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
Reyanthus lusitanicus
E.M.FRIIS, P.R.CRANE et K.R.PEDERSEN
sp. nov.
Text-fig. 50a–j
H o l o t y p e. Designated here. S136716 (Torres Vedras sample 299; figured
Text-fig. 50a–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.
PFN000492 (for new species).
P a r a t y p e. Designated here. S136717 (Torres Vedras sample 299).
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: Lusitania for
Portugal
where the fossil was discovered.
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 flower without stalk: ca.
0.48 mm
; width of flower: ca.
0.58 mm
.
D e s c r i p t i o n a n d r e m a r k s.
Reyanthus lusitanicus
is based on a single multiparted flower and a group of detached carpels, all of which have been studied with SEM and SRXTM. The flower is borne on a stout stalk that has an associated bract (
Text-fig. 50a, b
). Below the flower is another bract with a small bud in its axil, which is probably an undeveloped flower (
Text-fig. 50b
). The outer parts the flower are abraded and tepals and stamens are poorly preserved. The number and arrangement of tepals and stamens is uncertain. Small dorsiventrally flattened structures immediately outside the carpels are the probable remains of stamens, or perhaps staminodes (
Text-fig. 50e
). The tepals and stamens are each apparently arranged in a single series. The gynoecium is multicarpellate and apocarpous. It consists of about 20 carpels borne helically on a short conical receptacle (
Text-fig. 50a–f
). The carpels are crescent-shaped, slightly flattened laterally and have a straight ventral margin. The stigma is sessile, indistinct. The flower appears to be preserved at anthesis and the number of ovules is not clear. However, the detached carpels are larger and probably more mature (
Text-fig.
50g
–j
). These detached carpels are assigned to
Reyanthus lusitanicus
based on their shape, and also the anatomy of the carpel wall. They contain several ovules borne along either side of the ventral suture. None of the fossil material is sufficiently well preserved to provide information on the organization of the ovules. All floral parts contain large, spherical cells that are densely spaced throughout the tissues, which we interpret as oil cells. In the larger, isolated carpels the oil cells are embedded in the outer tissue of the carpel wall (
Text-fig. 50i, j
) and are often visible on the carpel surface or sometimes as holes in the fruit wall (
Text-fig.
50g
, h
).
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.
Reyanthus lusitanicus
is known only from the Torres Vedras locality. Taken together, the multiparted organization, the presence of oil cells and the several ovules per carpel indicate affinity with
Magnoliales
, but there is no clear relationship to a specific extant taxon.