IDNAME urn:idName:fossilplants.info:genus:74CD4796-E33D-B7B7-EEB2-45F9F7212DF8 genus
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Reyispermum

Genus Reyispermum Friis, P.R. Crane, K. R. Peders. Foss. Impr., 74(1-2): 144. 31 Aug 2018
Name
Reyispermum
Rank
Genus
Authors (Pub.)
Friis E. M. Crane P. R. Pedersen K. R.  
Publication
Extinct taxa of exotestal seeds close to Austrobaileyales and Nymphaeales from the Early Cretaceous of Portugal [2018/8]
Journal
Fossil Imprint
Volume
74
Issue
1-2
Page number
144
Year
2018

Parent Taxon
[Class] Magnoliopsida
Fossil Status
seeds

Type
Reyispermum parvum
Diagnosis
Isolated seeds occurring singly. Seeds tiny, anatropous, bitegmic and exotestal. Seeds bilaterally symmetrical with dorsiventral plane of symmetry. Seed surface smooth without longitudinal ridges. Raphal region distinct, seen externally as a slightly raised rounded ridge that extends from the hilum to the chalazal end opposite the micropyle. Hilum and micropyle separated by a moderate zone of testal sclerenchyma. Hilar scar small, circular without a rim. Micropyle formed by the inner integument (tegmen) and marked on the seed surface by a transverse slit through the outer integument (testa) adjacent to hilar scar. Testa formed from an outer layer (exotesta) of palisade-shaped sclerenchyma cells and an inner thin layer of thin-walled parenchyma cells (mesotesta/endotesta). Testa bulging below hilum. Palisade-shaped cells of exotesta with evenly thickened anticlinal walls and a straight lumen. Anticlinal walls of exotestal cells strongly undulate toward the inside and toward the outside, resulting in stellate-undulate facets and a jigsaw puzzle-like pattern on the seed surface except in the micropylar region where the anticlinal walls are straight and the outer facets polygonal. Tegmen thin.


Links by genus

Species
Reyispermum parvum

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