I first observed Scleria lithosperma a few months ago, on May 31, 2012, in Key Largo, Florida. This is the only Scleria species listed as Endangered in Florida. Including S. lithosperma, I’ve now observed nine of the ten Scleria species known from Florida. Scleria is a genus belonging to the monocotyledonous family Cyperaceae. All Scleria species of Florida are native here, except for Scleria lacustris.
The fruit of all Scleria species is an achene (as is true for all other species of Cyperaceae). An achene is a dry, indehiscent, one-seeded, fruit. Species of Scleria, like species of other cyperaceous genera, are distinguished from one another largely according to features of their achenes. All ten of our Scleria species have white achenes (an atypical feature among Florida Cyperaceae, overall) and their achenes are minute - ranging, collectively, from one to four mm long. Because the achenes are so small, the beginner requires a microscope to see them clearly and to identify Scleria plants to species.
Florida species of Scleria appear, superficially, grass-like and weedy, and the average person would consider them unremarkable. Yet, their achenes appear unique and beautiful under the microscope. I’ll now review selected features of the achenes. While doing so, I’ll refer to the handout which I’ve distributed today. 1