Palissyales are an extinct order of conifers, known from the
Mesozoic
The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretace ...
. They are best known from the genus ''
Palissya'', which is found in
Laurasia and Eastern
Gondwana dating from the Late
Triassic
The Triassic ( ) is a geologic period and system (stratigraphy), system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago (Year#Abbreviations yr and ya, Mya), to the beginning of the Jurassic Period 201.36 ...
to Early
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...
. The only other confirmed genus of the family, ''
Stachyotaxus'' known from the Late Triassic of the Northern Hemisphere. The genus ''
Knezourocarpon'' from the
Jurassic
The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of ...
of Australia has also been tentatively considered a member of the order.
The cone of the best known genus ''Palissya'' is noted for its unusual construction, which is borne on a large
bract (modified leaf), and consists of two parallel rows of
ovules
In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: the ''integument'', forming its outer layer, the ''nucellus'' (or remnant of the megasporangium), and the fe ...
that run along the midline of the