Protacrodontidae, Cappetta, Duffin and Zidek, 1993

Roelofs, Brett, Barham, Milo, Mory, Arthur J. & Trinajstic, Kate, 2016, Late Devonian and Early Carboniferous chondrichthyans from the Fairfield Group, Canning Basin, Western Australia, Palaeontologia Electronica (Barking, Essex: 1987) 262, pp. 1-28 : 17-18

Protacrodontidae gen. et sp. indet.

Figure 7.1-2

Material. A partial tooth from sample OH-4, Gumhole Formation, Oscar Hill, Famennian.

Description. The preserved part of the crown comprises a large triangular cusp and four smaller lateral cusps ( Figure 7.1-2 ) all ornamented with strong linear cristae. The first and second lateral cusps are almost equal in size with the third and fourth cusps diminishing in size distally. On the lingual side of the crown a row of four small rounded cusplets occur between the central and second lateral cusp ( Figure 7.1 ). There is a row of larger, more irregularly shaped cusplets on the entire preserved labial side of the crown ( Figure 7.2 ). A distinct crown-base interface is lacking on the labial side of the tooth. The base is mesio-distally shorter than the crown but extends lingually and is perforated by small pores.

Order HYBODONTIFORMES Cappetta, Duffin and Zidek, 1993

Superfamily HYBODONTOIDEA Owen, 1846

Family LONCHIDIIDAE Herman, 1977

Genus LISSODUS Brough, 1935

Type Species. Lissodus africanus Broom, 1909

Figures

FIGURE 7. Shark teeth from the Upper Devonian Gumhole Formation, Oscar Hill and Lower Carboniferous Laurel Formation, Laurel Downs, Lennard Shelf, Canning Basin, Western Australia. 1-2, Protacrodontidae gen. et sp. indet., WAM 15.6.29, sample OH-4, in lingual (1) and labial (2) views; 3-5, Lissodus sp., WAM 15.6.42, sample TS-1, in lingual (3), occlusal (4) and labial (5) views; 6-7, Hybodontoidea gen. et sp. indet., WAM 15.6.41, sample TS-1, in lingual (6) and labial (7) views; 8-11, Euselachii gen. et sp. indet.1, WAM 15.6.21, sample 198404, in lingual view (8), WAM 15.6.20, sample 198404, in occlusal view (9), WAM 15.6.27, sample 198404, in occluso-lingual view (10), and WAM 15.6.39, sample TS-1 in labial view (11); 12-13, Euselachii gen. et sp. indet. 2, WAM 15.6.40, sample TS-1, in occluso-lingual view (12) and WAM 15.6.22, sample TS-1, in labial view (13); 14-17, Holocephali gen. et sp. indet. 1, WAM 15.6.4, sample 198404, in occlusal view (14), and WAM 15.6.3, sample 198404, in lingual (15), labial (16) and occlusal (17) views. Scale bar length: 1-2, 0.5 mm; 3-5, 0.4 mm; 6-7, 0.75 mm; 8-10, 0.3 mm; 11, 1 mm; 12-13, 0.6 mm; 14-17, 5 mm.