Graverobber Shrewv
Among the ambling roundshell shrewvs and slow, awkward on land tail-walking mudhoppers clambering out of Raptor River, there is already an aquatic equivalent of a defiler of graves. As the roundshell shrewvs began to bud off from each other, a glitch in the genetic code of some roundshell shrewvs in Raptor River occurred. Their offspring never gained shells, and thus had to find them to survive among their compatriots. Thus gave rise to the graverobber shrewv.
Aside from the lack of shell, it is not particularly different in biology when compared to its ancestor, but it has some biological differences to cope with its freshwater habitat. Similarly to its close ancestor, it has a simple osmoregulation system that, in comparison to its ancestor, is somewhat more efficient. They go about their lives as any other shrewv would, filtering detritus and chunks of dead things using their mouth psuedopods and exchanging genetic material with others of their kin to create new individuals. They have noticeably lost the ability to filter microbes. However, its lack of shell leaves it vulnerable, so it must find other ways of being protected, giving the graverobber shrewv its name. It typically uses the shells of long dead Wright nautstars as homes, typically foraging for them until a suitable shell is found. Once an individual has fully settled in its new shell, it remains in that shell for life, with the young leaving to find shells that fit them. These preferences change as the shrewv matures, with larger and larger shells being chosen as they grow.