Early Cretaceous striate tricolpate pollen from the Borehole Mersa Matruh 1, North West Desert, Egypt

Abstract. Striate tricolpate pollen has been recovered from Early Cretaceous samples of the borehole Mersa Matruh 1 in the N.W. Desert of Egypt. Scanning Electron Microscope (SEM) study has revealed fine details of their exine scupture, on the basis of which four new taxa, STRIOTRI-OVAL, STRIOTRI-SMOOTHMUR, STRIOTRI-SEGMUR and STRIORET-SMOOTH, are distinguished. The stratigraphic ranges of these are discussed and they are compared with other published species. They are among the oldest striate tricolpate pollen yet described, appearing in sediments of Early Aptian age, slightly predating the first reliable records of reticulate tricolpates in the sequence studied. The lack of earlier reticulate grains is attributed to possible sample failure. There is evidence that the true first appearance of tricoplate pollen in Egypt may be late Barrenian.