Bairdia nanbiancunensis Wang, 1988

Guillam, Elvis, Forel, Marie-Béatrice, Song, Junjun & Crasquin, Sylvie, 2022, Late Devonian-early Carboniferous ostracods (Crustacea) from South China: taxonomy, diversity and implications, European Journal of Taxonomy 804, pp. 1-62 : 35-36

Bairdia nanbiancunensis Wang, 1988

Fig. 10D–E

Bairdia nanbiancunensis Wang, 1988b: 239 , pl. 60 figs 9–12.

Bairdia nanbiancunensis – Olempska 1999: 428, fig. 29h. — Jones: unpublished data, fide Olempska 1999.

Bairdia sp. – Coen 1989: 317, pl. 2 figs 2 – 3.

non Bairdia beichuanensis Wei, 1983 – Song & Gong 2019: Song & Gong 2019: fig. 5a.

Material examined

CHINA • 1 complete carapace ( Fig. 10D ); Blue Snake section, Gelaohe Formation, sample 19BAI 69; P6M 3940 • 1 complete carapace ( Fig. 10E ); Blue Snake section, Gelaohe Formation, sample 19BAI 68; P6M 3941 • 4 complete carapaces; Blue Snake section, Gelaohe Formation, samples 19BAI 67, 19BAI 69, 19BAI 80. All from the Famennian, late Devonian.

Dimensions

RV: L = 941–2112 µm, H = 516–1050µm, H/L = 0.48–0.56.

LV: L = 941–2136 µm, H = 536–1332 µm, H/L = 0.57–0.65.

Remarks

This species is rare in the studied material. Bairdia beichuanensis Wei, 1983 in Song & Gong (2019) from the Famennian and the Tournaisian of the Baihupo section, Guizhou, South China ( Song & Gong 2019) does not belong to Bairdia beichuanensis as shown by the strong ventral and dorsal overlap and stocky morphology. Based on these characters, it is here reattributed to Bairdia nanbiancunensis Wang, 1988 . Coen (1989) reported Bairdia sp. from the Gelaohe Formation, Baihupo section, Guizhou, South China, Famennian. Following Olempska (1999), we consider that it belongs to Bairdia nanbiancunensis . The specimens shown in Coen (1989: pl. 2 gigs 2b, 3b) and in Song & Gong (2019: fig. 5a) have a size similar to our material with respectively L = 1000–1100 µm, H = 650–675 µm, H/L = 0.59–0.67 and L = 1120µm, H = 706µm, H/L = 0.63. The specimen shown in Olempska (1999: fig. 29h) is as long as our biggest specimen and higher (L = 2310µm, H = 1540 µm, H/L = 0.67) but we consider that these differences are intraspecific variability. Three ontogenetic stages (A-2 to Ad) are present in our material; they only differ by the size without major changes throught ontogeny.

Occurrence

Nanbiancun, Guilin, South China, middle Tournaisian, ( Wang 1988b). Gelaohe Formation, Baihupo section, Guizhou, South China, Famennian, late Devonian ( Coen 1989). Muhua Formation, Guizhou, South China, early Carboniferous (Olempska 1999). Laurel Formation, Canning Basin, Western Australia, Tournaisian, early Carboniferous (Jones, unpublished data, fide Olempska 1999). Gelaohe and Tangbagou Formation, Blue Snake section, Guizhou, South China, Famennian–Tournaisian, late Devonian–early Carboniferous ( Song & Gong 2019). Samples 19BAI 67, 19BAI 69, 19BAI 80, Blue Snake section, Gelaohe Formation, Famennian, late Devonian (this work).

Figures

Fig. 10. SEM pictures and focus stacking method pictures (with an *) of ostracods from Blue Snake section, Dushan County, South China, late Famennian–Tournaisian, late Devonian–early Carboniferous. All specimens are temporarily housed in the collections of Sorbonne Université, Paris, France (SU). A. Bairdia feliumgibba Becker, 1982, right lateral view of a carapace, sample 19BAI 01 (P6M 3937). B. Bairdia hypsela Rome, 1971, right lateral view of a carapace, sample 19BAI 03 (P6M 3938). C. Bairdia mnemonica Schevtsov, 1964 in Crasquin, 1986, right lateral view of a carapace, sample 19BAI 03 (P6M 3939).D–E. Bairdia nanbiancunensis Wang, 1988.D. Right lateral view of a carapace*, sample 19BAI 69 (P6M 3940). E. Right lateral view of a carapace, sample 19BAI 68 (P6M 3941). F. Bairdia natiformis Buschmina, 1970, right lateral view of a carapace, sample 19BAI 01 (P6M 3942). G–I. Bairdia obliqua Rozhdestvenskaya, 1972. G. Adult, right lateral view of a carapace, sample 19BAI 01 (P6M 3943). H. A-1, right lateral view of a carapace, sample 19BAI 01 (P6M 3944). I. A-2, right lateral view of a carapace, sample 19BAI 01 (P6M 3945). J. Bairdia quasikuznecovae Buschmina, 1968, right lateral view of a carapace, sample 19BAI 74 (P6M 3946). K. Bairdia rustica Kotchetkova, 1983, right lateral view of a carapace, sample 19BAI 08 (P6M 3947). L. Bairdia semichatovae Tschigova, 1960, right lateral view of a carapace, sample 19BAI 68 (P6M 3948). M. Bairdia solita Buschmina, 1970, right lateral view of a carapace, sample 19BAI 41 (P6M 3949). N. Bairdia submongolensis Buschmina, 1968, right lateral view of a carapace, sample 19BAI 08 (P6M3950).O.Bairdiacf.altifrons Knight, 1928inCrasquin,1984,right lateralviewof acarapace,sample 19BAI 43 (P6M 3951). P. Bairdia cf. extenuata Nazarova, 1951, right lateral view of a carapace, sample 19BAI 60 (P6M 3952). Q. Bairdia cf. grahamensis Harlton, 1928, right lateral view of a carapace, sample 19BAI 08 (P6M 3953). R. Bairdia cf. susoroides Jiang, 1983, right lateral view of a carapace, sample 19BAI 69 (P6M 3954). S. Bairdia sp. 1, right lateral view of a carapace, sample 19BAI 54 (P6M 3955). T. Bairdia sp. 2, right lateral view of a carapace, sample 19BAI 43 (P6M 3956). U. Bairdia sp. 3, right lateral view of a carapace, sample 19BAI 05 (P6M 3957). Scale bars = 100 µm.