Rediscovery of Forcipomyia (Trichohelea) opilionivora (Lane, 1947) (Diptera, Ceratopogonidae) in Brazil after 75 years

The species Forcipomyia (Trichohelea) opilionivora (Lane, 1947) (Diptera, Ceratopogonidae) was rediscovered in the state of Rio de Janeiro, Brazil, 75 years after its original description. This study aimed to investigate the ectoparasitic relationship between F. (T.) opilionivora and its host and document its occurrence, which was recorded serendipitously during the collection of Opiliones (harvestmen) specimens in Parque Nacional do Itatiaia in the state of Rio de Janeiro, Brazil. After the collection, both specimens were subjected to photographic documentation and preserved for further examination. This study presents the first photographic record of the ectoparasitic relationship between F. (T.) opilionivora and a harvestman, shedding light on a poorly studied interaction. The host specimen was identified as a female of Holcobunus nigripalpis Roewer, 1910 (Opiliones, Sclerosomatidae), a gagrelline commonlyfound in the Atlantic Forest of southeastern Brazil. Previous records of ectoparasitism between Ceratopogonidae and harvestmen were limited to the family level (Sclerosomatidae species, specifically Gagrellinae or Leiobuninae). However, no specific host species had been identified until now. The rediscovery of F. (T.) opilionivora, along with the identification of its host, addresses a significant gap in our knowledge regarding the biology and distribution of this species and provides valuable insights into the intricate relationships between biting midges and arachnids. This study emphasizes the need for further investigations into the biology of these ectoparasitic species and underscores the importance of documenting and studying lesser-known interactions within ecosystems.