Taxonomic placement of the enigmatic monotypic Mexican longhorned beetle genus Vesperoctenus Bates is examined through inclusion in and reanalysis of the dataset of Haddad et al. (2018, Systematic Entomology 43: 68–89). We describe and discuss the phylogenetic significance of the internal structures of a recently collected V. flohri female from the Sierra de la Laguna mountain range in Mexico, the same specimen from which phylogenomic data was generated. Our phylogenomic analyses (469 genes) recovered Vesperoctenus with maximal statistical support within the cerambyciform family Vesperidae, sister to Vesperus Dejean (Vesperinae). Vesperus + Vesperoctenus were recovered sister to Philinae, and collectively form a clade sister to Anoplodermatinae. Thus, we place V. flohri within Vesperidae: Vesperinae: Vesperoctenini based on analyses of large-scale phylogenomic data. Finally, we propose that the conservation status of V. flohri merits assessment.