Piercipollis sp. 2

Friis, Else Marie, Crane, Peter R. & Pedersen, Kaj Raunsgaard, 2019, The Early Cretaceous Mesofossil Flora Of Torres Vedras (Ne Of Forte Da Forca), Portugal: A Palaeofloristic Analysis Of An Early Angiosperm Community, Fossil Imprint 75 (2), pp. 153-257 : 218

Piercipollis sp. 2

Text-fig. 42d–f

D e s c r i p t i o n a n d r e m a r k s. Piercipollis sp. 2 is based on isolated pollen grains that occur in a coprolite with other kinds of pollen. Pollen grains of Piercipollis sp. 2 are small, about 12–13 µm in diameter, and monocolpate. The colpus is long, extending to the equator. The exine is semitectate-reticulate and columellate ( Text-fig. 42d–f ). The reticulum is coarse, homobrochate, with lumina up to about 0.15 µm in diameter that have polygonal to rounded irregular outlines ( Text-fig. 42f ). The muri are smooth with slightly rounded profiles and are supported by long scattered columellae. The colpus has a distinct margin formed by the continuing marginal muri. The reticulum detaches easily from the foot layer and the body of the grain delimited by the foot-layer is much smaller than the reticulum ( Text-fig. 42f ).

A f f i n i t y a n d o t h e r o c c u r r e n c e s. Similar grains have not been observed from other mesofossil floras in Portugal.

Figures

Text-fig. 42. Scanning electron microscope (SEM) images of monocolpate pollen of Piercipollis sp. 1 (a–c) from an isolated anther and Piercipollis sp. 2 (d–f) from a coprolite (not shown); Torres Vedras locality, Portugal. a) Narrow elongate anther that yielded the pollen in (b) and (c); b) Distal view of pollen grain showing well-developed reticulum that is only loosely attached to the foot layer; note the smooth foot layer (arrowhead) of a grain from which the reticulum has become detached; c) Reticulum showing the smooth muri and long columellae that are mostly detached from the foot layer; d–f) Pollen grains in distal (d, e), and lateral views (f) showing the very long colpus and the well-developed reticulum only loosely attached to the smooth surface of the foot layer; note the main body of the grains (foot layer) does not fill out the whole space of the reticulum (f). Specimens, TV44-S148218 (a–c), TV142-S170216 (d–f). Scale bars 300 Μm (a), 6 Μm (b, d–f), 3 Μm (c).