VOL. 60, NO. 4, PP. 235-255 BULLETIN OF THE FLORIDA MUSEUM OF NATURAL HISTORY November 28, 2023 UNIVERSITY OF FLORIDA GAINESVILLE The FLORIDA MUSEUM OF NATURAL HISTORY is Florida’s state museum of natural history, dedicated to understanding, preserving, and interpreting biological diversity and cultural heritage. The BULLETIN OF THE FLORIDA MUSEUM OF NATURAL HISTORY is an on-line, open-ac- cess, peer-reviewed journal that publishes results of original research in zoology, botany, paleontology, archaeology, and museum science. Multi-author issues of related papers have been published together, and inquiries about putting together such issues are welcomed. Address all inquiries to the Editor of the Bulletin. David Blackburn, Editor for this issue Bulletin Committee Michal Kowalewski Michelle J. LeFebvre Jacqueline Miller Roger W. Portell Jonathan I. Bloch, Ex officio Member ISSN: 2373-9991 Copyright © 2023 by the Florida Museum of Natural History, University of Florida. All rights reserved. Text, images and other media are for nonprofit, educational, and personal use of students, scholars, and the public. Any commercial use or republication by printed or electronic media is strictly prohibited without written permission of the museum. Publication Date: November 28, 2023 This and other issues of the Bulletin can be freely downloaded at: https://www.floridamuseum.ufl.edu/bulletin/publications/ Send communications about this publication to: Editor of the Bulletin; Florida Museum of Natural History; University of Florida; P.O. Box 117800; Gainesville, FL 32611-7800 USA FAX: 352-846-0287; Email: bulletin@flmnh.ufl.edu URL: https://www.floridamuseum.ufl.edu/bulletin/home/ Cover image: Hypothetical reconstruction of the extinct salamander Batrachosauroides and multiple views of a fossil trunk vertebra (UF 111741) from the Willacoochee Creek Fauna (inset). Illustration by J. R. Bourque. mailto:bulletin@flmnh.ufl.edu https://www.floridamuseum.ufl.edu/bulletin/home/ A LATE MIOCENE OCCURRENCE OF THE EXTINCT SALAMANDER BATRACHOSAUROIDES (CAUDATA, BATRACHOSAUROIDIDAE) AND OTHER NEW CAUDATE FOSSILS FROM FLORIDA AND GEORGIA, USA Jason R. Bourque1, Edward L. Stanley2, and Richard C. Hulbert Jr.1 ABSTRACT Two partial vertebrae of the rare, large-bodied, aquatic salamander Batrachosauroides are reported from the Upper Miocene Love Bone Bed (late Clarendonian, ~10–9 Ma) Alachua County, Florida. They represent the latest occurrence of Batrachosauroides by 2.8–5.8 million years from previous records and are the latest account of the family Batrachosauroididae in the eastern United States, being either younger than or approximately coeval with fossils of Peratosauroides problematica from the Clarendonian San Pablo Formation of central California. While most Neogene Batrachosauroides in North America are from the warm interval spanning the Late Oligocene Warming (LOW) to the Middle Miocene Climatic Optimum (MMCO), this is the first unequivocal account well after the conclusion of the MMCO suggesting Florida was a post-MMCO refugium during global cooling in the Late Miocene. Batrachosauroides vertebrae from the late Hemingfordian Suwannee Springs site (Florida) and the late Barstovian Gragg Mine (southwestern Georgia) are also described. Two other caudate taxa are present at the Love Bone Bed, Ambystoma and a mid-sized Siren that is the most common amphibian in the Love Bone Bed Local Fauna. The presence and rarity of Ambystoma further corroborates the existence of peripheral or seasonal lentic aquatic habitats adjacent to the main lotic body of the Love Bone Bed deposit. Other salamanders from the paleocoastal Gragg Mine Local Fauna include Notophthalmus and Amphiuma n. sp., aff. Amphiuma pholeter. The latter represents the oldest record of the A. pholeter lineage and documents its presence in the Gulf Coastal Plain since the Middle Miocene. The Gragg Mine represents a unique interval in the southeast at the conclusion of the MMCO. Key words: Caudata; Batrachosauroides; Amphiuma; Siren; Ambystoma; Notophthalmus; Middle Miocene Climatic Optimum TABLE OF CONTENTSTABLE OF CONTENTS IntroductionIntroduction ........................................................................................................... ...........................................................................................................236 236 Locality BackgroundsLocality Backgrounds ........................................................................................... ...........................................................................................236236 