Tyrrhenocythere aff. ruggierii ( Devoto, 1967 )

RAUSCH, LEA, STOICA, MARIUS & LAZAREV, SERGEI, 2020, A Late Miocene - Early Pliocene Paratethyan Type Ostracod Fauna From The Denizli Basin (Sw Anatolia) And Its Palaeogeographic Implications, Acta Palaeontologica Romaniae 16 (2), pp. 3-56 : 27-29

Tyrrhenocythere aff. ruggierii ( Devoto, 1967)

Fig. 17 k-l

1967 Tyrrhenocythere ruggierii - Devoto, p. 31-35, figs. 5-8.

1982 Tyrrhenocythere ruggierii Devoto- Olteanu, p. 54, pl. 1, figs. 1–6.

1999 Tyrrhenocythere ruggierii Devoto- Gliozzi, p. 202, pl. III, fig. a-c.

2016 Tyrrhenocythere cf. ruggierii Devoto- Stoica et al., p. 862, pl. 3, 5-9.

Description. The carapace is heavily calcified and shows an oblong-oval outline. The anterior margin is broadly rounded and has its highest point at the anterodorsal corner. The dorsal margin is inclined backwards and continues smoothly onto both the anterior-and the posterior end. The ventral margin shows a slight convexity with a distinct concavity close to its anterior end. The posterior end has a weakly pronounced shoulder that starts midheight and is rounded in its lower part. Above the shoulder the posterior margin is slightly concave. The eye spot is well developed and positioned at the anterior end of the dorsal margin on the otherwise almost smooth surface of the valve. Only close to the posterior-and the anterior end medium-sized longitudinally running meshes and small sized cells and pits are occurring. There is a transversal rim that has its maximum development along the postero-and anteroventral area. Branching pore channels within the broad marginal zone are present. The muscle scar pattern and the hinge structure are genus typical. Dimension: L = 1,09 – 1,10 mm, H = 0,43 – 0,64 –mm, the minimum sizes include juveniles too.

Remarks. Krstić (1977) is assuming that T. ruggierii is probably a synonymous with T. truncata (Schneider) that has been described in a variety of Paratethyan Basins. Carbonnel (1978) and Olteanu (1982) are not agreeing with the hypothesis of Krstić and consider it a valid species. On the other hand, Krstić (in Krstić and Stancheva, 1990) described Tyrrhenocythere triebeli , from the Novorossian of North Greece, Strimon basin that has many similarities with T. ruggieri . A morphological similar looking species was described by Olteanu (1982) as Tyrrhenocythere dacicum from Pontian sediments of the Dacian Basin.

Chronostratigraphical and geographical distribution. This species is not mentioned often in the Paratethys domain and has only been described by Olteanu (1982) from the middle-and late Pontian of the Dacian Basin. Outside the Paratethys the species has been reported from the Spanish Lago-Mare ( Stoica et al., 2016), the late Messinian deposits of the Vera Basin from Spain ( Carbonnel, 1978) and the late Messinian of the Vicenne Basin in Italy ( Gliozzi, 1999).

Ecology. The ecology resembles the preferences of Tyrrhenocythere pontica .

Figures

Fig. 17a-e Tyrrhenocythere pontica; a LV, external view, ♂; b RV, external view, ♀; c LV, external view, ♀; d LV, external view, A2 juvenile; e LV, external view, A3 juvenile; f-j Tyrrhenocythere aff. pontica; f LV, external view, ♂; g LV, external view, ♀; h LV, external view, A1 juvenile; i RV, external view, A2 juvenile; j LV, external view, A3 juvenile; k, l Tyrrhenocythere aff. ruggierii; k LV, external view, ♀; l RV, external view, ♀; (specimens a-e from section B, samples 36,6 m – 61,5 m; specimens f-j from section A, sample 15 m; specimens k-l from section B, sample 65 m).