Canrightia foveolata E. M. FRIIS, P. R. CRANE, K. R. PEDERSEN, M. M. MENDES et J. KVACEK 2022, sp. nov.
Creators: name: Friis, Else Marie
name: Crane, Peter R.
name: Pedersen, Kaj Raunsgaard
name: Mendes, Mário Miguel
name: Kvaček, Jiří
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Chloranthales
Chloranthaceae
Canrightia
Canrightia foveolata

description: Canrightia foveolata E.M.FRIIS, P.R.CRANE, K.R.PEDERSEN, M.M.MENDES et J.KVAČEK sp. nov.
Text-figs 3a–f, 4a–i
Holotype. S174249 (Catefica sample 49; figured Text-fig. 3a–f).
Plant Fossil Names Registry Number.
PFN002785 (for new species).
Paratypes. S175179, S265998, S266057, S266107 (Catefica sample 49), S266042 (Catefica sample 154), S175178 (Catefica sample 242).
Repository. Palaeobotanical Collections, Department of Palaeobiology, Swedish Museum of Natural History, Stockholm, Sweden.
Etymology. From Latin: fovea (pit) referring to the densely pitted surface of the endotesta.
Type locality. Catefica (39° 03ʹ 30ʺ N; 09°14ʹ 30ʺ W), between the villages of Catefica and Mugideira, about 4 km south of Torres Vedras, Portugal.
Type stratum and age. Almargem Formation, Early Cretaceous (Aptian-early Albian).
D i a g n o s i s. Fruit obovoid with a broad hypanthium and two pendent seeds. Perianth of six tepals. Contact surface between the two seeds flat; external surface rounded. Crystals evenly distributed in the cells of the endotesta. Surface of endotesta foveolate with shallow foveae arranged in more than 30 closely packed longitudinal rows. Fruit wall particularly thick apically over the seeds.
Distinguishing features. The new species is assigned to the extinct genus Canrightia based on the berry-like fruit with pendent, orthotropous seeds that have an endotestal-endotegmic seed coat and a crystalliferous endotesta. Canrightia foveolata is distinguished from C. resinifera (see above), and from C. elongata from the Torres Vedras mesofossil flora (Friis et al. 2019a), mainly by the densely pitted and grooved surface of the endotesta. Seeds of C. foveolata also have crystals that are of more or less of similar size and that are evenly distributed in the endotestal cells, whereas in C. resinifera and C. elongata larger crystals are concentrated close to the outer surface of endotesta. Canrightia foveolata is also two-seeded, as are most specimens of C. resinifera from the Famalicão locality, while fruits of C. resinifera from the Catefica locality typically have three to five seeds and C. elongata has three seeds.
Canrightia foveolata is further distinguished from the two other species of Canrightia by the well-developed soft tissue of the fruit wall above the seeds. Canrightia foveolata may also be distinguished from the two other species by the larger number of perianth parts, but as the perianth is known for only one specimen of C. foveolata, and only a few specimens of C. resinifera, the range of tepal numbers in Canrightia is not fully established.
A pitted surface of the endotesta is also present in seeds of Canrightiopsis E.M.FRIIS, G.W.GRIMM, M.M.MENDES et K.R.PEDERSEN and Kvacekispermum E.M.FRIIS, P.R.CRANE et K.R.PEDERSEN, two other extinct genera of chloranthoid affinity (Friis et al. 2015a, 2018b), but both of these genera have one-seeded fruits and a much thicker endotestal seed coat.
Dimensions. Length of fruit: 1.7 mm; maximum width of fruit: 1.6 mm; length of seed: 0.85–1.05 mm; maximum width of seed: 0.6–0.9 mm.
Description and remarks. The new species is based on a single fruit, containing two seeds (Text-fig. 3a–f). There are also several isolated seeds (Text-fig. 4a–i). The fruit and two of the isolated seeds were studied using SRXTM. The fruit is partly abraded, and although the stigmatic region is missing, the fruit is otherwise well preserved in its apical part. There is a swollen rim about halfway up the fruit with six, small poorly developed tepals that are best preserved on one side of the fruit (Text-fig. 3a). Five vascular bundles are preserved in the hypanthium, each extending to a tepal and their symmetry indicates that a sixth bundle has been lost where the fruit wall is abraded (Text-fig. 3d). The fruit wall is particularly thick in the region above the seeds and consists mainly of isodiametric cells (Text-fig. 3a–c).
The seeds are broadly elliptical, crescent-shaped in lateral view, slightly pointed at the micropylar end and rounded at the chalazal end (Text-figs 3b, 4a–d, f). Where the two seeds meet, their faces are flattened, but with a prominent chalaza that projects towards the face where the seeds meet (Textfig. 4b, d). The opposite faces are rounded (Text-figs 3c, d, 4b, c, e). In the isolated seeds, the outer cells of the seed coat are abraded exposing the surface of the endotesta, which is characterized by numerous small pits arranged in more than 30 shallow, closely-spaced, longitudinal grooves (Text-fig. 4a–d).
In the fruit the exotesta of the seeds is partly preserved and consists of thick-walled, isodiametric cells. The endotesta is thin (about 30 µm) in the region between the two seeds, but thicker (about 55 µm) in the chalazal region and toward the outer surfaces (Text-fig. 3c, e, f). The exotesta is so tightly appressed to the tissue of the fruit wall that the two tissues are sometimes difficult to delimit. The endotesta consists of palisade-shaped cells that are infilled with fibrous material in which there are abundant casts of cubic crystals. The casts of these crystals are distributed more or less evenly within the cells (Text-figs 3f, 4e–i).
The inner integument is three cell layers thick. It consists of an outer epidermis, a middle layer of thick-walled and slightly longitudinally elongated cells, and an inner epidermis that develops into an endothelium of thin-walled and radially elongated cells (Text-figs 3c, d, 4e, f, h).
The stigmatic area is not preserved and no pollen was observed on the surface of the fruit.
Affinity and other occurrences. The relationships of Canrightia foveolata, as for Canrightia resinifera, arelikelyclosetothebaseofextantChloranthaceae (see above). Canrightia foveolata is currently known only from the Catefica locality.
description: Published as part of Friis, Else Marie, Crane, Peter R., Pedersen, Kaj Raunsgaard, Mendes, Mário Miguel & Kvaček, Jiří, 2022, The Early Cretaceous Mesofossil Flora Of Catefica, Portugal: Angiosperms, pp. 341-424 in Fossil Imprint 78 (2) on pages 347-349, DOI: 10.37520/fi.2022.016, http://zenodo.org/record/7522801