Archaeodictyomitra inflata Dumitrică, 2022

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 : 135-136

Archaeodictyomitra inflata Dumitrică n. sp.

Figs. 12w, x

1997 Thanarla aff. brouweri (Tan) – Dumitrică et al., p. 43, pl. 8, figs. 7,?9.

1997 Thanarla pacifica Nakaseko & Nishimura – Dumitrică et al., p. 43, pl. 8, fig. 6, non 2, 4, 5.

Description. Shell small, bell-shaped with 9-10 costae on half the perimeter. Apical part, consisting probably only of cephalis and thorax, narrow conical, pointed. Rest of shell much inflated up to the middle or more, then slowly narrowing. Distal part with costae prolonged a little downward without forming lamellar feet. Pores circular or elongated, very small on the conical apical part, then increasing rapidly on the inflated part. Boundary between the two parts marked by a concavity in outline.

Studied material. Two specimens from Sardinia samples and one from Masirah Island sample I-215 .

Holotype. Figure 12x , OZ 834, coll. MGP-PD, stub PD120 -OZ834- R10-26 .

Paratype. Figure 12w , OZ839, coll. MGP-PD, stub PD120 - OZ839- R01-12 .

Dimensions. Length 123-140 µm, maximum diameter 100-128 µm.

Etymology. From the Latin inflatus , - a, - um = inflated.

Remarks. This species differs from other species of this genus by having an inflated body and from Archaeodictyomitra robustovum n. sp. (see below) by having the cephalothoracic conical segment narrower and separated from the rest of the body by a slight constriction.

Range and occurrence. Upper Valanginian of S’Ozzastru section.

Figures

Fig. 12 b - Crococapsa cf. horokanaiensis (Kawabata), OZ834. a, c, d - Crococapsa zweilii (Jud): a, OZ826; c, OZ836; d, OZ825. e-h - Crococapsa uterculus (Parona): e, f, h - OZ834, g - OZ825. i-o - Ocellicapsa ruthae Dumitrică n. sp.: i - OZ837, j - OZ837, k - OZ836, i - OZ834, m - OZ824, n - OZ838, n1 - detail of cephalothoracic body, arrow shows the place of very small pores at the boundary between the two parts of cephalic cavity, o - OZ825. p, r, t, v - Squinabolum elegans Dumitrică n. sp.: p - OZ824, r - OZ826, t - OZ836, s - Amphipyndax zyabrevi Dumitrică n. sp. - OZ825. u - Campanomitra pulchella (Rüst), OZ836. v - OZ834. w, x - Archaeodictyomitra inflata Dumitrică n. sp.: w - OZ839, x - OZ834. Figs. a, c-h, u x250, all the others x300.