Parataxospermum, Z.M.Li, 1993

Galtier, Jean, Ronchi, Ausonio & Broutin, Jean, 2011, Early Permian silicified floras from the Perdasdefogu Basin (SE Sardinia): comparison and bio-chronostratigraphic correlation with the floras of the Autun Basin (Massif central, France), Geodiversitas 33 (1), pp. 43-69 : 62-63

cf. Parataxospermum ( Fig. 9I )

Dispersed cardiocarpalean ovules of this type are the most common, occurring in about 1/10 of specimens.

They are up to 1 mm long and 6 × 5 mm wide. They are characterized by a prominent sclerotesta up to 1 mm thick composed of large thick-walled cells 50 to 200 µm in diameter gradually decreasing in size in the outermost sclerotesta and near the base of the ovule. Detailed description of these ovules will be presented in another paper but it is worth mentioning that they are most similar with ovules from Carboniferous-Permian coal balls from Shanxi Province in China described by Li (1993).

Figures

FIG. 9. — Silicified plants from the Permian of Sardinia: A, Cordaixylon sp., transverse section of a partly decorticated small stem with a solid parenchymatous pith; on the left the closely associated rachis (P) with several xylem bundles may represent a petiole of the same plant (SAR24B4L13);B, Cordaites leaves associated with Pecopteris pinnules;the broadest leaf (CC) with interfascicular scleren-