Spiroclypeus aff. carpaticus ( Uhlig, 1886 )

Less, György & Özcan, Ercan, 2008, The late Eocene evolution of nummulitid foraminifer Spiroclypeus in the Western Tethys, Acta Palaeontologica Polonica 53 (2), pp. 303-316 : 313

Spiroclypeus aff. carpaticus ( Uhlig, 1886)

Fig. 7O.

The few specimens found in the sample from Biarritz, Lou Cachaou have intermediate numerical characteristics between those of Spiroclypeus sirottii and S. carpaticus (see Table 1 and Figs. 4–6 ). Because of the scarcity of the material the axial section could not be investigated. Based on the associated Heterostegina gracilis marking the late Priabonian and according to the average number of undivided chambers (Xmean = 2.38) that is closer to the value defining S. carpaticus than to that of S. sirottii , the population from Biarritz is determined as S. aff. carpaticus , taking into account also the relatively small size of the proloculus.

Figures

Fig. 4. Distribution of spiroclypeid populations (mean values at the 95.44% confidence level) on the S–X (heterosteginid escalation versus operculinid reduction) bivariate plot (both scales are logarithmic).

Fig. 5. Distribution of spiroclypeid populations (mean values at the 95.44% confidence level) on the P–X (proloculus diameter versus operculinid reduction) bivariate plot (X is on logarithmic scale).

Fig. 6. Distribution of spiroclypeid populations (mean values at the 95.44% confidence level) on the D–X (second whorl diameter versus operculinid reduction) bivariate plot (X is on logarithmic scale).