Three females and three nymphs of Ixodes downsi Kohls, 1957 were collected in guano deposited in Guácharos Cave, State of Monagas, Venezuela. The cave is inhabited by bats and oilbirds (Steatornis caripensis Humboldt) and is frequented by carnivores. Previous records of this tick are from Trinidad & Tobago and Peru, and it is unclear whether the principal hosts are Chiroptera or Aves. The present record of I. downsi in Venezuela does not provide new host data but expands this tick's known range, which is probably greater than collections indicate. Phylogenetic analyses based on 16S mitochondrial rDNA sequences of Ixodes species from the Neotropical Zoogeographic Region, plus two Australian Ixodes and three argasids, were conducted to clarify the systematic position of I. downsi. The analyses showed an unexpected relationship with I. (Multidentatus) auritulus Neumann, 1904. However, as with other Neotropical Ixodes, the subgeneric status of I. downsi remains undetermined.