| Summary: | <i>Hadrotreta</i> is a worldwide acrotretoid brachiopod reported from the Cambrian Series 2 to Miaolingian. Here, a number of well-preserved fossils of <i>Hadrotreta</i>, identified as <i>Hadrotreta</i> cf. <i>H</i>. <i>timchristiorum</i>, were found in the <i>Protoryctocephalus arcticus</i> Zone of the Tsinghsutung Formation of Cambrian Series 2, Stage 4 in Jianhe, Guizhou, south China. This is the first report of <i>Hadrotreta</i> in China, which enriches its global palaeogeographical distribution. <i>Hadrotreta</i> is very similar to acrotretoids such as <i>Kostjubella</i>, <i>Vandalotreta</i>, <i>Linnarssonia</i>, and <i>Eohadrotreta</i>. It differs from them with its well-developed ventral boss-like apical process, apical pits, and dorsal median sulcus. In view of the palaeogeography of <i>Hadrotreta</i>, this genus was mainly distributed in low-latitude regions. <i>Hadrotreta</i> was only found in south China and Laurentia during the Cambrian Age 4, then expanded its distribution to other regions such as Siberia, Baltica, the Kazakh Terranes, the Far East, and Gondwana Pange during the Miaolingian Epoch. <i>Hadrotreta</i> seems to have shifted from deeper water to shallow-water environments during the period from the Cambrian Series 2 to the Miaolingian.
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