Materials and MethodsMaterials and Methods .......................................................................................... ..........................................................................................240240 Systematic PaleontologySystematic Paleontology ....................................................................................... .......................................................................................241241 Description and ComparisonsDescription and Comparisons ............................................................................... ...............................................................................244 244 DiscussionDiscussion ............................................................................................................. .............................................................................................................246246 AcknowledgmentsAcknowledgments ................................................................................................ ................................................................................................251251 Author ContributionsAuthor Contributions ............................................................................................ ............................................................................................252252 Literature CitedLiterature Cited ..................................................................................................... .....................................................................................................252252 1 Division of Vertebrate Paleontology, Florida Museum of Natural History, University of Florida, Gainesville, Florida 32611, USA, jbourque@flmnh.ufl.edu; rhulbert@flmnh.ufl.edu 2 Division of Digital Imaging, Florida Museum of Natural History, University of Florida, Gainesville, Florida 32611, USA, elstanley@flmnh.ufl.edu Manuscript received 07/27/2023; accepted 10/04/2023; accepted 10/04/2023; electronically published 11/28/2023. Bourque, J. R., E. L. Stanley, and R. C. Hulbert Jr. 2023. A Late Miocene occurrence of the extinct salamander Batrachosauroides (Caudata, Batrachosauroididae) and other new caudate fossils from Florida and Georgia, USA. Bulletin of the Florida Museum of Natural History 60(4):235–255. https://doi. org/10.58782/flmnh.tzqg4599 mailto:jbourque%40flmnh.ufl.edu?subject= mailto:rhulbert%40flmnh.ufl.edu%20?subject= mailto:elstanley%40flmnh.ufl.edu?subject= 236 BULLETIN FLORIDA MUSEUM NATURAL HISTORY VOL. 60(4) INTRODUCTION The family Batrachosauroididae Auffenberg, 1958, is an enigmatic group of large-bodied aquatic sala- manders of uncertain phylogenetic affinities and one of the few major clades within Caudata to have gone extinct (Milner, 2000). Batrachosauroidids have been likened to extant Amphiuma and Siren with regard to morphotype, life history, and habitat preference (Holman, 2006). The previously report- ed fossil record of batrachosauroidids extends from the Cretaceous of Europe, Asia, and North America to the Late Miocene of North America (Auffenberg, 1961; Estes, 1963, 1969; Naylor, 1981; Sullivan, 1991; Denton and O’Neill, 1998; Holman, 2006; Gardner, 2022). Batrachosauroidids are thought to have dispersed from the western interior of the United States to the Gulf Coastal Plain by the Early Miocene (Taylor and Hesse, 1943; Albright, 1994; Bonett et al., 2013). The oldest species within the genus Batrachosauroides Taylor and Hesse, 1943 is Batrachosauroides gotoi Estes, 1969 from the lower Eocene (Wasatchian) Golden Valley Forma- tion of South Dakota (Estes, 1988). Neogene oc- currences of Batrachosauroides include reports from the lowermost Miocene (Arikareean) Toledo Bend locality in eastern Texas (Albright, 1994), and Early Miocene (Hemingfordian 1) Garvin Gully Fauna (includes Hidalgo Bluff locality) of eastern Texas (Auffenberg, 1958; Albright, 1994), Pollack Farm site in Delaware (Weems and George, 2013), and Thomas Farm locality in north central Florida (Estes, 1963). Middle Miocene or early Barstovian (Ba1) occurrences are from the Burkeville Fauna of southeastern Texas, which includes the Moscow site (aka. TMM 31057 and includes ‘Site 1’ of Polk County, Texas, and Barringer Farm) (Auffenberg, 1958; Holman, 1977) and Point Blank site (aka. TMM 31190; Hinderstein and Boyce, 1977), and Milwhite Gunn Farm Mine (Willacoochee Creek Fauna, Torreya Formation) of the northeastern panhandle of Florida (Bryant, 1991). The previous latest reported occurrences of