Haplophthalmus mengii
- kingdom: Animalia
- phylum: Arthropoda
- class: Malacostraca
- order: Isopoda
- family: Trichoniscidae
- genus: Haplophthalmus
- species: Haplophthalmus mengii
- Ogulin
Karlovačka
Croatia- Bremerhaven
Bremen- Steinrode
Thuringia
Germany- Maastricht
Limburg
Netherlands- Falkenberg
Halland- Mörbylånga
Kalmar- Majorna
Västra Götaland
Sweden