Bairdia davehornei Forel, 2013

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 : 203

Bairdia davehornei Forel sp. nov.

Figs. 6Q–U , 8 .

Etymology: Dedicated to Professor David J. Horne (Queen Mary University, London).

Type material: Holotype: one complete carapace, Fig. 6Q , UPMC P6M2777 , sample 08BAN61 . Paratype: one complete carapace, Fig. 6R , UPMC P6M2778 , sample 08BAN62 .

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

Type horizon: Level 7, Gerennavár Limestone Formation , Changhsingian, Upper Permian .

Material.—32 complete and 2 broken carapaces, samples 08BAN47, 61 and 62 (see Fig. 2B), levels 1, 7, 8, Nagyvisnyó and Gerennavár Limestone Formations, Bálvány North section, Hungary, Changhsingian to Griesbachian, Upper Permian–Lower Triassic.

Diagnosis.—A species of Bairdia with an elongated carapace (L/H = 2) with a truncated AVB, regularly arched dorsal parts, and a rounded PB with the maximum of curvature at lower 1/3rd of H. Dimensions.—L 290–560 µm; H 141–275 µm (see Fig. 8 ).

Description.—Carapace elongated (L = 2H), DB, PDB, and ADB regularly arched at LV; DB, PDB, and ADB quite straight at RV; AB with small radius of curvature, with maximum of curvature located above mid−H; AVB truncated; VB concave, particularly at RV; PB rounded with large radius of curvature, maximum of curvature located at the lower 1/3 of H; typical bairdian beak visible only on some specimens; LV overlaps RV slightly all around the carapace with maximum at DB; Hmax located near mid−L. Internal features unknown. Discussion.— Bairdia davehornei sp. nov. could be compared to Bairdia fangnianqiaoi Crasquin, 2010 from the Griesbachian Meishan section ( China; Crasquin et al. 2010a). The latter species has a more slender PB and a more elongated carapace in lateral view. Cryptobairdia heshanenis Chen, 2002 (Wuchiapingian of Matan and Pinding section, China; Shi and Chen 2002) is also close to Bairdia davehornei sp. nov. but has a more distinct flattened and a larger AB. Bairdia davehornei sp. nov. differs from Bairdia ? kemerensis from the Griesbachian of Turkey (Crasquin−Soleau et al. 2004b) in its shorter DB and smaller AB.

Stratigraphic and geographic range.—Bálvány North section, levels 1 to 8, samples 08BAN47, 61 and 62 (see Fig. 2B), Nagyvisnyó and Gerennavár Limestone Formations, Changhsingian–Griesbachian, Upper Permian–Lower Triassic.

Figures

Fig. 6. Ostracods from Bálvány North section, Hungary (except A–D from Bulla section, Northern Italy). Right (A, E, G–W) and left (B, C, D, F) lateral views of complete carapaces. A–G. Langdaia bullabalvanyensis Crasquin sp. nov., Griesbachian, Lower Triassic. A. Holotype, UPMC P6M2762, sample 05BU19. B. Paratype, UPMC P6M2763, sample 05BU19. C. UPMC P6M2232, sample 05BU19. D. UPMC P6M2764, sample 05BU19. E. UPMC P6M2765, sample 08BAN67. F. UPMC P6M2766, sample 08BAN67. G. UPMC P6M2767, sample 08BAN67. H, I. Bairdia baudini nom. nov. H. UPMC P6M2785, sample 08BAN48, Changhsingian, Upper Permian. I. UPMC P6M2786, sample 08BAN61, Griesbachian, Lower Triassic. J–M. Bairdia wailiensis Crasquin−Soleau, 2006, Griesbachian, Lower Triassic. J. UPMC P6M2770, sample 08BAN62. K. UPMC P6M2771, sample 08BAN47. L. UPMC P6M2772, sample 08BAN62. M. UPMC P6M2773, sample 08BAN62. N–P. Bairdia anisongae Forel sp. nov. N. Holotype, UPMC P6M2774, sample 08BAN55, Changhsingian, Upper Permian. O. Paratype, UPMC P6M2775, sample 08BAN62, Grisbachian, Lower Triassic. P. UPMC P6M2776, sample 08BAN47, Changhsingian, Upper Permian. Q–U. Bairdia davehornei Forel sp. nov., Griesbachian, Lower Triassic. Q. Holotype, UPMC P6M2777, sample 08BAN61. R. Paratype, UPMC P6M2778, sample 08BAN62. S. UPMC P6M2779, sample 08BAN62. T. UPMC P6M2780, sample 08BAN62. U. UPMC P6M2781, sample 08BAN62. V, W. Bairdia cf. Bairdia davehornei Forel sp. nov., Griesbachian, Lower Triassic. V. UPMC P6M2782, sample 08BAN62. W. UPMC P6M2783, sample 08BAN61. Scale bars 100 µm.

Fig. 8. Height/length diagram of Bairdia davehornei Forel sp. nov.