Batrachosauroides dissimulans Taylor and Hesse, 1943 are from the late Barstovian (Ba2) Cold Spring Fauna of Texas (Auffenberg, 1958) (which includes the Fleming Formation of San Jacinto County, the type local- ity of B. dissimulans), Fort Polk Fauna of western Louisiana (Williams, 2009a, 2009b), and Gragg Mine assemblage in southwestern Georgia (Wil- liams, 2009b; Mörs and Hulbert, 2010). The Gragg Mine specimens are described and figured for the first time in the current article. The latest occurring previously reported member of the family is Pera- tosauroides problematica Naylor in Estes, 1981, from the Upper Miocene (Clarendonian) San Pab- lo Formation of central California (Naylor, 1981; Martín et al., 2012). Here, we present new fossil records of batra- chosauroidid salamanders and accompanying cau- date faunas from the southeastern United States, including a late occurrence of Batrachosauroides from the Upper Miocene (late Clarendonian, 10–9 Ma) Love Bone Bed, Alachua County, Florida. Pre- viously reported fossils of Batrachosauroides from the Early and Middle Miocene of Florida, Georgia, and Texas are also discussed and figured for com- parison. Digital models are provided for specimens currently housed in the Division of Vertebrate Pa- leontology, Florida Museum of Natural History (FLMNH), that have been figured previously as 2-dimensional illustrations or not at all in the lit- erature (see Auffenberg, 1958; Estes, 1963, 1969; Bryant, 1991; Williams, 2009b; Mörs and Hulbert, 2010). Anatomical terminology used in vertebral descriptions follows Gardner (2003). LOCALITY BACKGROUNDS We examined Batrachosauroides vertebrae from the following four localities in northern Florida and one locality in southernmost Georgia, USA. Love Bone Bed The Love Bone Bed is a highly fossiliferous late Clarendonian (10–9 Ma) fluvial deposit in Ala- chua County, Florida (Fig. 1; Webb et al., 1981; MacFadden and Hulbert, 1990). The diverse ver- tebrate fauna of about 100 species includes fish (dominated by gar), frogs, snakes, freshwater tur- tles, land tortoises, alligators, birds, and mammals (Jackson, 1978; Webb et al., 1981; Bourque, 2013, BOURQUE ET AL.: Late Miocene Batrachosauroides from Florida 237 Figure 1. Map of Florida, USA. Black dots indicate Miocene records of Batrachosauroides from the following localities: 1, Love Bone Bed, Alachua Co., FL, late Clarendonian, ~10– 9 Ma.; 2, Thomas Farm, Gilchrist Co., FL, early Heming- fordian, ~18.5–17.5 Ma.; 3, Suwannee Springs, Hamilton Co., FL, late Hemingfordian, ~17–16 Ma.; 4, Milwhite Gunn Farm Mine, Gadsen Co., FL, early Barstovian, ~16–15 Ma.; 5, Gragg Mine, Decatur Co., GA, late Barstovian, ~14.8–14 Ma. 2015; Valdes et al., 2017) and indicates an array of paleoenvironments associated with a subtropi- cal riverine community, such as estuarine, lentic, and flood plain habitats (Webb et al., 1981). Using the relative abundances of individuals belonging to large mammalian herbivore species reported by MacFadden and Hulbert (1990), only about 16% had low-crowned teeth suggesting a browsing diet (e.g., Tapirus and Aepycamelus, an extinct camelid with a giraffe-like ecology) in more closed habi- tats. This suggests that the surrounding landscape was predominantly open, relatively dry habitat covered with forbs, grasses, and scattered trees that supported herds of three-toed horses, rhinoceroses, lamine camelids, and gomphothere proboscideans. Webb et al. (1981: p. 537) concluded that whereas the main body of the Love deposit represented a high-energy stream channel, among aquatic spe- cies, lentic taxa far outnumbered lotic taxa in abun- dance. However, many of the fish and turtle groups they used to support this hypothesis are common in large, albeit slower moving portions of rivers today. Bourque (2015) noted the relative rarity of turtle taxa such as Kinosternon notolophus and a chelydrid that would have inhabited low energy wetlands (e.g., floodplain swamps) adjacent to the Love Bone Bed fluvial system contrasted to the abundance of more fluvial or generalist emydine and trionychid turtles. GraGG Mine Gragg Mine was a fuller’s earth clay mine located about 5.6 km southeast of Attapulgus in Decatur County, Georgia (ca. 30.72° N, 84.44° W; Fig. 1). The former mine’s location is now fully reclaimed, forested land. In 2004, D. P. Mihalik, who worked for the mining company Engelhard Corporation, informed the FLMNH that he had collected Miocene terrestrial vertebrate fossils on spoil piles in Gragg Mine, including a nearly com- plete molar of a gomphothere. By this time