Fossil remains of Quasipetalichthys have been found in the Middle Devonian, Givetian faunal stage of China.

[2] Quasipetalichthys haikouensis is considered a basal petalichthyid (though in 1978 Denison referred to it as being "aberrant"[2]).

The Haikou Formation, the only known set of rocks that has produced fossils of Quasipetalichthys, appears at the Earth's surface in south-central China.

[5][1] Other paleontological investigations into these sediments have produced spores and macrofossils from Devonian plants such as the Lycopods (classified as Lycopodophyta or Lycopsida)).

[5][6][7] These plant remains often occur alongside those of Placoderms such as Bothriolepis which implies a very near-shore or freshwater environment for this geologic formation.