Spore morphology of Schizaea species (Schizaeaceae) from America

The Schizaeaceae family consists of only two genera, Actinostachys Wall and Schizaea Sm. These genera are mainly found in the tropical regions of the Old and New World with a few of them growing in temperate areas. The spores of the following Schizaea species from America were studied: Schizaea elegans (Vahl) Sw., S. fistulosa Labill., S. fluminensis Miers ex J.W. Sturm, S. incurvata Schkuhr, S. poeppigiana J.W. Sturm, S. pusilla Pursh, S. sprucei Hook. and S. stricta Lellinger. The study was performed with light microscope (LM) and scanning electron microscope (SEM). The spores are monolete of 33.6–99.4 μm in equatorial diameter and 21–65.8 μm in polar diameter. The ornamentation of the spores is verrucate, verrucate-tuberculate, rugate or reticulate. The most abundant morphology is the verrucate ornamentation. The exospore and the perispore form the ornamentation of the spores. In most of the species analyzed abundant spheroids, variable in size were observed irregularly distributed on the spore surface, even on the laesura. This study describes and illustrates the spores of some species for the first time. The results are discussed with a recent phylogeny of the genus.