Morphology and occurrence of the Normapolles pollen genus Papillopollis in the cretaceous of Portugal

Abstract

Rationalization of the taxonomy of pollen grains referable to Papillopollis has been necessary so that the majority of specimens encountered in the Senonian succession of Portugal can be identified. Revised diagnoses are provided for P. aradaensis Kedves & Pittau, P. aveiroensis Kedves & Pittau, P. minimalis Pacltová & Krutzsch, P. rugulatus Kedves & Pittau and P. santonius Pacltová & Krutzsch; one new species, P. barbosae, is erected. The degree of morphological variation allowed for these species is greater than in previous descriptions of forms of Papillopollis and enables the removal of seventeen other taxa which lack reliable distinguishing characters by placing them in synonymy.

The sculpture of the pollen grains described ranges from essentially granulate to minutely papillate. The sexine at the poles is typically fissured or reduced to small granular or papillate masses or bodies, but can be absent altogether. These areas of modified exine may have had a harmomegathic function. Thin sections of several species reveal that their wall structure is similar, both adjacent to the apertures and elsewhere. It resembles most closely the composition of the exine of grains produced by extant members of the wind‐pollinated Juglandales‐Myricales complex.

Hitherto, most records of Papillopollis species, all of which are European, are from strata dated as Santonian and/or Campanian. In Portugal, where they are particularly varied, they are also common in deposits that are likely to be early Maastrichtian in age.