It was a diverse genus known throughout western and southern Europe from the Ypresian to the Priabonian.

[1] The following species are known:[1][2] Indeterminate remains are known from the latest Eocene (Priabonian) of France and Spain; these have not been assigned to a specific species, but represent the youngest record of the genus.

[7] Morphological analyses suggest that Neochelys likely represents an ancient lineage of the Erymnochelyinae, sister to the clade composed of the South American Peltocephalus and the Malagasy Erymnochelys.

[4] The taxonomic relationships between the multiple Neochelys species remain largely unknown.

[1] A pathological Neochelys shell is known from the middle Eocene of Spain, hosting abnormalities that were previously thought to be the result of a crocodile attack.