Stratigraphic distribution of species of the megaspore genus Minerisporites in North America

Sedimentary successions and palynoevent stratigraphy from the non-marine Lower Cretaceous to the marine Upper Cretaceous of the Nuussuaq Basin, West Greenland

“…The lower 80 m of the section are offset from the upper 40 m. The composite section was described as the Kome Formation and used as the type section of the redefined Kome Formation (Dam et al, 2009, their fig. The new record of a few Plicatella bifurcata suggests an Aptian or Albian age (according to Singh, 1971;Brideaux and McIntyre, 1975) and a megaspore species of the genus Minerisporites may be M. venustus, suggesting a middle or late Albian age (according to Singh, 1971 andTschudy, 1976). The present study has re-examined the palynological assemblages of 27 samples from the lower 80 m section and confirms a dominance of non-marine organic material and rare to common spores, pollen, and rare megaspores, whereas no dinoflagellate cysts (dinocysts) were recorded.…”

The Livingston Formation in the Madison Range of southwestern Montana

“…The key species are Pseudoplicapollis newmanii, a form that appeared in the earliest Campanian and for which the earliest Campanian palynomorph biozone is named (Nichols and others, 1982), and Aquilapollenites sp., a previously undescribed form. The species of Aquilapollenites present has not been reported from middle or late Campanian palynomorph biozones, and none of the other species of palynomorphs that characterize the middle or late Campanian are present in the assemblage from sample locality G. The megaspore Minerisporites pseudorichardsonii has been reported previously from the Santonian in Wyoming and the lower Campanian in Montana (Tschudy, 1976). Thus the palynological evidence indicates that the lower member of the Livingston is early Campanian in age, and it suggests that the unit dates from near the boundary of the P. newmanii and A. senonicus biozones (estimated absolute age about 81 m.y.…”

Mid-Cretaceous megaspore floras from Maryland, USA

“…The absence of a deep notch in the margo at the pole and lack of compound reticulum exclude the Elk Neck specimens from Minerisporites dissimilis Tschudy, 1976 with which they otherwise are very similar, and of similar age. These megaspores most closely resemble Minerisporites “ dissimilis ” from the Cenomanian illustrated by Singh (1983, pl.…”

“…Although of botanical interest, megaspores have not been used widely for biostratigraphic purposes (but see, e.g., Fulgewicz, 1973, 1979, 1980, and Marcinkiewicz, 1971, 1976, 1992, for Triassic and Jurassic usage), in part because of the large volume of sediment required to adequately characterize diversity as compared to much smaller pollen and spores. Nevertheless, Tschudy (1976) championed the potential utility of megaspores for biostratigraphic zonation in combination with palynomorphs, if only widespread, routine sampling would be conducted. This is the third in a series of contributions (Lupia, 2004, 2011) aimed at documenting megaspore floras through time along the East and Gulf coasts of North America.…”

“…However, no one has described similarly complete Albian and Cenomanian megaspore floras from the East Coast. Isolated megaspores from the Albian and Cenomanian have been identified based mainly on specimens appearing in palynological preparations from the East and Gulf coasts by Kimyai (1966), Paden Phillips and Felix (1971), Wolfe and Pakiser (1971), and Tschudy (1975); and from elsewhere in North America by Potter (1963), Ellis and Tschudy (1964), Hedlund (1966), Agasie (1969), Playford (1971), Bergad (1973), Romans (1975), Tschudy (1976), Wingate (1980), Zippi and Bajc (1990), Ravn (1995), Ravn and Witzke (1995), Scott and Stea (2002), and Hu et al (2008).…”