Cartorhynchus is an extinct genus of basal ichthyosauriform marine reptile that lived during the early Triassic period. Fossils have been found in eastern China and were unearthed from rocks in 2011. Those rocks were laid down as marine sediments about 248 million years ago. The only well-preserved fossil is quite complete, with only a portion of the tail missing. When alive, the creature was probably about 40 cm (16 in) long — about the size of a large lizard — and weighed about 2 kg (4.4 lb).