Bairdiacypris sp, Bradfield, 1935

Forel, Marie-Béatrice & Grădinaru, Eugen, 2020, Rhaetian (Late Triassic) ostracods (Crustacea, Ostracoda) from the offshore prolongation of the North Dobrogean Orogen into the Romanian Black Sea shelf, European Journal of Taxonomy 727, pp. 1-83 : 22

Bairdiacypris sp . in Forel et al. 2018

Fig. 6P

Bairdiacypris sp. – Forel et al. 2018: fig. 4/16.

Material examined

ROMANIA • 1 RV; Black Sea , Romanian Continental Shelf , borehole 817LV, sample CM31A; Rhaetian, Upper Triassic; MNHN.F. F63209 .

Dimensions

RV in Forel et al. (2018): L = 774 µm; H = 320 µm; H/L = 0.41.

RV in this paper: L = 766 µm; H = 331 µm; H/L = 0.43.

Occurrence

Killik Formation, Tavusçayiri Block, Sorgun Ophiolitic Mélange, southern Turkey, Huğlu Tuffite, Spongotortilispinus moixi radiolarian Zone, lower Tuvalian, Upper Carnian, Upper Triassic (Forel et al. 2018); Romanian Continental Shelf, Black Sea, Rhaetian, Upper Triassic (this paper).

Remarks

Bairdiacypris sp. in Forel et al. 2018 is related to Bairdiacypris anisica Kozur, 1971 from the Anisian, Middle Triassic, of Hungary ( Kozur 1971c). However, only one valve has been found here; since bairdiids are very homoplastic ostracods, it is most reasonable to avoid artificially extending the stratigraphic range of Bairdiacypris anisica Kozur, 1971 , from the Middle Triassic to the end of the Rhaetian, until more material is available to clarify this possibility. Bairdiacypris sp. in Forel et al. 2018 is also morphologically close to Bairdiacypris sp. in Forel et al. 2019 from the Carnian, Late Triassic, of the Kilek section in Turkey ( Forel et al. 2019a), but the anterior border is more raised in the present material. In the present analysis, Bairdiacypris sp. in Forel et al. 2018 is primarily related to Bairdiacypris sp. 1, from which it differs mainly by the morphology of the posterior extremity and the position of the oral concavity in front of H max, while it is at mid-L in Bairdiacypris sp. 1.

Figures

Fig. 6 (opposite page). SEM micrographs of ostracods from borehole 817 Lebăda Vest, drill core CM31, western portion of Black Sea shelf, Rhaetian, Late Triassic. All specimens are housed in the collections of the Muséum national d’histoire naturelle, Paris, France (MNHN). A. Bairdia sp. 8, same specimen as in Fig. 5U, dorsal view. B–C. Bairdia sp. 9. B. Right lateral view of a carapace, sample CM31C (MNHN.F.F63198). C. Same specimen, dorsal view. D–E. Bairdiacypris multidentata Bolz, 1971. D. Right lateral view of a carapace, sample CM31A (MNHN.F.F63199). E. Right lateral view of a carapace, sample CM31B (MNHN.F.F63200). F–O. Bairdiacypris argonautaii Forel sp. nov. F. Paratype 2, right lateral view of a carapace, sample CM31A (MNHN.F.F63201).G. Paratype 1, external view of a right valve, sample CM31B (MNHN.F.F63202). H. Right lateral view of a carapace, sample CM31A (MNHN.F.F63203). I. Right lateral view of a carapace, sample CM31A (MNHN.F.F63204). J. Right lateral view of a carapace, sample CM31B (MNHN.F.F63205). K. Same specimen, dorsal view. L. Right lateral view of a carapace, sample CM31A (MNHN.F.F63206). M. Right lateral view of a carapace, sample CM31A (MNHN.F.F63207). N. Same specimen, dorsal view. O. Right lateral view of a carapace, sample CM31A (MNHN.F.F63208). P. Bairdiacypris sp. in Forel et al. 2018, external view of a right valve, sample CM31A (MNHN.F.F63209). Q. Bairdiacypris sp. 1, external view of a right valve, sample CM31A (MNHN.F.F63210).R. Bairdiacypris sp. 2, external view of a right valve, sample CM31C (MNHN.F.F63211). S. Bairdiacypris sp. 3, external view of a right valve, sample CM31B (MNHN.F.F63212). T–U. Bairdiacypris? sp. 4. T. Right lateral view of a carapace, sample CM31B (MNHN.F.F63213). U. Right lateral view of a carapace, sample CM31A (MNHN.F.F63214). Scale bars: 100 µm.