Ocadia

Ocadia is a genus of turtles in the family Geoemydidae (formerly called Bataguridae). It is sometimes included in Mauremys. It contains the following species:

O. sinensis is known to hybridize with most other Geoemydidae genera. Hybridization runs rampant in that family; while it is possible that perfectly valid species could arise this way, the other Ocadia species are apparently only known from a few specimens each, all of them purchased from a turtle dealer in Hong Kong:

The supposed species "Ocadia glyphistoma", described by Mccord & Iverson in 1994 and supposedly from southern Guangxi and northern Vietnam, is a hybrid between a male O. sinensis and a female Vietnamese pond turtle (Mauremys annamensis). This "species" seems to be naturally occurring in central Vietnam, but is occasionally also bred for the pet trade in southern Chinese turtle farms.

Philippen's striped turtle ("Ocadia philippeni"), described by Mccord & Iverson in 1992 and said to occur on Hainan, also proved to be a hybrid, between a male O. sinensis and a female Cuora trifasciata. It is not proven but likely that this "species" also originates from both the wild and is bred in farms.

In 2013, a Miocene Japanese fossil species of the same genus was described, Ocadia tanegashimensis Takahashi & al., which adds itself to the already known Pleistocene O. nipponica, from the same country.