Bairdia

Bairdia, copyright Moorea Biocode.

Belongs within: Bairdiidae.

Bairdia is a genus of ostracods with a fossil record extending from the Ordovician to the present day. As such, it is the longest-surviving recognised genus of ostracods and probably represents the only lineage of Bairdiidae to survive from the Palaeozoic into the Mesozoic (Benson et al. 1961).

Characters (from Benson et al. 1961): Carapace mostly elongate fusiform in lateral view, with broadly arched dorsum that becomes concave terminally, especially at the rear; venter centrally straight but curved upward terminally so that extremities are nearly at mid-height, anterior end generally higher and better rounded than posterior, which is generally acuminate; in dorsal view, lateral outlines symmetrically convex and extremities acuminate; surface of valves smooth, punctate, or rarely with protuberances; left valve larger than right valve, mostly overreaching it around entire margin and overlapping it, especially ventrally, around contact margin. Short ridge-and-groove hingement commonly marked by prominent cardinal angles, especially in right valve; contact margins complex, with wide duplicature, vestibule, and associated structures; adductor-muscle scar pattern of several discrete spots.

<==Bairdia M’Coy 1844HM04 (see below for synonymy)
    |--*B. curtus McCoy 1844BB61
    |--B. acuminata Cooper 1946HM04
    |--B. aliger (Guseva 1971)ZL87
    |--B. altiacutaCB86
    |--B. beedeiCB86
    |--B. bicornis Bradfield 1935ZL87
    |--B. calidaCB86
    |--B. citriformisCB86
    |--B. crassa Harlton 1929HM04
    |--B. cristataCB86
    |--B. cultrijugatiL05
    |--B. deloi (Bradfield 1935)ZL87
    |--B. demissaCB86
    |--B. eissensis Upson 1933ZL87
    |--B. firmataZL87
    |--B. formosaBB61
    |--B. frequensHKS61
    |--B. garrisonensis Upson 1933S82
    |--B. girtyi Sohn 1960HM04
    |--B. golcondensisBB61
    |--B. grahamensis Harlton 1928HM04
    |--B. guanxiensis Guan 1978CB86
    |--B. harltoni Cooper 1946HM04
    |--B. hassi Sohn 1960ZL87
    |--B. kwanshanensisCB86
    |--B. lungtanensisCB86
    |--B. mandelstamiCB86
    |--B. marginicompressa Chen & Bao 1986CB86
    |--B. menardensis Harlton 1929ZL87
    |--B. modicaCB86
    |--B. monstrabilis Cooper 1946ZL87
    |--B. oklahomensisBB61
    |--B. permagna Geis 1932HM04
    |--B. piscariformisCB86
    |--B. pompilioides Harlton 1928HM04
    |--B. postacutaCB86
    |--B. radlerae Kellett 1934ZL87
    |--B. seminalis (Kellett 1934)ZL87
    |--B. symmetricaZL87
    |--B. trianguliformisCB86
    |--B. verdesensis LeRoy 1943S-VC91
    |--B. verwiebeiZL87
    |--B. whitesidei Bradfield 1935HM04
    `--B. zhongyingensis Wang 1978CB86

Bairdia M’Coy 1844HM04 [incl. Acratinella Schneider 1956BB61, Morrisites Gibson 1955 non Buckman 1921BB61, Morrisitina Gibson 1955BB61, Nesidea Costa 1849BB61]

*Type species of generic name indicated

References

[BB61] Benson, R. H., J. M. Berdan, W. A. van den Bold, T. Hanai, I. Hessland, H. V. Howe, R. V. Kesling, S. A. Levinson, R. A. Reyment, R. C. Moore, H. W. Scott, R. H. Shaver, I. G. Sohn, L. E. Stover, F. M. Swain & P. C. Sylvester-Bradley. 1961. Systematic descriptions. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt Q. Arthropoda 3: Crustacea: Ostracoda pp. Q99–Q421. Geological Society of America and University of Kansas Press.

[CB86] Chen D.-Q. & Bao H. 1986. Lower Permian ostracodes from the Chihsia Formation of Jurong and Longtan, Jiangsu Province. Acta Micropalaeontologica Sinica 3 (2): 107–132.

[HM04] Hoare, R. D., & G. K. Merrill. 2004. A Pennsylvanian (Morrowan) ostracode fauna from Texas. Journal of Paleontology 78 (1): 185–204.

[HKS61] Howe, H. V., R. V. Kesling & H. W. Scott. 1961. Morphology of living Ostracoda. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt Q. Arthropoda 3: Crustacea: Ostracoda pp. Q3–Q17. Geological Society of America and University of Kansas Press.

[L05] Liebau, A. 2005. A revised classification of the higher taxa of the Ostracoda (Crustacea). Hydrobiologia 538: 115–137.

[S-VC91] Segura-Vernis, L. R., & A. L. Carreño. 1991. Foraminíferos y ostrácodos de la Laguna de La Paz, Baja California Sur, México. Inv. Mar. CICIMAR 6 (1): 195–224.

[S82] Shi C.-G. 1982. Some early Carboniferous ostracodes from Nylam, Xizang (Tibet). Acta Palaeontologica Sinica 21 (3): 309–314.

[ZL87] Zhang X.-J. & Liang X.-Y. 1987. Ostracoda from the Taiyuan Formation of Xingyang and Gong Xian districts, Henan. Acta Micropalaeontologica Sinica 4 (3): 293–312.

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