Lower Permian (Late Kungurian) conodonts from the Sibumasu Terrane, Malaysia: paleoecological, paleobiogeographical and tectonic implications

Abstract

<p>Late Kungurian (Lower Permian) conodonts are described from the Kanthan Limestone, Perak, Peninsular Malaysia and for the first time from the Sibumasu Terrane of the Malay Peninsula. The co-occurrence of <i>Gullodus duani</i>, <i>Gullodus hemicircularis</i>, <i>Gullodus sicilianus</i>, <i>Mesogondolella lamberti</i> and <i>Mesogondolella siciliensis</i> represent the <i>Mesogondolella lamberti</i> International Conodont Zone and the broadly equivalent <i>Mesogondolella siciliensis</i> Regional Conodont Zone. A small fault-bounded basal Pennsylvanian (basal Bashkirian) conodont fauna including <i>Gnathodus girtyi simplex</i> and <i>Declinognathodus inaequalis</i> is also reported. The late Kungurian conodonts from the Kanthan Limestone were deposited in a relatively deep-water environment on the northern passive margin of the Sibumasu Terrane of the eastern Cimmerian Continent located at c. 35o S latitude. Biogeographically, the fauna represents the southern peri-Gondwana Cool Water Province which is consistent with its palaeogeographic location. A new scheme, utilizing characteristics of P1 elements, including position of the 1st denticle, location of 2nd and 3rd denticles, platform shape, platform cross-section, denticle shape in cross-section, and lateral denticle development is proposed for distinguishing between species of the hindeodid genera <i>Gullodus</i>, <i>Hindeodus</i> and <i>Isarcicella</i>. The late Kungurian fauna from the Kanthan Limestone represents the southern peri-Gondwana Cool Water Province supporting palaeogeographic reconstructions placing the Sibumasu Terrane in moderate southern palaeolatitudes in the Kungurian.</p>