Another Record of the Rare and Endangered SpeciesPhaeophyscia leana

Abstract

A collection of Phaeophyscia leana is reported from Hart County, Kentucky. Phaeophyscia leana (Tuck.) Essl. is a rare macrolichen that is endemic to the Ohio River Valley of eastern North America (Gillespie & Methven 2002). The species was originally discovered by Thomas G. Lea in the vicinity of Cincinnati, Ohio between 1834 and 1844. An absence of subsequent collections following the original discovery by Lea led Thomson (1963) to conclude that the species had gone extinct following the destruction of the type locality during the urbanization of the city of Cincinnati. It was thus with some jubilation that Skorepa (1984) reported the rediscovery of P. leana. Recently several individuals have conducted extensive field studies of Phaeophyscia leana to determine the status of extant populations and better elucidate the ecological niche the species occupies (Wilhelm & Master 1994, Wilhelm et al. 2000, Gillespie & Methven 2002). These extensive field studies led to the recognition of a total of eleven populations of P. leana restricted to periodically flooded bottomland forests along the Ohio and Wabash Rivers. During the meeting of the 2006 Tuckerman Workshop in southern Ohio I was fortunate to have the opportunity to observe Phaeophyscia leana. It is a very distinctive Phaeophyscia species with long, narrow, strap-like lobes and a pale undersurface. The combination of these characters, coupled with the overall size of the thallus makes it instantly recognizable in the field and herbarium. It was thus with some surprise that while revising specimens collected by Clyde F. Reed in Kentucky prior to their integration into the herbarium of the New York Botanical Garden (NY) I found a specimen of P. leana. The discovery of this collection extends the known distribution of P. leana. Further field studies are needed to determine if the species is still present at the locality, and to what extent other populations may occur along the Green River. The Green River is a tributary to the Ohio River, and all other known populations (extinct and extant) of P. leana are from the Ohio River and its tributaries. Specimen Examined. – U.S.A.