Teebacia hughesii 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 : 225

Teebacia hughesii E.M.FRIIS, P.R.CRANE et K.R.PEDERSEN sp. nov.

Text-fig. 46a–f

H o l o t y p e. Designated here. S136666 (Torres Vedras sample 44; figured Text-fig. 46a, d, e ).

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.

PFN000486 (for new species).

P a r a t y p e s. Designated here. S105017, S136665, S136667, S136670, S136674, S136675, S137915, S137916, S149206, S149207, S174560 (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. In honor of the British palynologist Norman F. Hughes in recognition of his important contribution to Cretaceous palynology and studies of angiosperm evolution.

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: 0.45 mm; width of anther: 0.18 mm. Length of pollen grains: about 18 µm.

D e s c r i p t i o n a n d r e m a r k s. Teebacia hughesii is based on many isolated anthers with pollen in situ. The anthers are narrowly elliptical in outline, dithecate and tetrasporangiate ( Text-fig. 46a ). Anthers and pollen were briefly described and illustrated earlier ( Friis et al. 2010a, b), but not formally named. Pollen grains found in situ within the anthers are small, about 18 µm long, almost circular in equatorial outline and monocolpate. The colpus is long extending for the full length of the grain. The exine is semitectate-reticulate and columellate ( Text-fig. 46e, f ). The reticulum is coarse, heterobrochate with lumina of various sizes ( Text-fig. 46b–f ). The muri have a rounded profile and on their upper side they are ornamented with densely spaced, narrow, transverse ridges ( Text-fig. 46c, d ). The underside of the muri is finely granular ( Text-fig. 46b ). The muri are supported by long, scattered columellae with a granular surface ( Text-fig. 46c ). The colpus margin is distinctly delimited by fused marginal muri ( Text-fig. 46e, f ). Orbicules are densely distributed on the inner surface of the anther wall and are also scattered among pollen grains. The orbicules are small, spherical with a shallow depression ( Text-fig. 46d ).

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. Pollen referable to Teebacia has also been recorded from the Vale de Água mesofossil flora with three different types , probably belonging to three different species. These three different types were described and illustrated as Pollen Type I.1, I.2 and I.3 ( Friis et al. 1999). They are all smaller than the Torres Vedras specimens ( I.1: 13–14 µm; I.2: 12–14 µm; I.3: 10–11 µm) and differ in having transverse ridges that are coarser. Grains of type I.3 are found in situ in an anther with larger, tooth-like orbicules different from the small spherical orbicules that line the inner anther walls of Teebacia hughesii .

Similar pollen are also reported from many palynofloras (see Comments on the genus) and have been referred to several different species. Pollen from the Barremian of southern England referred to as CfA Barremian- teebac (Hughes 1994) and Retisulc-Cand(Teebac) ( Hughes et al. 1979) has very fine transverse ridges similar to those of the Torres Vedras specimens.

Figures

Text-fig. 46. Scanning electron microscope (SEM) images of monocolpate pollen of Teebacia hughesii gen. et sp. nov. pollen from a stamen fragment; Torres Vedras locality, Portugal. a) Holotype; stamen fragment showing elongated pollen sacs that yielded the pollen in this Text-figure (d, e); b) Detail of detached reticulum showing inner surface of muri and scattered columellae; note the finely granular covering of the muri and columellae; c, d) Detail of reticulum showing the outer surface of muri with supratectal ornamentation of narrow ridges; note orbicules attached to the reticulum (d); e, f) Pollen grains showing loose, beaded, reticulum with long columellae; note continuous muri bordering the apertures and densely spaced minute orbicules lining the inner surface of the anther wall (e, arrowheads). Specimens, TV44-S136666 (holotype; a, d, e), TV44-S149207 (b, c, f). Scale bars 300 Μm (a), 6 Μm (e, f), 3 Μm (b), 1.5 Μm (c), 1.2 Μm (d).