Fig. 19 in Fossil freshwater sponges: Taxonomy, geographic distribution, and critical review

Fig. 19. Oncosclera kaniensis Matsuoka and Masuda, 2000, Spongillida: Potamolepidae, TMNH; Nakamura Formation, early Miocene, River bed on the Kiso River, Dota, Gifu Prefecture, Central Japan. A. Sponge encrusting a shell (Anodonta, Mollusca, Bivalvia). B. Sponge encrusting a wood fragment retaining its annual rings. C. Gemmule (cross section). D. Megascleres. E. Oxea tip (megasclere). F. Strongyles tips (megasclere). G. Strongyles gemmuloscleres). H. Spiny tips of strongyles (gemmuloscleres). I. Strongyle and oxea (megascleres). J. Strongyles (gemmuloscleres). A, B, explanatory drawings; C–H, SEM images; I, J, drawings of the spicular complement. Modified from Matsuoka and Masuda (2000).