min- ing of sediments had stopped and reclamation had begun, thus there was no access to in situ depos- its. Mihalik twice led FLMNH field crews in 2004 and 2005 to the Gragg Mine and directed them to the general area where he had found terrestrial fossils. The spoil piles had by then been leveled by heavy equipment and vegetation covered most of the surface. However, several small, exposed areas of brown to tan, sandy clayey sediments were located, which Mihalik confirmed was the fossil-bearing deposit. While surface prospecting did not recover any fossils other than a few small shark and ray teeth, small dark ‘specks’ in the sediment suggested the presence of microfossils. Bryant (1991) had reported microfossils of am- phibians, reptiles, and mammals collected in simi- lar clay mines just 10 km southwest in Gadsden County, Florida. About two metric tons of sedi- ment (dried weight) was collected at Gragg Mine in 2004–2005 and transported to the FLMNH for screenwashing. Gragg Mine is assigned FLMNH VP locality number US018. The only previous mentions of fossils from Gragg Mine were in an 238 BULLETIN FLORIDA MUSEUM NATURAL HISTORY VOL. 60(4) unpublished dissertation (Williams, 2009b) and two sentences in Mörs and Hulbert (2010). This is the first description of the site, collecting meth- ods, overview of the entire fauna, and rationale for its geologic age. All known macrofossils from Gragg Mine were collected by D. P. Mihalik or his children. Most consist of isolated teeth. He donated a por- tion of his fossils from Gragg Mine to the FLMNH in 2005 and allowed the others to be molded and casted. The gomphothere molar (UF 216932) is of moderate size, low-crowned, and has a simple, sin- gle-trefoiled enamel pattern; it most likely repre- sents the genus Gomphotherium. The first appear- ance datum of Gomphotherium in North America is about 14.8 Ma and defines the beginning of the late Barstovian (Tedford et al., 2004; MacFadden et al., 2015). Two species of the hypsodont equid genus Calippus, C. proplacidus (UF 217573, UF 217583–217584) and C. circulus (UF 217582, UF 333980–333981), are present. These are decid- edly more advanced than the merychippine-grade equids found in the early Barstovian Willacoochee Creek Fauna of Bryant (1991) and are otherwise only known from late Barstovian faunas in Colora- do, Nebraska, Texas, and Florida (Hulbert, 1988). An upper premolar belongs to the large beaver Am- blycastor (UF 217575, Mörs and Hulbert, 2010), whose last occurrence is from the late Barstovian. Other fossils of large mammals from Gragg Mine belong to taxa that lived during the late Barstovian, but their chronologic ranges extend into older and younger land mammal ages. They include a medial phalanx from a medium-sized felid (UF 217576), a lower premolar of the rhinocerotid Teleoceras (UF 217581), and fossils representing three artiodactyl families, Tayassuidae (UF 217577, UF 554595), Camelidae (UF 333982, UF 554602), and Drom- omerycidae (UF 217585). The screenwashed sediment from Gragg Mine produced over 500 fossils of small mammals, mostly isolated teeth with very few partial jaws with one or two teeth. A preliminary estimate of the herpetofauna is 200–300 specimens, but this will likely increase as specimens continue to be cata- logued. This is significant as there are no other late Barstovian sites in the southeastern USA with large samples of small vertebrates. Other than the Cau- data described here, these specimens have yet to be studied in detail, so their identifications should be regarded as provisional. Fish and snakes are the most abundant non-mammalian constituents, but frogs, salamanders, chelonians, lizards, a croco- dilian, and birds are also present. The crocodilian is a small to mid-sized Alligator sp. (UF 554927– 554928). Chelonians are represented by scant shell fragments and isolated bones of the following: Tri- onychidae (UF 554920, UF 554925), Kinosterni- dae (UF 546658, UF 554910, UF 554926), Emydi- dae (Deirochelyinae) (UF 554922–554924), and Testudinidae (UF 554911–554919). Not surprisingly, rodents are the most com- mon and diverse group of small mammals, making up about 94% of the sample. At least five families are represented, with a possible sixth. There are two taxa of squirrels, both of small size. The more common is the chipmunk-like Nototamias sp. (16 teeth, UF 546996–546998, UF 547033–547045), whereas UF 547032, a lower third molar, is from a gliding squirrel (either Blackia or Sciurion) pre- viously not known from eastern North America (Godwin, 2008). The extinct family