From: Dentition and feeding in Placodontia: tooth replacement in Henodus chelyops
Taxon | Â | Paraplacodus | Placodus | Cyamodus | Placochelys | Psephoderma | Henodus |
---|---|---|---|---|---|---|---|
Premaxillary teeth | Number & Shape | 3 long, procumbent and pointed | 3 long, procumbent, spatulated and widely spaced | 1 to 2 reduced and blunt | 0 | 0 | 0 |
Maxillary teeth | Number & Shape | 7 max. low and rounded with a central cusp | 3–5 low and rounded (« bulbous») with a central cusp | 2–3 hemispherical | 3 flattened | 2 flattened (posterior one is elliptical) | 0 |
Size | Quite large | Quite large | Increasing rearwards | Increasing rearwards | Posterior one is larger | - | |
Palatine teeth | Number & Shape | 4 low (3 posterior are rectangular) | 3 quadrangular | 2–3 circular or elliptical | 2 flattened with a central cusp | 2 Flattened with a central cusp (posterior one is ovoid) | 1 with a flat crown and covered by fine pits |
Size | More large than maxillary teeth | Large | Very big (posterior one is the tallest) | Very big (posterior one is the tallest) | Very big (posterior one is the tallest) | Quite small | |
Rostrum | Shape | Wide | Wide | Narrow | Narrow, edentulous | Very thin and long, edentulous | Rectangular and wide, denticles |