Doliocapsa mediterranea 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 : 128-129

Doliocapsa mediterranea Dumitrică n. sp.

Fig. 11r

Description. Shell conical, smooth surfaced, without apical horn and consisting probably of four or five segments. Except for the collar boundary, marked by a few larger pores, boundaries between segments are difficult to identify being not marked outside by constrictions or other morphological or structural characters, except probably some circumferential rows of larger pores. Cephalis imperforated with rounded apex. Collar boundary marked by 3 or 4 pores visible on half the perimeter. Thorax and the following segments trapezoidal, constantly increasing in diameter up to the last but one segment, which is the widest. Last segment inverted trapezoidal, decreasing in diameter rapidly. Distal end open, with more or less regular border represented by the margin of the last circumferential row of pores. Pores distributed in circumferential rows, interrupted or irregular in some places.

Studied material. A single specimen in sample OZ834.

Holotype. Fig. 11r , coll. MGP-PD, stub PD120 -OZ834- R09-29 .

Dimensions. Length 143 µm, diameter of last chamber 87 µm.

Etymology. From its occurrence in the Mediterranean area.

Remarks. This species differs from the other congeneric taxa occurring in the Sardinian material by having a smooth-surfaced shell and segmentation not marked outside by constrictions.

Occurrence. A single specimen from the upper Valanginian of S’Ozzastru.

Figures

Fig. 11 a-b1 - Hiscocapsa grutterinki (Tan): a, OZ834, b, OZ839. c, c1, d, g - Hiscocapsa (?) ventriosa Dumitrică n. sp.: b, OZ839, c, OZ836, c1, aperture, g - complete specimen, V40, Svinița, Romania. e - Doliocapsa utoi Dumitrică n. sp., OZ824. f, f1, h, h1 - Hiscocapsa rugosacutis Dumitrică n. sp., OZ826. i-i1 - Hiscocapsa aitai Dumitrică n. sp., OZ824. p, s -Hiscocapsa lagunculoides Dumitrică n. sp., OZ834, OZ838; p1, s1- distal apertures of both specimens. j - Squinabollum cf. elegans Dumitrică n. sp., OZ826. k, k1 - Doliocapsa weisserti Dumitrică n. sp., OZ834. l - Hiscocapsa tuberculata Dumitrică n. sp., OZ826. m, m1, n - Doliocapsa erbae Dumitrică n. sp., OZ834. o – Doliocapsa favopora Dumitrică n. sp., OZ834. r - Doliocapsa mediterranea Dumitrică n. sp., OZ834. Figs. a-d, j x250; figs. c1, e, e1, f, f1, g, h, i, i1, k, k1, l, p, r x300, m-o, p1 x400.