Registered users receive a variety of benefits including the ability to customize email alerts, create favorite journals list, and save searches.
Please note that a BioOne web account does not automatically grant access to full-text content. An institutional or society member subscription is required to view non-Open Access content.
Contact firstname.lastname@example.org with any questions.
The phylogenetic position of Cystodium J. Sm. is studied here for the first time using DNA sequence data. Based on a broad sampling of leptosporangiate ferns and two plastid genes (rbcL and atpB), we show that Cystodium does not belong to the tree fern family Dicksoniaceae, as previously thought. Our results strongly support including Cystodium within the large polypod clade, and suggest its close relationship to the species-poor grade taxa at the base of the polypod topology (Sphenomeris and Lonchitis, or Saccoloma in this study). Further studies, with an expanded taxon sampling within polypods, are needed to fully understand the more precise phylogenetic relationships of Cystodium.
The gametophytes of four tropical, terrestrial species of Huperzia – H. crassa, H. cumingii, H. hypogaea, and H. saururus – grow in axenic culture on a nutrient medium containing inorganic nutrients and glucose. The gametophytes of all species are dorsiventral, axial structures, which can be straight, curved, narrow, or wide. Paraphyses and gametangia form on the dorsal surface and rhizoids on the ventral surface. The apical meristem is overarched by immature dorsal tissue. Minor differences in the paraphyses and gametangia exist among the species. These gametophytes are Type III gametophytes as is the case for the previously described gametophytes of two other terrestrial species of Huperzia.
This article is only available to subscribers. It is not available for individual sale.
Access to the requested content is limited to institutions that have
purchased or subscribe to this BioOne eBook Collection. You are receiving
this notice because your organization may not have this eBook access.*
*Shibboleth/Open Athens users-please
to access your institution's subscriptions.
Additional information about institution subscriptions can be foundhere