The “Panghkawkwo graptolite bed” (Llandovery, Silurian), Myanmar and the location of the Sibumasu (or Sibuma) Terrane in the Silurian

The “Panghkawkwo graptolite bed” is shown to comprise several graptolitic horizons extending through the Aeronian (middle Llandovery) and into the lower Telychian (upper Llandovery). Graptolite assemblages are diverse indicating an outer shelf (or deeper) depositional environment. They are similar to those of Bohemia and Saudi Arabia (peri-Gondwanan Europe and core Gondwana respectively), but include also taxa (Agetograptus and species of Metaclimacograptus) not known from these regions, but which characterize lower latitude Llandovery graptolite assemblages. The evidence for the Silurian location of the Sibuma(su) Terrane is discussed. The presence of Monograptus belophorus and Cyrtograptus rigidus in the lower Sheinwoodian (Wenlock) of western Yunnan suggests a non-equatorial palaeolatitude. The Panghkawkwo graptolites suggest a location for Sibuma(su) between Gondwana and South China.