Kempia longicolpites E.M.FRIIS, P.R.CRANE et K.R.PEDERSEN, 2019

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 : 219-220

Kempia longicolpites E.M.FRIIS, P.R.CRANE et K.R.PEDERSEN sp. nov.

Text-fig. 43a–f

H o l o t y p e. Designated here. S105018 (Torres Vedras sample 44; figured Text-fig. 43a–f ).

P l a n t F o s s i l N a m e s R e g i s t r y N u m b e r.

PFN000480 (for new species).

R e p o s i t o r y. Palaeobotanical Collections , Department of Palaeobiology, the Swedish Museum of Natural History, Stockholm, Sweden .

E t y m o l o g y. From Latin: longus and colpus referring to very long colpus of the pollen grains.

T y p e l o c a l i t y. Torres Vedras (NE of Forte de

Forca; 39°06′13″ N, 9°14′47″ W).

T y p e s t r a t u m a n d a g e. Lower member of the Almargem Formation; Early Cretaceous (late Barremianearly Aptian).

D i a g n o s i s. As for the genus.

D i m e n s i o n s. Length of anther: 0.6 mm; width of anther: 0.25 mm. Length of pollen grains: about 11 µm.

D e s c r i p t i o n a n d r e m a r k s. Kempia longicolpites is based on a single stamen fragment from Torres Vedras that has a dithecate, tetrasporangiate, anther containing abundant pollen. The species is also known from two adhering stamens with tetrasporangiate anthers from the Catefica locality (S101208). The anther is narrowly elliptical ( Text-fig. 43a ). Pollen grains are small, almost circular in equatorial outline, and monocolpate. They were figured in an earlier publication as Pollen type D.6 ( Friis et al. 1999). The colpus extends beyond the full length of the grains, but does not divide the grain into two halves. The exine is semitectate-reticulate and columellate ( Text-fig. 43b–d ). The reticulum is heterobrochate with larger, irregular lumina and smaller angular lumina. The muri are smooth with a slightly rounded profile and occasional open ends ( Text-fig. 43e ). The muri are supported by short, scattered columellae that loosen very easily from the foot layer ( Text-fig. 43e, f ). The foot layer is thicker than the reticulum and columellae, and the endexine is well-developed only under the aperture (seen in the Catefica specimen). The colpus margin is distinct, with the reticulum continuing to the colpus margin, which is clearly delimited by the continuing marginal muri.

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. Other than the specimens from Torres Vedras and Catefica, Kempia longicolpites has not been encountered in any other mesofossil flora in Portugal. The systematic affinity of the new taxon among non-eudicot angiosperms is not known.

Figures

Text-fig. 43. Scanning electron microscope (SEM) images of monocolpate pollen of Kempia longicolpites gen. et sp. nov. from a fragmentary stamen; Torres Vedras locality, Portugal. a) Holotype; stamen fragment showing elongated pollen sacs that yielded the pollen in this Text-figure; b) Pollen grains showing the very long distal aperture and loosely attached reticulum; c, d) Pollen grains showing the very long, clearly defined distal aperture that extends around the ends of the grain; e) Reticulum in nonapertural region showing the smooth muri loosely attached to the smooth surface of the foot layer by short columellae; f) Internal view of reticulum showing the short columellae loosened from the foot layer. Specimen, TV44-S105018 (holotype). Scale bars 300 Μm (a), 30 Μm (b), 6 Μm (c, d), 3 Μm (e, f).