Cis okennoni Lopes-Andrade and Ferro, new species (Coleoptera: Ciidae), is described from specimens found in Texas (type locality Fort Worth Nature Center and Refuge, Tarrant Co.), Alabama, Mississippi, and Oklahoma, USA. The new species is included in the cayensis species-group, and it is unique within this group in possessing single elytral punctation, an acute outer apical angle of the protibia, and males with the anterior edge of the pronotum projected into two conspicuous horns. The only known breeding record for C. okennoni is in basidiomes of Xylobolus frustulatus (Pers.) Boidin (Russulales: Stereaceae), from which the holotype and most of the type series were collected.