Figure 4. – Lepisosteus platostomus. A-C in Histological characteristics of lower jaw bones and oral teeth of the short nose gar, Lepisosteus platostomus Rafinesque, 1820 (Lepisosteidae)

Figure 4. – Lepisosteus platostomus. A-C: Lower right jaw, transverse sections, natural transmitted light. A: Dentary. Primary bone with canaliculi of Williamson is dominating but with some areas of secondary bone around some vascular cavities. A patch of multilayered ganoine is seen (white asterisk) and the white arrowheads point to small secondary vascular canals. Scale bar = 50 μm. B: Detail of the inset 1 of Fig. 4A showing primary bone (bo) and secondary bone (black asterisks) with canaliculi of Williamson (arrowheads) present in the two types of bone tissues. Scale bar = 50 μm. C: Detail of the inset 2 of Fig. 4A showing several ramified canaliculi of Williamson (arrowheads). Scale bar = 50 μm. D: Scale. Transverse section, natural transmitted light. The bony basal plate (bp) shows the canaliculi of Williamson that are relatively parallel and with very few branchings. (G = ganoine). Scale bar = 200 μm. E: Coronoid bone. Detail of bony tissue showing several osteocytes (arrows) with their canaliculi. Scale bar = 10 μm. F: Coronoid bone. Detail of the base of a tooth (de) showing attachment bone (ab), primary bone (bo) and a vascular canal (vc) surrounded by secondary bone that is discordant (arrowheads) relatively to the primary bone. Scale bar = 5 μm.