The rove beetle rubfamily Solierunae represents a small and phylogenetically distinct lineage, currently comprising oily a single extant genus, Solierius Bernhauer, which is endemic to South America. The fossil record of this subfamily includes five extinct species assigned to the extinct genus Prosolierius, discovered in Barremian Cenomanian amber deposits from Lebanon, Spain, and northern Myanmar. Here we describe a new species of Solieriinae, Frosoliertus qizhihaoi sp. nov., based on an exceptionally well-preserved specimen from the mid-Cretaceous Kachin amber. This new species exhibits clore morphological similarities to Prosolierius thayerae Yamamoto, particularly in the elongation of antennomere 11 and the narrow genital segments. However, P. qizhihaoi can be distinguished by its elongate and slender antennomere 3, as well as the distinctly oval-shaped antennomere 4. The discovery of these fossil species within Prosolierius highlights the previously unrecognized palaeodiversity of Solieriinae rove beetles during the late Mesozoic, providing new insights into the evolutionary
history of the enigmatic subfamily. LSID code www.zoobank.org/urn:lsid:zoobank.org:act:F1C95B5A-BD6D-4F84-9803-8DD25CDFBAE2