Archaeodictyomitra mitra Dumitrică,1997

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 : 138

Archaeodictyomitra mitra Dumitrică,1997

Figs. 13e, f

1973 Dictyomitra sp. , Foreman, pl. 10, fig. 7.

1981 Archaeodictyomitra sp. , Schaaf, pl. 4, fig. 1.

1981 Archaeodictyomitra vulgaris Pessagno – Schaaf, p. 447, pl. 4, fig. 2.

1981 Archaeodictyomitra brouweri var. a – Schaaf, p. 432, figs. 3a, b.

1982 Thanarla , various types – Okamura & Uto, pl. 1, figs. 16, 20-22, 24.

1988 Thanarla conica (Aliev) – Thurow, p. 406, pl. 6, fig. 20, non pl. 7, figs. 5, 1.

1994 Thanarla brouweri (Tan) – O’Dogherti, p. 86, pl. 5, figs. 4-6, 12.

1994 Thanarla pulchra (Squinabol) – O’Dogherty, p. 91, pl. 5, fig. 28.

1997 Archaeodictyomitra mitra Dumitrică in Dumitrică et al., p. 40, pl. 7, figs. 8, 13-15, 19-21, 23.

2009 Thanarla brouweri (Tan) – Ishii et. al., pl. 12, fig. 3. Studied material: Several illustrated specimens of which only two included on the plates.

Dimensions. Total length of shell of our specimens 130- 175 µm, length of ogival shell without distal neck 106- 138 µm, maximum diameter 83-93 µm.

Remarks. This species is characterized by an ogival shape and the sharp narrowing of the distal segment forming a kind of distal neck. This neck is just a thinner and narrower wall with intercostal pores. Although it has the same distal position on shell, it does not resemble the blade-like feet of the genus Thanarla Pessagno, 1977 . As noted before (Dumitrică et al., 1997), pores are either circular or slit-like, in the last case disposed obliquely or transversally. Structure of shell wall usually cavernous and surface sculptured similar to that of the A. massarii Dumitrică n. sp. (see discussion under this species). Such a structure is also visible on the specimens illustrated by Dumitrică in Dumitrică et al. (1997, pl. 7, figs. 15, 21).

Range. Valanginian to upper Hauterivian-lower Aptian according to Thurow (1988)

Figures

Fig. 13 a, b - Apiaromitra apiarium (Rüst): a - OZ836, b - OZ839, a1 - detail of ornamentation of last segment, b1 - detail of ornamentation of penultimate segment. c - Archaeodictyomitra robustovum Dumitrică n. sp., OZ837. d - Archaeodictyomitra sp., OZ839. e, f - Archaeodictyomitra mitra Dumitrică: e - OZ838, f - OZ824. g-k - Archaeodictyomitra massarii Dumitrică n. sp.: g - OZ834, g1 - detail of surface x1000. h - OZ834, i - OZ839, j - OZ834, k - OZ839; k1 - detail of wall showing the cavernous structure, k2 - detail of surface. l, p - Archaeodictyomitra longipora Dumitrică n. sp., OZ836; l - portion of surface of p much magnified showing the elevated intercostal area. m - Apiaromitra tyaughtonensis (Cordey), OZ837. n, t - Archaeodictyomitra dienii Dumitrică n. sp.: n - OZ836, t - OZ837. o - Thanarla cf. pulchra (Squinabol), OZ824. r - Archaeodictyomitra judae Dumitrica n. sp., OZ839. s - Archaeodictyomitra humerosa Dumitrică n. sp., OZ839. Figs. a, b x250, k1 and k2 x450, all the others x300.