Pantanellium sp. 2

Dumitrica, Paulian, Dieni, Iginio & Massari, Francesco, 2022, Valanginian Radiolarians Of Ne Sardinia (Italy) In The Frame Of The Weissert Event, Acta Palaeontologica Romaniae 18 (2), pp. 97-159 : 109

Pantanellium sp. 2

Fig. 7k

Remarks. This specimen differs from the other specimens herein illustrated in having a smooth surface, no nodes at frame vertices, a smaller wall thickness, a slightly ellipsoidal shell, and spines with rather thin blades. Also, pore frames are slightly thickened on the external border of shell and the centre of the vertices of the pore frames are depressed, forming small cavities. Inner surface of pores contains also remains of a spongy framework, but they are less common and irregularly disposed. Although the spines are broken off, one can see that their blades are thin and their length does not seem to be bigger than the length of the spines of the other species occurring in this assemblage.

Dimensions. Diameter 86 µm, length 100 µm.

Occurrence: A single specimen in the sample OZ834.

Figures

Fig. 7 a - Praeconosphaera sphaeroconus (Rüst OZ826. b-d - Praeconosphaera antiqua (Parona): b - OZ834, c - OZ838, d - OZ825. e - Tritrabs ewingi (Pessagno), arm in lateral view, OZ836. f-h - Emiluvia chica Foreman, OZ836; f - face view, g - lateral view from a spine, h - lateral view of a broken specimen showing the medullary test. i - Pantanellium sp. 1, OZ825. j, l-n1 - Pantanellium squinabolli (Tan): j - OZ834; l, m - OZ834, n - OZ836; m1, n1, details of inner wall of pores. k - Pantanellium sp. 2, OZ834. o – Pantanellium cf. squinaboli (Tan), OZ836; p - Praeconocaryomma copiosa Wu, OZ836. r - Praeconocaryomma thurowi Dumitrică n. sp., OZ836. s, t - Triactoma tithonianum Rüst, side views; s - OZ834, broken off specimen showing medullary shell; t - OZ825, equatorial view, t1 – face view; s1, t2 - detail of the base of spines of figs. s and t, respectively, x800. Figs. a-h, l-n x200; i-k, o-r x300; s, t x400, m1, n1 x500.