract. Wall canals seen. Sulcus in hypotract present. Shell surface granulate. Archaeopyle apical.
Measurements
Shell length: holotype: 147 μm, range: 147-227 μm
Shell width: holotype: 91 μm, range: 60-120 μm
Cingulum Index: holotype: 60 μm, range: 56-66 μm
Comparison - Dinogymnium major sp. nov. compares best with the type species D. acuminatum Evitt et al. (1967) in having scabrate-granulate shell surface, similar apical and antapical ends and the presence of wall canals. But differs mainly in its much larger size and greater cingulum index which is much beyond the range of D. acuminatum.