Palissya

This article is about extinct conifer. For the angiosperm with a junior synonym of the same name, see Necepsia.

Palissya is an extinct form genus of female (ovule-bearing) conifer cones, known from the Late Triassic (Rhaetian) to the Early Cretaceous (Aptian). The cone of Palissya is noted for its unusual catkin-like construction: Slender bracts (modified leaves) are rigidly attached in a helical pattern around a tall woody core. The adaxial (upper) surface of each bract bears two parallel rows of ovules which are encased in cup-like structures formed by scales. The seeds are thin-walled and were likely only viable for a short period of time, meaning that they were probably adapted to wind dispersal.^[1][2]

Palissya Temporal range: Rhaetian–Aptian PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Gymnospermae
Division:	Pinophyta
Class:	Pinopsida
Order:	†Palissyales
Family:	†Palissyaceae
Genus:	†Palissya Endlicher, 1847
Species
See text

Palissya has been considered in some aspects to be similar to some Paleozoic Voltziales, as well as Taxaceae and Podocarpaceae. Most leaves assigned to the genus do not belong to the same plant as the conifer cone. Palissya specimens from the Middle Jurassic of Yorkshire are associated with Elatocladus-like leaves. Several Australasian species with fragile cones were referred to the separate genus Knezourocarpon,^[2] though some were later moved back into Palissya.^[1] Other related cone genera include Stachyotaxus, Metridiostrobus, and Compsostrobus, all from the Late Triassic of the Northern Hemisphere.^[1][2]

True specimens of Palissya first appeared in the Northern Hemisphere during the latest Triassic (Rhaetian) and spread to Eastern Gondwana (modern Australia, New Zealand, and Antarctica) during the Middle Jurassic. The youngest known records of Palissya in the Northern Hemisphere are from the Middle Jurassic, but Palissya persisted in Eastern Gondwana into the Early Cretaceous, with the youngest records being from the Aptian.^[1]

Species

After^[1]

Species	Authority	Country	Age
P. hunanensis	Wang 2012	China (Hunan)	Late Triassic (Rhaetian)
P. sphenolepis	(Braun 1843) Nathorst 1908 emend. Florin 1958	Germany (Franconia)  Sweden (Stabbarp)  Poland[3]  Canada[3]	Late Triassic-Early Jurassic (Rhaetian-Hettangian)
P. harrisii	C.R. Hill ex Pattemore & Rozefelds	England (Yorkshire)	Middle Jurassic (Aalenian)
P. bartrumii	Edwards 1934	New Zealand	Middle Jurassic (Callovian) ?Late Jurassic (?Tithonian)
P. elegans	Parris et al. 1995	Australia (Victoria)	Early Cretaceous (Valanginian)
P. tillackiorum	Pattemore & Rozefelds, 2019	Australia (Queensland)	Early Cretaceous (Valanginian)
Palissya sp. (Koonwarra)	N/A	Australia (Victoria)	Early Cretaceous (Aptian)
P. antarctica	Cantrill 2000	Antarctica (Antarctic Peninsula)	Early Cretaceous (Aptian)

References

1. Pattemore, Gary A.; Rozefelds, Andrew C. (2019-12-01). "Palissya – absolutely incomprehensible or surprisingly interpretable: a new morphological model, affiliations and phylogenetic insights". Acta Palaeobotanica. 59 (2): 181–214. doi:10.2478/acpa-2019-0015. ISSN 2082-0259.
2. Pattemore, G.A.; Rigby, J.F.; Playford, G. (2014). "Palissya: A global review and reassessment of Eastern Gondwanan material". Review of Palaeobotany and Palynology. 210: 50–61. Bibcode:2014RPaPa.210...50P. doi:10.1016/j.revpalbo.2014.08.002.
3. Van Konijnenburg-Van Cittert, Johanna H.A.; Pott, Christian; Schmeißner, Stefan; Dütsch, Günter; Kustatscher, Evelyn (2021-05-01). "The Rhaetian flora of Wüstenwelsberg, Bavaria, Germany: Description of selected gymnosperms (Ginkgoales, Cycadales, Coniferales) together with an ecological assessment of the locally prevailing vegetation". Review of Palaeobotany and Palynology. 288: 104398. Bibcode:2021RPaPa.28804398V. doi:10.1016/j.revpalbo.2021.104398. ISSN 0034-6667.