In North America, Edward Drinker Cope found another mosasaur in 1869, but had identified it as Mosasaurus.

[1][2] In 1999, Holmes and colleagues described an incomplete specimen of Plioplatecarpus from an early Maastrichtian non-marine deposit, suggesting that this genus might have entered freshwater and estuarine habitats.

[6][7] The eyes of Plioplatecarpus are proportionally larger than those of many mosasaur genera, although the skull is relatively short.

The larger eyes may be an adaptation to low light conditions like those found in deeper water.

The broad distribution of fossil remains in both North America and Europe suggest that it would have been an open ocean predator.