Canrightia elongata 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 : 179-183

Canrightia elongata E.M.FRIIS, P.R.CRANE et K.R.PEDERSEN sp. nov.

Text-fig. 17a–g

H o l o t y p e. Designated here. S174100 (Torres Vedras sample 38; figured Text-fig. 17a–g ).

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.

PFN000456 (for new species).

exotestal seeds resembling Gastonispermum antiquum sp. nov. showing poorly preserved thin fruit wall (f, g) and seed with a smooth surface (h). Specimens, TV43 - S136738 (a, d) , TV43 - S136736 (holotype; b) , TV43 - S136737 (c) , TV298 - S174629 (e) , TV43 - S136748 (f, h) , TV43 - S136749 (g) . Scale bars 300 Μm (a, b, f, g), 200 Μm (e), 30 Μm (c, d, h).

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: elongatus referring to elongate shape of the fruit and seeds.

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).

S p e c i f i c d i a g n o s i s. Fruit elongate, obovoid with a short, conical hypanthium. Stigmatic area sessile, indistinct. Ovules pendant, orthotropous to semiorthotropous, bitegmic, endotestal-endotegmic; testa comprising two cell layers; exotesta thin; endotesta with cubic to palisade-shaped crystal cells and fibrous infillings; tegmen three cell layers thick; exotegmen of elongated fibrous cells, mesotegmen with cubic thin-walled cells and endotegmen with large, palisade-shaped cells that form an endothelium; endotegmen cells with infilling of tannin. Fruit a sessile berry with three seeds. Fruit wall with densely spaced cavities from presumed oil cells.

D i s t i n g u i s h i n g f e a t u r e s. Canrightia elongata is distinguished from the only other species of the genus, Canrightia resinifera E.M.FRIIS et K.R.PEDERSEN , by its more elongated shape and shorter, conical, hypanthium.

D i m e n s i o n s. Length of fruit: 1.2 mm; width of fruit:

0.65 mm.

D e s c r i p t i o n a n d r e m a r k s. The new species is based on a single fruit, containing three seeds, which has been studied using SEM and SRXTM. The fruit is closely similar to fruits of Canrightia resinifera described from other localities in Portugal, but differs especially in the shape of the elongated fruit and the short conical hypanthium. The hypanthium is short, about one quarter the length of the fruit ( Text-fig. 17a–c ), and the fruit as well as the hypanthium is subtended by a short bract ( Text-fig. 17c ). The hypanthium has four radially arranged triangular lobes that we interpret as reduced tepals. Each lobe subtends a scar interpreted as staminal scar, and the four scars suggest an androecium composed of four stamens ( Text-fig. 17c ).

Cellular details of the fruit wall are not preserved, except for densely spaced circular openings near the surface of the fruit ( Text-fig. 17a–f ) that we interpret as empty oil cells. The fruit contains three bitegmic, orthotropous and pendant seeds. The outer layer of the testa (exotesta) is thin, with no cellular details preserved, and is difficult to distinguish from the fruit wall. The inner layer of testa (endotesta) is distinct, one cell layer deep and consists of palisade-shaped cells with a fibrous infilling that contains the angular imprints of crystals. These endotesta cells are similar to the endotesta cells of Canrightia resinifera . The outer surface of endotesta appears almost smooth without depressions or longitudinal ridges.

One of the seeds has a well-developed inner layer of the tegmen (endothelium) while the two other seeds have remains of nutritive tissue and one contains remains of an embryo at the micropylar end. This suggests that two of the seeds were close to maturity while the third may have been aborted.

Two isolated seeds ( Text-fig. 17h, i ) that have a crystalliferous seed coat ( Text-fig. 17j ) may be seeds of Canrightia elongata or Canrightia sp. These seeds are very similar to seeds of Canrightia resinifera , but the larger crystals in the endotesta are scattered and surrounded by smaller crystals, whereas in C. resinifera the large crystals are densely arranged in the outer part of endotesta.

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. Canrightia is an extinct genus closely related to the clade comprising extant Ascarina J.R.FORST. et G.FORST. , Chloranthus SW. and Sarcandra GARDNER , among extant Chloranthaceae ( Friis and Pedersen 2011) . Canrightia elongata is currently known only from the Torres Vedras locality. The only other species of the genus, Canrightia resinifera is known based on numerous well-preserved specimens from the Arazede, Buarcos, Catefica, Famalicão and Vale de Água localities ( Friis and Pedersen 2011).

Figures

Text-fig. 17. Scanning electron microscope (SEM) and synchrotron radiation X-ray tomographic microscopy (SRXTM) images of a fruit of Canrightia elongata sp. nov. (a–g) and isolated Canrightia-like seeds (h–j); Torres Vedras locality, Portugal. a–c) Holotype; fruit in lateral view showing four fused tepals at the base (c, upper arrowheads) and prominent cavities in the fruit wall formed by scattered oil bodies and possible subtending bract (c, lower arrowhead); d) Transverse section (SRXTM orthoslice xy1510) through the fruit showing three locules, one with the remains of the endothelium (top left, 1), the other two (2, 3) with remains of presumed endosperm tissue; note that the locule to the right (3) is crushed; e, f) Radial longitudinal (e; SRXTM orthoslice xz1212)