Simple SummaryCacopsylla, the most species-rich genus of Psyllidae, has around 500 known species worldwide. These insects are known for being host-specific, and some of them are regarded as important pests. Here, we described a new species,Cacopsylla fuscicellasp. nov., which develops on loquats. In addition, we sequenced its mitochondrial genome and used these data to construct a phylogenetic tree of Psyllidae, while also calculating the interspecific genetic distances. Using integrative taxonomy methods, we confirmed that the new species,Cacopsylla fuscicellasp. nov., should be grouped within genusCacopsylla.AbstractPsylloidea, commonly known as jumping plant-lice, have a phloem-sucking habit and strong specificity to their host plants. Within the Psyllidae family, the genusCacopsyllaOssiannilsson, 1970 stands out as being the most diverse, with three species feeding on the genusEriobotryaLindl. In this study, a new psyllid species,Cacopsylla fuscicellasp. nov., was described from China. It is a pest ofEriobotrya japonica(Thunb.) Lindl. and has been cultivated as a commercial fruit tree for years. Illustrations of habitus, morphological structures, and its damage to loquat were also provided. The complete mitochondrial genome ofC. fuscicellasp. nov. was sequenced and annotated. The phylogenetic tree inferred from the maximum likelihood analyses confirmedC. fuscicellasp. nov. as a member of the genusCacopsylla. Genetic distances were generated to assess comparative genetic distances within Psyllinae.