6533b7d8fe1ef96bd126b801
RESEARCH PRODUCT
Micromorphological approach to the systematics of Mediterranean Isoëtes species (Isoëtaceae, Lycopodiophyta): analysis of the megaspore surface
Rosario SchicchiGiuseppe BazanAngelo Troiasubject
SystematicsbiologyIsoetes histrixSettore BIO/02 - Botanica SistematicaPlant Sciencebiology.organism_classificationSettore BIO/01 - Botanica GeneraleTaxonSEM energy-dispersive X-ray spectroscopy (EDS) Sicily siliceous coating Isoetes Isoëtes duriei Isoëtes histrix Isoëtes sicula Isoëtes todaroana Isoëtes velataIsoetesBotanyIsoetaceaeTaxonomy (biology)LycopodiophytaMegasporeEcology Evolution Behavior and Systematicsdescription
Megaspore ornamentation is one of the few morphological characters used in the taxonomy of the genus Isoëtes. In the present work, we test the application of this character for distinguishing some Isoëtes species occurring in the Mediterranean: Isoëtes sicula, which according to some authors should be included as a variety in I. histrix, and the recently described I. todaroana, whose affinity with other taxa is currently unknown. Two additional species (I. duriei, I. velata) were also included in the analysis. The megaspores were studied using scanning electron microscopy combined with energy-dispersive X-ray spectroscopy and chemical treatment. In all species, the megaspore surface is covered by a siliceous coating; removal of this coating reveals an underlying three-dimensional network of fused rodlets. A unique pattern of this network occurs in I. sicula, supporting its separation from I. histrix. Comparison between the patterns observed in the examined Mediterranean species shows that I. todaroana is most similar to I. histrix.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2012-03-01 |