AbstractThirteen Neotropical species of Ceratomerus, including nine new species (C. apterus, C. argutus, C. comarapa, C. hibbsi, C. irramus, C. longicornis, C. masneri, C. paraconnexus, C. penai) are described and illustrated. One of these species, C. apterus, from Ecuadorian páramo above 4000 m, lacks wings and has reduced halteres. A preliminary phylogeny of the genera and species groups of the Ceratomerinae is presented, with a discussion of the generic concept of Ceratomerus Philippi. A provisional biogeographic hypothesis of this Gondwanan lineage is discussed. Significant relationships include the Southern Gondwana Pattern, the Inverted Southern Pattern and the Neotropical C. paradoxus group evolved within the Australian C. campbelli group, illustrating both an intra-generic and intercontinental pattern.