Cateristis eustyla is a species of moth in the family Tineidae. It is the only species in the genus Cateristis. This species is found in New Zealand and Tasmania. It is classified as "Data Deficient" by the Department of Conservation.
Cateristis eustyla was described by Edward Meyrick in 1889 using specimen he found at Riccarton Bush in December. In 1928 George Hudson discussed the species. The lectotype specimen is held at the Natural History Museum, London.
Meyrick described the species as follows:
This species is found in New Zealand. It is also found in Tasmania. This species has not been recorded in New Zealand since 1882.
This species frequents forest habitat.
This species has been classified as having the "Data Deficient" conservation status under the New Zealand Threat Classification System.