Bairdia sp. A

Tarnac, Anaëlle, Forel, Marie-Béatrice, Nestell, Galina, Nestell, Merlynd & Crasquin, Sylvie, 2021, Middle Permian ostracods (Crustacea) from the Guadalupe Mountains, West Texas, USA, European Journal of Taxonomy 770, pp. 1-60 : 30-32

Bairdia sp. A

Fig. 8D

Material examined

USA • 1 complete carapace; Guadalupe Mountains , Williams Ranch Member , Cutoff Formation , Quarry section, sample GM1; Roadian, Middle Permian; MNHN.F. F63422 • 1 complete carapace, 4 valves; same locality as for preceding; Roadian , Guadalupian, Middle Permian; MNHN.F. F63492 .

Fig. 8 (next page). SEM micrographs of ostracods from the Middle Permian (Roadian, Quarry section, samples GM1 and GM4; Capitanian, MKCS 1 section, samples 4 (GM5) and 2 (GM6)) of the Guadalupe Mountains (West Texas, USA). All specimens are temporarily housed in the collections of the Muséum national d’histoire naturelle, Paris, France ( MNHN). A–B. Bairdia elcapitanensis Forel sp. nov. A. External view of a right valve, sample GM1 ( MNHN.F. F63419 ). B. Holotype, external view of a right valve, sample GM1 ( MNHN.F. F63420 ). – C. Bairdia cf. postacuta Chen, 1958, right lateral view of a carapace, sample GM1 ( MNHN.F. F63421 ). – D. Bairdia sp. A , right lateral view of a carapace, sample GM1 ( MNHN.F. F63422 ). – E. Bairdia sp. B , right lateral view of a carapace, sample GM1 ( MNHN.F. F63423 ). – F. Bairdia sp. C , right lateral view of a carapace, sample GM1 ( MNHN.F. F63424 ) – G. Bairdiacypris sp. B , right lateral view of a carapace, sample 2 (GM6) ( MNHN.F. F63425 ). – H. Bairdiacypris sp. C , right lateral view of a carapace, sample GM1 ( MNHN.F. F63426 ). – I–J. Fabalicypris acetalata ( Coryell & Billings, 1932) . I. Right lateral view of a carapace, sample GM1 ( MNHN.F. F63427 ). J. External right of a right valve, sample GM4 ( MNHN.F. F63428 ). – K. Fabalicypris glennensis ( Harlton, 1927) , right lateral view of a carapace, sample 4 (GM5) ( MNHN.F. F63429 ). – L. Fabalicypris sp. , right lateral view of a carapace, sample GM4 ( MNHN.F. F63430 ). – M–N. Orthobairdia texana ( Harlton, 1927) . M. External right of a right valve, sample 4 (GM5) ( MNHN.F. F63431 ). N. External view of a right valve, sample GM1 ( MNHN.F. F63432 ). – O– R. Ceratobairdia mescaleroella Forel sp. nov. O. Holotype, adult, external view of a left valve, sample 4 (GM5) ( MNHN.F. F63433 ). P. A-1, external view of a left valve, sample 4 (GM5) ( MNHN.F. F63434 ). Q. Paratype, A-1, external view of a left valve, sample 4 (GM5) ( MNHN.F. F63435 ). R. A-1, external view of a left valve, sample 4 (GM5) ( MNHN.F. F63436 ). Scale bars: 100 µm.

Remarks

Bairdia sp. A is extremely similar to Bairdia salemensis Geis, 1932 from the Mississippian of Indiana ( Geis 1932) that was later considered as a junior synonym of Bairdia permagna Geis, 1932 by Sohn (1960). Sohn (1960) more precisely stated that the type specimens of Bairdia salemensis are young juveniles of Bairdia permagna , although dimensions provided by Geis for Bairdia salemensis are of Lmean =1450 µm, Hmean= 685 µm. In the present analysis, Bairdia sp. A is morphologically closer to specimens considered as young juveniles of Bairdia permagna than to adults and their dimensions are very similar to those reported for Bairdia salemensis with Lmean =1500 µm, Hmean =500 µm. Herein, however, all specimens at hand assigned to Bairdia sp. A are not abundant enough to discuss their ontogenetic development and verify the conspecificity of the species.

Occurrence

Sample GM1, Quarry section, Williams Ranch Member, Cutoff Formation, Guadalupe Mountains, West Texas, USA, Roadian, Middle Permian (this work).