Leporinus reinhardti (Lütken)

Scharcansky, Alexandre & Lucena, Carlos Alberto S., 2008, Phylogenetic assessment of ultrastructural and histological characters of teeth in the Anostomoidea, Hemiodontidae and Parodontidae (Teleostei: Ostariophysi: Characiformes), Zootaxa 1948 (1), pp. 36-56 : 40

Leporinus reinhardti (Lütken) ( Figs. 3 , 4 , and 5)

The bone tissue close to the teeth is compact, without apparent alveoli. Replacement teeth are arranged in a single row and aligned with their respective functional tooth and lodged in trenches. The teeth show comparable developmental stages, and there is no pre-eruptive rotation. Histologically, the replacement teeth in their final stage of development show a pattern similar to that of functional teeth from the exterior inwards: a narrow enamel layer (light area of the tooth, see Figure 5C ), which, because it was totally mineralized, was decalcified during the tissue preparation process, surrounded by elongated ameloblasts. Next, are the dentin layer and the set of odontoblasts, the same size as the ameloblasts. Finally, the dental papilla (mesenchymal cells) forms a narrow area.

The functional teeth show a protrusive arm from their widest area by which they are supported on the internal epithelial tissue of the dentary ( Fig 4A,B ). The dentin layer is equally narrow all around the teeth. The dental pulp, located anterior to the horizontal line that goes through the bone-tooth connection, is narrow and approximately the same width as the tooth base; apparently, its posterior border is connective tissue ( Fig. 5D ).

Figures

FIGURE 3. Leporinus reinhardti (Lütken, 1875) MCP 17146, 82.72 mm SL – A and B: Premaxilla and teeth, left side, frontal view. C: Premaxilla tooth, frontal view, incisal region. D: Contact zone of tooth-premaxilla bone, frontal view. E: Premaxilla tooth, left side, SEM image showing the crystal apatite arrangement, labiolingual direction.

FIGURE 4. Leporinus reinhardti (Lütken, 1875) MCP 17146, 82.72 mm SL – A: Premaxilla and teeth, left side, medial view. B: Premaxilla and teeth, medial view, contact detail of tooth-premaxilla surface.

FIGURE 5. Leporinus reinhardti (Lütken, 1875). MCP 17146, 82.72 mm SL – A: Dentary, cross section (10x). B: Arrows point to the apical region of replacement teeth. C: Replacement tooth (40x). D: Attachment region of functional teeth (20x). E: Dentary, cross section, detail of the tissue supporting the functional teeth. AM=ameloblasts; DE=dentary; DF=functional teeth; DN=dentin; DS=replacement teeth; ES=enamel; OD=odontoblasts; PA= dental papilla; PO=pulp; TC=connective tissue; TE=epithelial tissue; TO=bone tissue.