Howardula helenoschini sp. n. (Tylenchida: Allantonematidae) is described from 40 million year-old Baltic amber. The nematodes are parasitic in the body cavity of an adult fly of the genus Triphleba (Phoridae: Diptera). Characteristics of the fossil species are the large size of the pre-adult juveniles and a small number of progeny compared with extant Howardula parasites of flies. Reasons are given why these features suggest that this species was at an early stage of adapting, evolutionarily, to its insect host.
