"Monogenea": 5 genera, 29 species
S001. Dactylogyrus bicorniculus Nitta & Nagasawa, 2016
S002. Trinigyrus peregrinus Nitta & Nagasawa, 2016
S003. Dactylogyrus oryziasi Nitta & Nagasawa, 2017
S004. Furcohaptor brevis Nitta & Nagasawa, 2017
G001. Haplocotyle Nitta & Nagasawa, 2017
S005. Haplocotyle japonica Nitta & Nagasawa, 2017
S006. Gyrodactylus medaka Nitta & Nagasawa, 2018
S007. Benedenia armata Nitta, 2019 [= Armatobenedenia armata (Nitta, 2019) Nitta, 2021]
S008. Neoheterocotyle quadrispinata Nitta, 2019
G002. Platycephalotrema Kritsky & Nitta, 2019
S009. Platycephalotrema ogawai Kritsky & Nitta, 2019
S010. Platycephalotrema koppa Kritsky & Nitta, 2019
S011. Platycephalotrema mastix Kritsky & Nitta, 2019
G003. Latiphagum Nitta, 2019
S012. Gobioecetes longibasis Nitta & Nagasawa, 2020
S013. Microcotyle kasago Ono, Matsumoto, Nitta & Kamio, 2020
S014. Dioncopseudobenedenia elongata Nitta, 2020
S015. Lamellodiscus chin Nitta, 2021
S016. Lamellodiscus egusai Nitta, 2021
S017. Gyrodactylus ajime Nitta, 2021
G004. Gracilobenedenia Nitta, 2021
G005. Armatobenedenia Nitta, 2021
S018. Gracilobenedenia kuremibai Nitta, 2021
S019. Gracilobenedenia hichi Nitta, 2021
S020. Kannaphallus leptosomus Nitta, Kondo, Ohtsuka, Kamarudin & Ismail, 2022
S021. Benedenia kobudai Nitta, 2022
S022. Dactylogyrus tamoroko Nitta & Nagasawa, 2023
S023. Bivaginogyrus japonicus Nitta & Nagasawa, 2023
S024. Bivaginogyrus cingulatus Nitta & Nagasawa, 2023
S025. Bivaginogyrus exiguus Nitta & Nagasawa, 2023
S026. Pseudodiscocotyla mikiae Kamio, Inoue & Nitta, 2023
S027. Microcotyle pacinkar Kamio & Nitta, 2023
S028. Microbothrium myzolepis Nitta & Ota, 2025
S029. Microbothrium cirrhigalei Nitta & Ota, 2025
Trematoda: 1 genus, 2 species
G001. Choanotrema Nitta & Tanaka, 2018
S001. Dollfustrema invadens Saito, Iwata, Nitta & Waki in Saito et al., 2025
S002. Annulocystis carnata Waki & Nitta in Waki et al., 2026
Copepoda: 1 family, 2 species
S001. Lagochondria quadrata Ohtsuka & Nitta, 2019
S002. Biacanthus debera Nitta & Huys, 2025
F001. Pseudotaeniacanthidae Nitta & Huys, 2025
Nematoda: 1 genus, 3 species
S001. Philometra kidakoi Moravec, Nagasawa, Nitta & Tawa, 2019
G001. Congerinema Moravec, Nagasawa, Nitta & Tawa, 2019
S002. Congerinema japonicum Moravec, Nagasawa, Nitta & Tawa, 2019
S003. Raphidascaris (Ichthyascaris) multipapillata Moravec, Nagasawa & Nitta, 2020
Acanthocephala: 2 species
S001. Pseudocavisoma setoense Kita, Nitta & Kajihara, 2024
S002. Pseudoacanthocephalus sadoensis Kita, Nitta, Abe, Kaburagi, Fujita, Toyota, Kondo & Kajihara, 2025
Myxozoa: 2 species
S001. Cardimyxobolus iriomotensis Nitta, 2025
S002. Myxobolus tai Kawano, Nitta, & Yanagida, 2025