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The Silurian to Devonian Gionyama Formation is assigned to the Kurosegawa Terrane in Southwest Japan. Abundant rugose corals in the Middle Member (late Llandovery to early Ludlow) of this formation represent 18 species belonging to 13 genera. These species are: <i>Tryplasma </i>sp. aff. <i>T</i>. <i>ozakii</i>, <i>Tryplasma </i>sp. A, <i>Tryplasma </i>sp. B, <i>Cystiphyllum </i>sp., <i>Holmophyllum </i>sp., <i>Holmophyllum</i>? sp., <i>Labechiellata regularis</i>, <i>Rhizophyllum </i>sp. A, <i>Rhizophyllum </i>sp. B, <i>Neobrachyelasma japonica</i>, <i>Pseudamplexus </i>sp., <i>Amsdenoides </i>sp., <i>Amplexoides </i>sp. aff. <i>A</i>. <i>chaoi</i>, <i>Strombodes </i>sp., <i>Nanshanophyllum hamadai</i>, <i>N</i>. <i>gokasense</i>, <i>Shensiphyllum </i>sp., and <i>Ptychophyllum </i>sp. The rugose corals from the Gionyama Formation include cosmopolitan genera that commonly occur in China, Kazakhstan, Siberia, Gotland, eastern Australia, and North America. Endemic genera, such as <i>Nanshanophyllum </i>and <i>Shensiphyllum</i>, which only occur in South China and Qaidam, are also present. Their stratigraphic ranges are restricted to the late Llandovery. The occurrences of these endemic genera may indicate a strong paleobiogeographic relation between the South China Block and "Proto-Japan" during the Silurian

Coral diversity and extinction patterns in the Permian of China are revealed through statistical analyses of 56 coral families, 263 genera and 2100 species from five consecutive time intervals. The highest coral diversity is in the Chuanshanian, with 753 species, 167 genera and 39 families. In contrast, the lowest diversity is in the Changhsingian, with only 68 species, 20 genera and 10 families. Two decreases in diversity can be recognized during the Permian. The first occurred at the end of the Maokouan (end‐Guadalupian) and is marked by the loss of 75.6% of coral families, 77.8% of coral genera and 82.2% of coral species. The second major diversity drop took place at the end of the Changhsingian, when all rugose and tabulate corals became extinct. The extinction at the end of the Guadalupian in Pangea may be related to the middle Permian global regression. However, in South China the end‐Maokouan extinction may be related to the eruption of the Omeishan Basalt. A triple‐zoned palaeobiogeographical pattern is well expressed by coral diversity.

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