ABSTRACT Amphidium Schimp. is characterized by cushion-forming erect primary stems, linear-lanceolate leaves, and gymnostome capsules. The phylogenetic position of Amphidium is uncertain, with the genus having been variously included in Zygodontaceae Schimp., Rhabdoweisiaceae Limpr., Orthotrichaceae Arn. and Amphidiaceae M. Stech. A palynological investigation was performed of the three species of the genus that occur in the Americas: Amphidium lapponicum (Hedw.) Schimp., Amphidium mougeotii (Bruch & Schimp.) Schimp., and Amphidium tortuosum (Hornsch.) Cufod. Spores were observed and measured for greatest diameter under light microscopy both before and after acetolysis. Non-acetolyzed spores were observed under scanning electron microscopy to assess... |