Cornuodus longibasis ( Lindström, 1955 )

Zhen, Yong Yi, Percival, Ian G. & Webby, Barry D., 2003, Early Ordovician Conodonts from Far Western New South Wales, Australia, Records of the Australian Museum 55 (2), pp. 169-220 : 190

Cornuodus longibasis ( Lindström, 1955)

Fig. 13A–D

Cornuodus longibasis Serpagli,1974:43 , pl.7, fig. 2a,b, pl. 20, fig.21. Cornuodus longibasis .– Cooper, 1981: 161, pl. 26, figs. 10–11. Cornuodus longibasis .– Löfgren,1999: 175–184, pls. 1–3 (cum syn.). Cornuodus longibasis .–Johnston & Barnes, 2000:15, pl. 7, figs.3, 4,

8, 9 (cum syn.). Cornuodus longibasis .–Zhen et al., in press: pl. 2, fig. 19 (cum syn.).

Material. Five specimens from limestone nodules within shales of the upper Yandaminta Quartzite, and 109 specimens from the overlying Tabita Formation at Mount Arrowsmith ; three specimens from unnamed dolomitic limestone unit at Koonenberry Gap .

Remarks. Löfgren (1999) recently defined a septimembrate apparatus for the species. However, we experienced great difficulties in differentiating our specimens, which all seem to be S elements . No P elements have been confirmed in the western New South Wales collections.

Figures

Fig. 13. A–D, Cornuodus longibasis (Lindström, 1955): A, Sa element, AMF120342, Y4–2, lateral view; B, Sa element, AMF120343, M/A11-3, lateral view; C, Sd2 element, AMF120344, M/A11-3, lateral view; D, Sb element, AMF120345, M/A11-2, inner lateral view. E–I, Drepanodus sp.: E, sculponeaform element,AMF120346, C1613, outer lateral view; F, sculponeaform element,AMF120347, W5, inner lateral view; G. arcuatiform element,AMF120348, C1612, inner lateral view; H, arcuatiform element, AMF120349, C1613, outer lateral view; I, graciliform element, AMF120350, Y4–8, outer lateral view. Scale bars 100 µm.