Tritrabs ewingi (Pessagno, 1971)

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 : 108

Tritrabs ewingi (Pessagno, 1971)

Fig. 7e

1971? Paronaella ewingi Pessagno , p. 47, pl. 19, figs. 2- 5.

1980 Paronella (?) ewingi Pessagno – Holzer, p. 159, pl. 1, fig. 15, non 16 and 17 = Archaeotritrabs gracilis Steiger 1992 ).

1980 Tritrabs ewingi (Pessagno) – Baumgartner, p. 293, pl. 4, figs 5, 7, 17, 18.

1986 Tritrabs worzeli (Pessagno) – De Wever et al., pl. 8, fig. 9, not 8.

1984 Tritrabs ewingi (Pessagno) – Baumgartner, p. 791, pl. 10, fig. 10.

1994 Tritrabs ewingi (Pessagno – Jud, p. 116, pl. 23, figs. 12, 13.

1995 Tritrabs ewingi worzeli (Pessagno) – Baumgartner et al., p. 608, pl. 3115, figs. 1, 2, p. 609.

2017 Tritrabs ewingi (Pessagno) – Xu & Luo, figs. 3R, 3Z.

Studied material. A single fragment of an arm in PD120- OZ836-R07-07.

Remarks. The illustrated fragment and a few other small- er remains of arms are the only representative not only of this species but also of the whole family Tritrabidae in the upper Valanginian section from Sardinia. This species is extremely rare and difficult to separate from Tritrabs worzeli (Pessagno) when the ray tips are not very well preserved, as is the case of this specimen.

Range and occurrence. Late Bajocian to late Barremian or early Aptian.

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.