Ibrahimia vermiculata 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 : 238-240

Ibrahimia vermiculata E.M.FRIIS, P.R.CRANE et K.R.PEDERSEN sp. nov.

Text-fig. 55a–h.

H o l o t y p e. Designated here. S148019 (Torres Vedras sample 44; figured Text-fig. 55a–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.

PFN000500 (for new species).

P a r a t y p e s. Designated here. S136766-01, S136782

(Torres Vedras sample 44).

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: vermiculatus referring to the worm-shaped, winding sculptural elements.

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. Diameter of pollen grains: 15–17 µm.

D e s c r i p t i o n a n d r e m a r k s. Pollen grains of Ibrahimia vermiculata have been found in situ in two fragmentary anthers ( Text-fig. 55a, g ) and also in a coprolite that contains mainly Goczania type pollen grains. One of the anthers and its enclosed pollen ( Text-fig. 55g, h ) appears degraded, but the pollen grains are similar in size and sculpturing to those in the other anther and in the coprolite. The pollen grains are spheroidal, minute, and about 15–17 µm in diameter. They are pantoporate with about six circular pores. The exine is tectate-vermiculate with a supratectal ornamentation of conical microechinae up to about 0.9 µm long ( Text-fig. 55b–f, h ). The microechinae are not constricted at the base and have a blunt tip. The vermiculate sculpturing of the main pollen body continues into the base of the microechinae ( Text-fig. 55f ). The aperture membrane is finely granular to verrucate ( Text-fig. 55e, f ). Orbicules were not observed.

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. Ibrahimia vermiculata has so far only been recorded from the Torres Vedras mesofossil floras.However, other kinds of pantoporate pollen are known from other Portuguese mesofossil floras. Pantoporate reticulate pollen grains of possible chloranthoid affinity are known from Famalicão ( Friis et al. 1999) and pantoporate reticulate pollen grains of possible araceous affinity are known from the Vila Verde 2 locality ( Friis et al. 2010b). Microechinate and pantoporate pollen grains have also been found in situ in flowers of Paisia pantoporata from the Catefica locality that are probably of ranunculalean affinity ( Friis et al. 2018e). The Ibrahimia grains are closely similar to those from the Paisia flowers, and they may also be systematically closely related. However, the Paisia grains are smaller, lack the vermiculate tectal sculpturing and the spines are constricted at their bases.

Figures

Text-fig. 55. Scanning electron microscope (SEM) images of stamen fragments and pollen of Ibrahimia verminculata (a–h) and unnamed pantoporate pollen from pollen clump (i); Torres Vedras locality, Portugal. a) Holotype; stamen fragment that yielded the pollen in (b–f); b–f) Pantoporate pollen grains with vermiculate tectum and regularly spaced microechinate and pores with verrucate aperture membranes; g) Stamen fragment that yielded the pollen in (h); h) Abraded pantoporate pollen with vermiculate tectum and regularly spaced microechinate; i) Pantoporate pollen from coprolite with microreticulate-foveolate tectum and verrucate aperture membranes. Specimens, TV44-S148019 (holotype; a–f), TV44- S136782 (g, h), TV142-S170216 (i). Scale bars 300 Μm (a, g), 15 Μm (b), 6 Μm (d, e, h, i), 1.5 Μm (c, f).