Two new megaspore species from the continental Upper Cretaceous (Campanian–Maestrichtian) of the Alberta Plains

Abstract

Two previously undescribed megaspore entities, one with accompanying microspore, were observed in Upper Cretaceous rock samples collected during coal survey activities in the Plains Region of Alberta.Molaspora reticulata sp. nov. has a spheroidal body 244–398 microns (μ) in diameter with a small prominent neck. Its outer spore wall is thick and profoundly sculptured forming very narrow reticulations with extremely high muri. The spore has been found in strata of middle Campanian and middle Maestrichtian age (Late Cretaceous).Ariadnaesporites macroglebulosus sp. nov. has a spherical body, and a prominent trifolium about as long as the body diameter or slightly shorter. The megaspore central body is 224–373 μ in diameter, while that of the microspore is about 76 μ in diameter. The surface of the spore body is ornamented by extremely coarse, inflated verrucae which, in turn, bear a fine reticulate pattern. From the apex of each verruca arises a hollow filamentous process with an expanded base and usually clavate tip. The processes are about 5 μ in diameter and may exceed 2500 μ in length. This entity has been found in strata of middle Campanian (Late Cretaceous) age.