Belongs within: Sigmodontinae.
The Scapteromyini are a group of fossorial and semi-aquatic mice found in central South America. The group has been recognised to include the genera Scapteromys, Kunsia and Bibimys but its monophyly has been questioned.
ScapteromyiniN10
|--+--ScapteromysFS15
| | |--S. aquaticusL07
| | `--S. tumidus (Waterhouse 1837)L07
| `--KunsiaFS15
| |--K. frontoIT07
| `--K. tomentosusIT07
`--+--BibimysFS15
| |--B. labiosus (Winge 1887)FS15, N10 [=Scapteromys labiosusN10]
| `--+--B. chacoensisFS15
| `--B. torresiFS15
`--+--Lenoxus apicalisFS15
`--+--Blarinomys brevicepsFS15
`--BrucepattersoniusFS15
|--B. albinasusFS15
|--B. griserufescensFS15
|--B. guaraniFS15
|--B. igniventrisFS15
|--B. iheringiFS15
|--B. misionensisFS15
|--B. paradisusFS15
`--B. soricinusFS15
*Type species of generic name indicated
References
[FS15] Faurby, S., & J.-C. Svenning. 2015. A species-level phylogeny of all extant and late Quaternary extinct mammals using a novel heuristic-hierarchical Bayesian approach. Molecular Phylogenetics and Evolution 84: 14–26.
[IT07] Isaac, N. J. B., S. T. Turvey, B. Collen, C. Waterman & J. E. M. Baillie. 2007. Mammals on the EDGE: conservation priorities based on threat and phylogeny. PloS One 2 (3): e296.
[L07] Lareschi, M. 2007. Seasonal occurrence of ectoparasites associated with the water rat Scapteromys aquaticus (Muridae, Sigmodontinae) from Punta Lara, Argentina. In: Morales-Malacara, J. B., V. M. Behan-Pelletier, E. Ueckermann, T. M. Pérez, E. G. Estrada-Venegas & M. Badii (eds) Acarology XI: Proceedings of the International Congress pp. 233–240. Instituto de Biología and Faculdad de Ciencias, Universidad Nacional Autónoma de México, Sociedad Latinoamericana de Acarología: México.
[N10] Naish, D. 2010. Tetrapod Zoology: Book One. CFZ Press: Bideford (UK).