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浙江长兴煤山剖面的二叠－三叠系界线层为连续的浮游相沉积没有任何间断，侧向上也是连续的。煤山是长兴阶的层型剖面所在地，长兴阶的上部，界线层和三叠系的下部，每一层都发现有牙形刺，可以逐层追索牙形刺的演化关系。煤山剖面几乎没有任何热力变质（ＣＡＩ＝１—１．５）。煤山剖面的菊石、牙形刺、双壳类、腕足类等多门类化石以及有关事件已得到了很好的研究。绝对年龄和古地磁也已得到深入研究。孢子的存在和易于识别的事件能与陆相地层作很好的对比。煤山剖面交通方便，并得到当地政府的保护。Ｈｉｎｄｅｏｄｕｓｐａｒｖｕｓ最早出现在界线层２的中部，它由Ｈｉｎｄｅｏｄｕｓｌａｔｉｄｅｎｔａｔｕｓ在连续的单相地层中演化而来，存在两个形态型，形态型１极易识别而且容易与它的先躯分子Ｈ．ｌａｔｉｄｅｎｔａｔｕｓ区分开来。二叠－三叠系的生物地层界线以Ｈｉｎｄｅｏｄｕｓｐａｒｖｕｓ的首次出现为准。这个界线在煤山非常接近事件地层界线，仅比事件地层界线高１５ｃｍ，比δＣ１３最低值界线高４ｃｍ。Ｈｉｎｄｅｏｄｕｓｐａｒｖｕｓ在世界各地广泛存在，在集群绝灭事件之后，在由δＣ１３最低值指明的动物群分异度最低值之后，才出现的，并进一步演化出Ｉｓａｒｃｉｃｅｌｌａｉｓ?
The Permian-Triassic boundary line at the Meishan section of Changxing, Zhejiang is continuous with no discontinuities in sedimentation and laterally continuous. Meishan is the site of the Changxing-class stratigraphic section, the upper part of the Changxing order, the boundary line and the lower part of the Triassic. Contiguous spines are found on each floor, and the evolution of conodont can be traced one by one. There is almost no thermal deterioration in the Meishan section (CAI = 1-1.5). Various sections of fossils such as ammonites, conodonts, bivalves, brachiopods and other related fossils from the Meishan section have been well studied. Absolute age and paleomagnetism have also been studied in depth. The presence of spores and easily identifiable events can be well matched with the continental facies. Meishan profile convenient transportation, and get the protection of local government. Hindeodus parvus first appeared in the middle of the boundary layer 2, which evolved from the continuous single-phase strata by the Hindeodus latidentatus. There are two morphological and morphological 1 species that are easy to identify and easily interact with its precursor H. latidentatus distinguish. The Permian-Triassic bio-formation boundary is based on the first occurrence of Hindeodus parvus. This boundary is very close to the event stratigraphic boundary in Meishan, only 15cm above the event stratigraphic boundary and 4cm above the minimum δC13 boundary. Hindeodus parvus is widespread in all parts of the world and appears only after the lowest extinction of the fauna indicated by the lowest δC13 value after the extinction of the cluster and further evolution of Isarcicellais?