Figure 2. – Lepisosteus platostomus. A in Histological characteristics of lower jaw bones and oral teeth of the short nose gar, Lepisosteus platostomus Rafinesque, 1820 (Lepisosteidae)

Figure 2. – Lepisosteus platostomus. A: External view of the left lower jaw showing the caniniform teeth on the labial side of the jaw. The largest tooth (arrow) is located at the anterior tip of the jaw. On the lingual side of the jaw there are small sharp teeth (arrowheads). Scale bar = 5 mm. In the inset a detail of a caniniform tooth showing the external ridges at its base (arrowhead). Scale bar = 1 mm. B-D: Right jaw. B: Cross section of the jaw (microradiograph) showing five small teeth inserted on a coronoid bone (upper left) plus a larger tooth on the dentary. The white asterisk indicates the unmineralized Meckel's cartilage on the left hand side of the dentary (de). Scale bar = 2.5 mm. In the inset a microradiograph of a caniniform tooth and its attachment bone (bo), also showing its dentine core (arrowhead) with the apical acrodin cap (arrow). C: Parasagittal median section of the jaw (microradiograph) showing five caniniform teeth. The dentine folds occupy the total height of the pulp cavities. On the left one can also see five hypermineralized acrodin caps. Scale bar = 2 mm. D: Parasagittal lingual section of the jaw (microradiograph) showing the small lingual teeth series some of them showing minute mineralized folds in the pulp cavity. Scale bar = 1 mm.