Upper Permian and Lower Triassic palynomorphs from eastern Yunnan, China

Abstract

In eastern Yunnan the Upper Permian Lungtan and Changhsing Formations and the Lower Triassic Kayitou Formation each contain a characteristic assemblage of spores and pollen.The Torispora gigantea – Patellisporites meishanensis assemblage in the Lungtan Formation contains abundant pteridophyte and pteridosperm spores and few gymnosperm pollen. Some genera are known from the Carboniferous and Lower Permian of Europe but most are Cathaysian. The Yunnanospora radiata – Gardenasporites assemblage in the Changhsing Formation has a Paleozoic aspect but characteristic Mesozoic genera and species occur. The Lundbladispora–Aratrisporites–Pteruchipollenites assemblage in the Kayitou Formation contains numerous pteridophyte and pteriodosperm spores and gymnosperm pollen; some Paleozoic genera occur (Crassispora, Lycospora?, Stellisporites, Thymospora, Torispora, Triparites, Triquitrites, and Waltzispora), but Mesozoic genera predominate. Thirty metres above the base of the Kayitou Formation gymnosperm pollen, especially that of conifers, becomes dominant.It is suggested that the Carboniferous and Lower Permian species in the Changhsing Formation and the Paleozoic genera in the Kayitou Formation are not reworked but are indigenous and that the composition of the resulting microflora reflects the parent flora. The presence of this microflora in Lower Triassic rocks suggests that, at least locally, sedimentation was essentially continuous across the Permian–Triassic boundary.