- Who
- shrewish short-tailed opossum Monodelphis sorex
- Where
- Brazil ()
- When
The mammal that has most nipples (mammae) is the female of the shrewish short-tailed opossum Monodelphis sorex, which has up to 27. Despite such a large number, however, this South American marsupial is itself tiny, with a head-and-body length of only 11–13 cm, a tail length of 6.5–8.5 cm, and a weight of just 48 g. It is native to humid coastal Atlantic rainforests in southeastern Brazil, southern Paraguay and northeastern Argentina.
