Westergaardodina

Chosonodina herfurthi, from Lehnert et al. (2005).

Belongs within: Conodonta.

Westergaardodina was a long-lived paraconodont genus found from the Middle or Late Cambrian to the Middle Ordovician. It had W- or U-shaped elements that Müller & Hinz-Schallreuter (1998) explained as growing through a combination of dorsal and/or lateral pressure being applied to points on a growing element. How the Westergaardodina elements were arranged in their original apparatus remains unknown.

Druce & Jones (1971) suggested a phylogenetic connection between Westergaardodina and the Ordovician genus Chosonodina with palmate elements bearing a higher number of denticles (up to seven).

Characters (from Müller & Hinz-Schallreuter 1998): Bi- or tricuspidate elements; internal cavity may be divided between lateral cavities. Lateral projection(s) (one-sided only in bicuspidate forms) resulting from combination of upward growth from base and dorsal pressure alongside/on either side of median projection causing tearing of older lamellae; lamellae-free spaces became filled by a callus-like substance. Lateral projections of elements remain flexible; probably not heavily mineralised in life.

<==Westergaardodina Müller 1959 DJ71 [Westergaardodinidae]
    |  i. s.: W. mosseburgensis Müller 1959 DJ71
    |--*W. bicuspidata Müller 1959 DJ71
    `--+--W. amplicava Müller 1959 DJ71
       `--Chosonodina Müller 1964 DJ71
            |  i. s.: C. rigbyi PBJ03
            |--C. fisheri Druce & Jones 1971 DJ71
            `--+--*C. herfurthi Müller 1964 DJ71
               `--+--C. lunata Harris & Harris 1965 DJ71
                  `--Coleodontidae [Trucherognathidae] H62
                       |--Hindeodellinae H62
                       |    |--Cervicornoides Stauffer 1938 H62
                       |    |    `--*C. alternatus Staffer 1938 H62
                       |    |--Kladognathus Rexroad 1958 [=Cladognathus Rexroad 1957 non Burmeister 1847] H62
                       |    |    `--*K. prima (Rexroad 1957) [=*Cladognathus prima] H62
                       |    |--Metaprioniodus Huddle 1934 H62
                       |    |    `--*M. biangulatus Huddle 1934 H62
                       |    `--Hindeodella Bassler 1925 H62
                       |         |--*H. subtilis Ulrich & Bassler 1926 H62
                       |         `--H. qipanensis CB86
                       |--Coleodontinae [Trucherognathinae] H62
                       |    |--Coleodus Branson & Mehl 1933 DJ71, SS05
                       |    |    `--*C. simplex Branson & Mehl 1953 H62
                       |    |--Arcugnathus Cooper in Cooper & Sloss 1943 H62
                       |    |    `--*A. tenuis Cooper in Cooper & Sloss 1943 H62
                       |    |--Branmehla Hass 1949 H62
                       |    |    `--*B. inornata (Branson & Mehl 1934) [=Spathodus inornatus] H62
                       |    |--Hindeodina Hass 1959 H62
                       |    |    `--*H. simplaria Hass 1959 H62
                       |    |--Pravognathus Stauffer 1936 (see below for synonymy) H62
                       |    |    `--*P. idonea (Stauffer 1935) [=*Heterognathus idonea] H62
                       |    `--Trucherognathus Branson & Mehl 1933 H62
                       |         `--*T. distorta Branson & Mehl 1933 H62
                       `--Lonchodininae H62
                            |--Lonchodina Bassler 1925 H62
                            |    `--*L. typicalis Ulrich & Bassler 1926 H62
                            |--Apatognathus Branson & Mehl 1934 H62
                            |    `--*A. varians Branson & Mehl 1934 H62
                            |--Curtognathus Branson & Mehl 1933 H62
                            |    `--*C. typa Branson & Mehl 1933 H62
                            |--Trichonodella Branson & Mehl 1948 (see below for synonymy) H62
                            |    |--*T. prima (Branson & Mehl 1933) [=*Trichognathus prima] H62
                            |    `--T. inconstans TC71
                            `--Erismodus Branson & Mehl 1933 H62
                                 |--*E. typus Branson & Mehl 1933 H62
                                 |--E. asymmetricus PBJ03
                                 `--E. radicans H62

Pravognathus Stauffer 1936 [=Heterognathus Stauffer 1935 nec Girard 1854 nec Schmarda 1859 nec King 1864 nec Rey 1888] H62

Trichonodella Branson & Mehl 1948 [=Trichognathus Branson & Mehl 1933 nec Berthold 1827 nec Gemminger & Harold 1868] H62

*Type species of generic name indicated

REFERENCES

[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.

[DJ71] Druce, E. C., & P. J. Jones. 1971. Cambro-Ordovician conodonts from the Burke River Structural Belt, Queensland. Commonwealth of Australia, Bureau of National Development, Bureau of Mineral Resources, Geology and Geophysics, Bulletin 110: 1–159.

[H62] Hass, W. H. 1962. Conodonts. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt W. Miscellanea: Conodonts, Conoidal Shells of Uncertain Affinities, Worms, Trace Fossils and Problematica pp. W3–W69. Geological Society of America, and University of Kansas Press.

Müller, K. J., & I. Hinz-Schallreuter. 1998. Internal structure of Cambrian conodonts. Journal of Paleontology 72 (1): 91-112.

[PBJ03] Pyle, L. J., C. R. Barnes & Z. Ji. 2003. Conodont fauna and biostratigraphy of the Outram, Skoki, and Owen Creek Formations (Lower to Middle Ordovician), Wilcox Pass, Alberta, Canada. Journal of Paleontology 77 (5): 958–976.

[SS05] Sansom, I. J., & M. P. Smith. 2005. Late Ordovician vertebrates from the Bighorn Mountains of Wyoming, USA. Palaeontology 48 (1): 31–48.

[TC71] Thomson, K. S., & K. S. W. Campbell. 1971. The structure and relationships of the primitive Devonian lungfish—Dipnorhynchus sussmilchi (Etheridge). Yale University Peabody Museum of Natural History Bulletin 38: 1–109.