A palynological investigation of Toarcian to early Aalenian strata from the Blea Wyke area, Ravenscar, North Yorkshire

SUMMARY A palynological investigation of the uppermost part of the Whitby Mudstone, the Blea Wyke Sandstone and the Dogger formations (Toarcian, Hildoceras bifrons Zone to Aalenian, Leioceras opalinum Zone) exposed on the foreshore and in the cliffs of the area around Blea Wyke Point, Ravenscar, yielded thirteen dinoflagellate cyst taxa. They all appear to be biostratigraphically significant, and in this respect are superior to other associated palynomorph groups (e.g. miospores), despite being numerically subordinate. The genus Phallocysta Dörhöfer & Davies 1980 and the species P. eumekes Dörhöfer & Davies 1980 are emended. The dinoflagellate cyst floras from Blea Wyke are compared with other published accounts of similar ages. Despite the existence of several cosmopolitan taxa in the Northern hemisphere, two cyst-provinces, the North American province and the north-west European province are recognised.