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Status and Distribution of the Cave-Obligate Land Snails in the Appalachians and Interior Low Plateau of the Eastern United States

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Cave-obligate (troglobiotic) land snails are among the most understudied taxa inhabiting cave systems because of their small size and cryptic nature. Other than locality records and general descriptions of species’ morphology, information regarding most cave snail taxa is minimal. Given the importance of land snails as indicator species and as important drivers of ecosystem processes, this lack of knowledge on cave-obligate taxa impedes conservation management of subterranean snails and subterranean ecosystems in general. As a first step, we compiled and georeferenced all available distributional records for troglobiotic snail species within two major karst regions in the United States: The Interior Low Plateau (ILP) and Appalachians. We identified 16 new localities among these species from caves in Alabama, Tennessee, and Georgia from 2012 to 2016, yielding 8 new occurrences of two species in the ILP and 8 new occurrences of three species in the Appalachians. In total, we report 143 occurrences for five species in 124 caves, representing the most comprehensive dataset on the distribution of cave-obligate snails in the eastern United States to date. We also provide the first IUCN Red List conservation assessments for all five troglobiotic taxa and reexamine NatureServe conservation ranks. Our assessments indicate that three of the five species are considered at an elevated risk of extinction. Given these ranks and the threats identified to each species, we offer recommendations concerning the conservation and management of these cave snails and outline future areas of research for these taxa.
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... Regardless, these studies suggest that it is likely that C. stygium has recently colonized caves. Glyphyalinia specus is a wide-ranging snail known from 27 occurrences in five states [72]. Significant publications include Call [28], Hubricht [49,50,52,53], Barr [10], Poulson et al. [73], Dourson [74], Poulson [62], and Gladstone et al. [72]. ...
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Caves and other subterranean habitats with their often strange (even bizarre) inhabitants have long been objects of fascination, curiosity, and debate. The question of how such organisms have evolved, and the relative roles of natural selection and genetic drift, has engaged subterranean biologists for decades. Indeed, these studies continue to inform the general theory of adaptation and evolution. Subterranean ecosystems generally exhibit little or no primary productivity and, as extreme ecosystems, provide general insights into ecosystem function. The Biology of Caves and other Subterranean Habitats offers a concise but comprehensive introduction to cave ecology and evolution. Whilst there is an emphasis on biological processes occurring in these unique environments, conservation and management aspects are also considered. The monograph includes a global range of examples from more than 25 countries, and case studies from both caves and non-cave subterranean habitats; it also provides a clear explanation of specialized terms used by speleologists. This accessible text will appeal to researchers new to the field and to the many professional ecologists and conservation practitioners requiring a concise but authoritative overview. Its engaging style will also make it suitable for undergraduate and graduate students taking courses in cave and subterranean biology. Its more than 650 references, 150 of which are new since the first edition, provide many entry points to the research literature.
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