Paleodictyoconus Moullade, 1965

SCHLAGINTWEIT, FELIX, 2021, Agglutinated Conical Foraminifera (Orbitolinidae, Coskinolinidae) From The Upper Cretaceous (Campanian) Of Greece, With Description Of Paracoskinolina Klokovaensis N. Sp., Acta Palaeontologica Romaniae 17 (2), pp. 83-94 : 85-86

Genus Paleodictyoconus Moullade, 1965 Paleodictyoconus cf. senonicus Moullade & Viallard, 1973

Figs. 3 pars, 4b-c, e-f

1970 Dictyoconus sp. – Fleury, pl. 1, 1?, 4.

*1973 Paleodictyoconus senonicus n. sp. – Moullade and Viallard, p. 338-340, pls. 1-3.

?1976 Paleodictyoconus sp. – Luperto Sinni, p. 315-316, pl. 39, figs. 1-6, pl. 40, figs. 1-4.

1985 Paleodictyoconus senonicus Moullade & Viallard – Bilotte, p. 358, pl. 16, figs. 1-5.

Felix Schlagintweit

Remarks: Although Moullade and Viallard (1973, p. 340, footnote) noted similarities of the specimens illustrated by Fleury (1970) as Dictyoconus sp. with Paleodictyoconus senonicus , they refrained from a concluding assessment because the Greece material lacks axial sections showing the pronounced initial spire, a circumstance also accounting for some reservations expressed herein (cf.). P. cf. senonicus has been observed in association with P. klokovaensis in the same samples ( Fig. 3 ). The dimensions of P. senonicus are larger (height up to 1.5 mm, diameter up to 1.15 mm), there are 1 to 2 rafters (according to Moullade and Viallard, 1973), the test diameter is not increasing continuously from apex to base as in P. klokovaensis , but may decrease later resulting in a bell-shaped outline in axial sections (e.g. Moullade and Viallard, 1973, pl. 1, figs. 1, 5, 8). The pillars of P. senonicus , with a tendency to anastomization, are alternating between subsequent chambers ( Fig. 4C, F ). Last but not least, there are 8-9 chambers per last 0.5 mm axial length, meaning that the chamber height of P. cf. senonicus is reduced compared to P. klokovaensis .

Remarks: Bilotte (1985) reported P. senonicus from the lower Campanian of the French Pyrenees. For the orbitolinid occurrences in southern Italy, the exact stratigraphic position is still uncertain ( Luperto Sinni, 1976, p. 303, “restano…datati con molta precision”). At the type-locality, P. senonicus occurs in levels with Lacazina elongata Munier-Chalmas & Schlumberger below and above. This species is reported from the upper Santonian– lower Campanian ( Gräfe, 2005, fig. 4).

Figures

Fig. 3 Upper Cretaceous (middle Campanian) microfacies of sample GKL 39. Pa = Paracoskinolina klokovaensis n. sp., Pal = Paleodictyoconus senonicus Moullade & Viallard, Di = Dicyclina schlumbergeri Munier-Chalmas.

Fig. 4 Coskinolinidae (a, d, g, j) and Orbitolinidae (b-c, e-f, h-i, k-l) from the Campanian of Klokova Mountain SW Greece (a-f, h-l) and Brač Island, Croatia (g). Lepinoconus chiocchinii Cruz-Abad et al. a Oblique section. d Broken transverse section. g, j Subaxial sections. Paleodictyoconus senonicus Moullade & Viallard b, e Oblique transverse sections. c, f Subaxial sections. Calvezicionus lecalvezae Caus & Cornella. h, k Oblique sections. i Oblique section passing the biloculine, slightly inclined megalospheric embryo. Dictyoconella complanata Henson. l Oblique section in the plane of compression. Abbreviations: b = beam, de = deuteroconch, f = foramen, p = protoconch, pi = pillar, s = septum. Thin sections: GKL 43 (a, j, i, l), GKL 43x (d, k), GKL 39 (b-c, e, h), GKL 39x (f).