LEAF CUTICLE ANATOMY AND THE ULTRASTRUCTURE OF GINKGOITES TICOENSIS ARCHANG. FROM THE APTIAN OF PATAGONIA

DEL FUEYO, G.; GUIGNARD, G.; LILIANA VILLAR DE SEOANE; ARCHANGELSKY, S.

INTERNATIONAL JOURNAL OF PLANT SCIENCES

UNIV CHICAGO PRESS

Lugar: Chicago; Año: 2012 p. 406 - 424

1058-5893

The leaf cuticle of the Ginkgoites ticoensis Archang. type material from the Aptian Anfiteatro de Tico´Formation in Patagonia, Argentina, is fully characterized with additional scanning and transmission electronmicroscopic observations. Many new anatomical and ultrastructural cuticular features are identified in thefour-lobed leaf of G. ticoensis: the leaf shows a hypostomatic and papillate laminae, straight and pittedanticlinal and granulate periclinal walls, actinocytic stomata with between five and seven papillate, striatesubsidiary cells, and guard cells with anticlinal smooth walls. The TEM studies on ordinary epidermal cells,papillae, subsidiary cells, and guard cells reveal general ultrastructural features of Ginkgoaceae: an outerpolylamellate layer A made with A1 and a granular inner layer A2; A1 with an upper part A1U withcontinuous and straight translucent lamellae; a lower part A1L with significantly disrupted and wavingtranslucent lamellae; and the fibrillar cuticular layer B1 as the innermost part. Ten ultrastructural charactersare detailed and ranked by the use of confidence intervals based on 30 statistical measurements. A threedimensionalreconstruction of the cuticle is also provided. Because of the anatomical and ultrastructural finedetails shown in the G. ticoensis cuticle, new elements are given to suggest its probable family affinity and toenhance the specificities of Ginkgo and Ginkgoites.