Lakkosia kerasata gen. et sp. nov., a permineralized megasporangiate glossopterid structure from the central Transantarctic Mountains, Antarctica

• Published in: International journal of plant sciences Vol. 171; no. 3; pp. 332 - 344
• Main Author: Ryberg, Patricia E
• Format: Journal Article
• Language: English
• Published: Chicago The University of Chicago Press 01.03.2010; University of Chicago, acting through its Press
• Subjects: Cells; Flowers & plants; fossils; Glossopteridales; Glossopteris; Lakkosia kerasata; Molecular structure; new genus; new species; paleobotany; plant morphology; Plant reproduction; Plant sciences; plant taxonomy; Tissues; Antarctica; Transantarctic Mountains; Glossopteris; megasporophyll; Antarctica; Permian; Glossopteridales; Lakkosia
• ISSN: 1058-5893; 1537-5315
• DOI: 10.1086/650156

Permineralized reproductive structures have been known from Antarctica for the past four decades. No formal descriptions have been available for this material, however, leaving a gap in our knowledge of the glossopterid clade. Lakkosia kerasata gen. et sp. nov. is a multiovulate, megasporangiate structure found in silicified peat from the Upper Permian Skaar Ridge locality in the central Transantarctic Mountains. Ovules are borne in depressions on the adaxial surface of the megasporophyll and enclosed in thin strips of tissue that arise from the sporophyll. Transfusion tissue with scalariform wall thickenings is present in the sporophyll and may have acted as storage or conducting tissue. In longitudinal sections of the ovules, the sclerotesta forms two appressed, hemispherical masses of lignified parenchyma cells, which create the micropyle. Tissue of the sarcotesta overarches these parenchymatous masses, creating a chamber above the micropyle. Lakkosia is compared to previously described permineralized glossopterid structures from Antarctica, permineralized reproductive structures from the Bowen Basin of Australia, and impression material found in Antarctica.