Acratia, Delo, 1930

Forel, Marie-Béatrice, Crasquin, Sylvie, Hips, Kinga, Kershaw, Steve, Collin, Pierre-Yves & Haas, János, 2013, Biodiversity evolution through the Permian-Triassic boundary event: Ostracods from the Bükk Mountains, Hungary, Acta Palaeontologica Polonica 58 (1), pp. 195-219 : 204

Acratia ? jeanvannieri Forel sp. nov.

Figs. 9 , 10A–J .

Etymology: Dedicated to Dr. Jean Vannier (CNRS−Lyon 1 University, Lyon, France).

Type material: Holotype: one complete carapace, Fig. 10A , UPMC P6M2803 , sample 08BAN61 . Paratype: one complete carapace, Fig. 10B , UPMC P6M2804 , sample 08BAN63 .

Type locality: Bálvány North section, Bükk Mountains, Hungary .

Type horizon: Level 7, Gerennavár Limestone Formation , Griesbachian (Lower Triassic) .

Material.—139 complete and 12 broken carapaces, samples 08BAN52?, 54?, 56, 61, 62, 64, 65, 67, and 69 (see Fig. 2B), levels 3?, 4, 7, 8, Nagyvisnyó and Gerennavár Limestone Formations, Changhsingian to Griesbachian, Upper Permian– Lower Triassic.

Diagnosis.—A species of Acratia with a compact carapace, poorly slender extremities and a poorly expressed acratian beak. Dimensions.—L 163–708 µm; H 102–325 µm (101 mesured specimens; see Fig. 9 ).

Description.—Compact carapace; DB long, straight at RV, straight to gently convex at LV; ADB convex in LV, straight to gently concave at RV, AB with rather large radius of curvature for the genus, with maximum of curvature located around lower 1/3rd of H; acratian beak poorly expressed in RV, absent in LV; VB straight to gently convex at LV, gently concave at RV; PVB rectangular particularly at RV; LV overlaps RV all around the carapace with maximum at ADB and PDB; AB flattened laterally at some specimens; Hmax located behind 2/3rd of L. Internal features unknown.

Discussion.—The species displays a significant intraspecific variation with regard to the carapace outline. The very small forms show a broader AB and a higher H/L ratio compared to larger specimens. The doubt on generic attribution comes from the fact that the acratian beak is poorly expressed. The internal characters should be seen to be sure.

Acratia ? jeanvannieri sp. nov. is comparable to Acratia symmetrica Hao, 1992 from the Lower Triassic of Guizhou Province (South China; Hao 1992). The DB of A.? jeanvannieri sp. nov. is straighter, the extremities are not slender and the H/L ratio is higher ( A. symmetrica : 0.44, A.? jeanvannieri sp. nov.: 0.55).

Stratigraphic and geographic range.—Bálvány North section, levels 3? to 8, samples 08BAN52?, 54?, 56, 61, 62, 64, 65, 67, and 69 (see Fig. 2B), Nagyvisnyó and Gerennavár Limestone Formations, Changhsingian to Griesbachian, Upper Permian to Lower Triassic.

Figures

Fig. 9. Height/length diagram of Acratia? jeanvannieri Forel sp. nov.

Fig. 10. Ostracods from Bálvány North section, Bükk Mountains, Hungary. Right lateral views of complete carapaces. A–J. Acratia? jeanvannieri Forel sp. nov., Griesbachian, Lower Triassic. A. Holotype, UPMC P6M2803, sample 08BAN61. B. Paratype, UPMC P6M2804, sample 08BAN63. C. UPMC P6M2805, sample 08BAN63. D. UPMC P6M2806, sample 08BAN63. E. UPMC P6M2807, sample 08BAN61. F. UPMC P6M2808, sample 08BAN61. G. UPMC P6M2809, sample 08BAN63. H. UPMC P6M2810, sample 08BAN63. I. UPMC P6M2811, sample 08BAN62. J. UPMC P6M2812, sample 08BAN62. K–O. Acratia nagyvisnyoensis Forel sp. nov., Changhsingian, Upper Permian. K. Holotype, UPMC P6M2813, sample 08BAN47. L. Paratype, UPMC P6M2814, sample 08BAN47. M. UPMC P6M2815, sample 08BAN47. N. UPMC P6M2816, sample 08BAN47. O. UPMC P6M2817, sample 08BAN54. P, T. Acratia sp. A, Changhsingian, Upper Permian. P. UPMC P6M2818, sample 08BAN47. T. UPMC P6M2819, sample 08BAN47. Q. Acratia sp. B, Changhsingian, Upper Permian. UPMC P6M2820, sample 08BAN47. R, S. Acratia sp. C, Changhsingian, Upper Permian. R. UPMC P6M2821, sample 08BAN50. S. UPMC P6M2822, sample 08BAN52. Scale bars 100 µm.