Fig. 6 in Stromatoporoids from a Middle Devonian reef in South China and their palaeoecological implication

Fig. 6. Stromatoporoid Clathrocoilona spissa (Lecompte, 1951), from the Jiwozhai reef, Jiwozhai Member, Dushan Formation, Givetian, Middle Devonian; Dushan, Guizhou, South China. A. NIGP 177048; A1, longitudinal section showing the contemporarily encrusting layers, with black and white rectangles illustrating details; A2, A3, enlargement of A1, note the obvious discrepancy between different areas in the same stromatoporoid: the condensed skeletons of A2 are similar to Clathrocoilona spissa (Lecompte, 1951) and thin laminae of A3 are consistent with Clathrocoilona obliterata (Lecompte, 1951). B. NIGP 177049; B1, longitudinal section, note the intra-specific variations (white arrows) of the lower irregular layers similar to Clathrocoilona crassitexta (Lecompte, 1951) and the upper regular layers identical to Clathrocoilona obliterata (Lecompte, 1951); B2, tangential section.