This paper serves as an introduction to a multi-part monograph on the systematics of the subterranean amphipod genus Stygobromus, originally initiated by the late Dr. John R. Holsinger. The manuscript, left incomplete at the time of his death in 2018, was substantially completed and prepared for publication by the author, Julian J. Lewis, as a tribute to Holsinger’s lifelong contributions to subterranean biology. This first installment focuses on Stygobromus species from the Ozark, Arbuckle, and Ouachita mountains, extending into the glaciated plains of the central United States. The paper outlines the historical context of the work, the methodological challenges in preparing a decades-old manuscript for modern publication, and the taxonomic scope of the species treated. Special attention is given to preserving Holsinger’s original taxonomic intent and style, while acknowledging the limitations of pre-genetic systematics and the potential for cryptic species. This work represents a significant step toward completing Holsinger’s vision of a comprehensive treatment of Stygobromus systematics across North America.
An inventory of the paleontological resources in Virginia caves was initiated by the authors in 1996. Invertebrate and vertebrate fossil occurrences in Virginia were examined to understand the range and scope of fossils present in caves to aid in determination as to what should constitute cave significance in the documentation of paleontological resources for Virginia’s Significant Cave List. This cave study reviewed previously known vertebrate fossil sites and new vertebrate and invertebrate fossil sites before focusing on vertebrate fossil occurrences and the evidence of how they came to be deposited. As part of the inventory, to address the question of the percentage of Virginia caves that are paleontologically significant, 229 Virginia caves were examined to identify 100 caves with exposed non-human bones and/or teeth. Thirteen of the 100 caves yielded extinct or significant extirpated taxa, including one determined to have been excavated by E.D. Cope in 1867. Thirteen percent of the 100 bone caves examined or 5.7 % of the 229 study caves were documented as paleontologically significant. A selection of vertebrate cave fossils were radiocarbon dated and ranged in age from 11,986 +/- 76 to 39,300 +/- 1100 YBP. Uranium-thorium dating at one site suggests the fossil were older than 300,000 years and may be older than 450,000 YBP, indicating the age of this bone deposit is Pleistocene (Irvingtonian). A total of 43 cave sites were documented as paleontologically significant in the inventory and reported in Appendix C. PRIOVAC was recognized as an NSS Project from 2001 through 2006 and progress talks were presented at NSS Conventions in 1995, 1997, 1998, 2000, 2001, 2002, 2006, 2007, and a version of this summary in 2023 with abstracts published in the NSS Journal of Cave and Karst Studies and talks at the UIS Congresses in 1997 (Switzerland), 2001 (Brazil), and 2009 (US) published as papers in the UIS Proceedings. This paper is a summary report on PRIOVAC and the first publication of some of the bone dates and the U-Th dates.
Fossils accumulate in caves in multiple ways. Each introduces biases that must be understood before interpreting the assemblage. The ontogenetic age distributions of individual specimens of field mice, Peromyscus spp., based on tooth wear, provides insight into taphonomic pathways for two different talus deposits in Parker’s Pit, Black Hills, South Dakota. Main Cone accumulated under the modern 12 m vertical pit entrance throughout the Pleistocene and Holocene. The sink hole prohibits escape of randomly selected taxa. Red Cone formed as a talus slope in an old, now closed, entrance with a ramp-like slope that allowed animals to enter and exit the cave. Differences in ontogenetic age distributions between these two populations are statistically significant. Main Cone individuals show a wider and generally older age distribution than those from Red Cone. The older age distribution results from individuals surviving the vertical fall and living into old age in an essentially predator-free environment. These individuals probably subsisted on organic debris washed into the cave and resident invertebrates as observed in a living population of Peromyscus pectorralis in Longhorn Cavern, central Texas. The Red Cone population is ontogenetically younger, as exhibited by less dental wear, than the Main Cone population but slightly older than living populations studied in Washington, USA, and British Columbia, Canada. Bone damage indicative of predation by small carnivores, especially weasels (e.g., Mustela frenata) in the Red Cone sample is not apparent in the Main Cone population, reinforcing different taphonomic pathways of the two populations. The Red Cone sample is biased by predator selection. The Main Cone fossil assemblage likely represents a random, local sample of the biota around the cave that facilitates paleoecological analyses. The predator biased Red Cone sample is not amenable to reconstruction of communities but does provide insights into predator-prey interactions and selected species in the vicinity of the cave.
Stanton’s Cave is a large solutional cavern in the eastern region of Grand Canyon National Park, Arizona. The cave is best known to Quaternary paleontologists for its abundant Late Pleistocene and early Holocene fossil remains of mammals, birds, and Archaic artifacts. Re-examination of the fossil vertebrate collection, housed at the Grand Canyon Museum Collections, has resulted in re-identification of two fox dentaries (GRCA 76272) that were originally published as Urocyon cinereoargenteus (gray fox). Morphometric and morphological comparisons presented here find the dentaries diagnostic to Vulpes vulpes (red fox) and not the gray fox. The remains are the first record of Vulpes vulpes from the Grand Canyon and may be the first fossil evidence of the species from Arizona.
