We report here the first record of a living Potamolepidae (Cherokeesia n. gen.) from the Nearctic Region and from the northern hemisphere. The new species Cherokeesia armata from southern Appalachians diverges at generic and specific level from all the other known taxa of the family Potamolepidae in its unique combination of diagnostic traits: gemmular theca armed by gemmuloscleres ranging from small strongyle-like spicules to stout, large oxeas; absence of pneumatic layer; spiny oxeas as main skeleton megascleres; irregular, slender pauci-to uni-spicular skeletal network. The most similar species belong to the genera Potamophloios and Oncosclera. The circumtropical biogeographic pattern of extant Potamolepidae, previously considered of Gondwanian to Gondwanian-like origin, is enlarged to the Nearctic. The present Tennessee discovery confirms a wider range of the family. An updated species inventory of Nearctic Spongillina, a checklist of the family Potamolepidae at the global level together with a key to the genera of Potamolepidae are also provided.

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A survey of four selected streams in the Tennessee portion of the Great Smoky Mountains National Park was conducted to document the presence of freshwater sponges. Streams were surveyed by wading and observing rock and log substrates for sponges. Sponges were viewed with a 10X magnifier for gemmules. If gemmules were present a portion of the sponge containing gemmules was collected. Scanning electron microscopy of gemmules and spicules was used for taxonomic identification. Two species, Radiospongilla crateriformis and Trochospongilla horrida, were discovered. Both were found in the Abrams Creek embayment of Chilhowee Lake. These findings represent the first records of freshwater sponges within the Great Smoky Mountains National Park.

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Of the 9K known species of sponges, less than 300 are freshwater (FW) and fewer than 35 are known from North America. Last surveyed in 1943 in Tennessee [1], only 4 species of freshwater sponges were identified, all form the Reelfoot Lake region of northwestern Tennessee. Sponges contain skeletal elements called spicules. Spicules of freshwater sponges are siliceous. Three forms of spicules, megascleres, microscleres and gemmoscleres, are recognized. Spicule shapes and sizes are quite varied and their use for differentiating species is well established [2]. Asexual reproductive resting stages known as gemmules are produced in response to adverse environmental conditions. The protective surface layer of a gemmule is composed of gemmoscleres. Of the three spicule types gemmoscleres are the most importance taxonomically.