The Early Cretaceous Mesofossil Flora Of Torres Vedras (Ne Of Forte Da Forca), Portugal: A Palaeofloristic Analysis Of An Early Angiosperm Community
Author
Friis, Else Marie
Author
Crane, Peter R.
Author
Pedersen, Kaj Raunsgaard
text
Fossil Imprint
2019
2019-11-25
75
2
153
257
http://dx.doi.org/10.2478/if-2019-0013
journal article
10.2478/if-2019-0013
2533-4069
5386203
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).
Text-fig. 54. Scanning electron microscope (SEM; a–e, g, h) and synchrotron x-ray microscopy (SRXTM; f, i) images of unnamed angiosperm fruits and seeds; Torres Vedras locality, Portugal. a) Follicle sp. 1, narrow elongate follicle with sessile and decurrent stigma; b) Follicle sp. 2, broad, dehisced follicle with elongate and transverse fibers lining the locule; c) Angiosperm seed sp. 1 with thin, smooth seed coat; d) Angiosperm seed sp. 2 with verrucate seed coat; e) Angiosperm seed sp. 3 with exotestal and foveolate seed coat; f) Angiosperm seed sp. 4 with smooth seed coat; g, h) Angiosperm seed sp. 5 with raised epidermal cells forming a reticulate pattern; i) Wedge-shaped angiosperm fruit with remains of floral parts near apex. Specimens, TV43-S136726 (a), TV44-S148144 (b), TV43-S170074 (c), TV43-S136747 (d), TV43-S170073 (e), TV38-S174615 (f), TV44-S148003 (g), TV44-S148004 (h), TV43-S174685 (i). Scale bars 300 Μm (a–i).
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.