FIGURE 28. Rhadinacanthus longispinus paired and anal spines histology. 1–5 in The diplacanthid fishes (Acanthodii, Diplacanthiformes, Diplacanthidae) from the Middle Devonian of Scotland

FIGURE 28. Rhadinacanthus longispinus paired and anal spines histology. 1–5, sections of spines on articulated fish NMS G.2014.4.32 from Achanarras; 1, transverse section of pectoral fin spine just distal to insertion area; 2, more distal transverse section of pectoral fin spine; 3, 4, longitudinal section of proximal half of anal fin spine; 5, longitudinal section of distal half of pelvic fin spine; 6, 7, NMS G.2014.44.1 from Cromarty, Ross and Cromarty, section through partial articulated specimen; 6, transverse section of pelvic fin spine; 7, transverse section of prepelvic spine. Scale bars equal 1 cm in 3; 0.5 mm in 1–2, 5–7; 0.1 mm in 4.