The mesomegaloprepids are some of the most abundant fossil damselflies in mid-Cretaceous Burmese amber characterized by large size, brown colour and dense wing venation. Here we described a new damselfly, Cretamegaloprepus zhouae Zheng, Net and Wang, gen. et sp. nov., representing the second known genus and species of Mesomegaloprepidae Huang et al. (2017). Cretamegaloprepus Zheng, Nel and Wang, gen. nov. greatly differs from Mesomegaloprepus Huang et al. (2017) in having no secondary antenodal and antesubnodal crossveins, the Arc being aligned with Ax2, free discoidal and subdiscoidal cells, base of IR2 being very far distal of Sn, shorter CuA ending on posterior wing margin before RP2 base, and a net of irregular cells near base of RP2. The diagnostic characters of Mesomegaloprepidae and Mesomegaloprepus are revised based on the new damselfly. (C) 2018 Elsevier Ltd. All rights reserved.