Mylagaulidae is known by a deciduous premolar (UF 546995) and a partial cheek tooth (UF 554690), neither of which is sufficient for generic identification. The extinct geomorph family Jimomyidae is well rep- resented by two genera, Jimomys (29 teeth; UF 546931–546939, UF 547046–547063) and Texo- mys (18 teeth; UF 546940–546948, UF 547064– 547072). Teeth of the former are relatively higher crowned than named species, and may represent a new species. The majority of the rodent speci- mens belong to either the Cricetidae (about 27% of all identifiable rodent teeth) or Heteromyidae (about 58%). The former is composed of one or more species of Copemys (UF 546913–546930, UF 547073–547139), while the latter likely con- tains multiple genera (UF 546949–546994, UF 547001–547002) based on variation among the premolars in the sample. All the heteromyid teeth are from small species with brachylophodont to mesodont dentitions. The potential sixth rodent BOURQUE ET AL.: Late Miocene Batrachosauroides from Florida 239 family in the screenwashed sample is represented by two cheektooth fragments that may belong to a small beaver (Castoridae) such as Monosaulax (UF 333978–333979). The non-rodents among the small mammals from Gragg Mine are a pos- sible didelphid marsupial (UF 546903), the hedge- hog Lantanotherium (UF 546905–546909, UF 547004–547006), two or more shrews (Soricidae; UF 546910–546912, UF 547009), the rabbit Hypo- lagus (UF 554718), and a bat. The latter is known from only a single specimen (UF 547008). It is the most complete dentary in the entire sample and preserves the alveoli for the entire tooth row but retains only the fourth premolar. Spelling of the ge- nus name Lantanotherium (as opposed to Lantha- notherium) follows McKenna and Bell (1997: p. 277), Gunnell et al. (2008), Furió and Alba (2011), and Crespo et al. (2020). The make-up of the Gragg Mine small mam- mal assemblage supports a Middle Miocene, Bar- stovian age. This is constrained by the first North American occurrence of Lantanotherium in the early Barstovian (Gunnell et al., 2008; Korth and Evander, 2016) and the joint last occurrence of Ji- momys and Texomys in the late Barstovian (Flynn et al., 2008). The latest published Miocene records for didelphid marsupials are early Barstovian from coastal Texas and Florida (Slaughter, 1978; Morgan and Pratt, 1988; Hayes, 2005). If the Gragg Mine Local Fauna is late Barstovian and the identifica- tion of UF 546903 as a didelphid is confirmed, then it would be the latest North American record for the family prior to the Great American Biotic Inter- change. Identification of the Gragg Mine soricids, leporid, heteromyids, and cricetids to the species level and comparisons with those from Barstovian faunas from Florida, Louisiana, Texas, Nebraska, and California are needed for a finer resolution of the chronology of the Gragg Mine Local Fauna. We suggest the early portion of the late Barstovian, ca. 14.8–14.0 Ma, best fits the current data, with primary correlations to the Cold Spring Fauna of Texas, Fort Polk Fauna of western Louisiana, the Keota Fauna of Colorado, and that portion of the Barstow Fauna of southern California collected be- low the Hemicyon Tuff (Tedford et al., 2004). The paleoenvironment is similar to that hy- pothesized for the nearby Willacoochee Creek Fau- na (Bryant, 1991), and likely represents a coastal, nearshore, deltaic, fluvial deposit with an admix- ture of marine, freshwater, and terrestrial verte- brates. Fossil deposits in this region of the south- eastern United States reflect a transient coastline in the Middle Miocene, farther north than today (Bry- ant et al., 1992). At 14.8–14.0 Ma, the Gragg Mine deposit is significant in that it represents a coastal plain environment in the southeastern United States at the conclusion and one of the warmest parts of the MMCO, when sea level was close to its highest in the Neogene (Zachos et al., 2001). At this time, Florida was almost entirely submerged with the possible exception of some small islands along the Brooksville Ridge of central Florida and a complex of islands and peninsulas along the border with Georgia and Alabama (Randazzo and Jones, 1997). MiLwhite Gunn FarM Mine (wiLLacoochee creek Fauna) This locality is one within a complex of mines in Gadsen County, Florida, that comprise the early Barstovian, Middle Miocene, Willacoochee Creek Fauna (Bryant, 1991). The Willacoochee Creek Fauna preserves a diverse array of terres- trial, freshwater, and marine taxa indicative of a coastal deltaic setting. Marine invertebrates were common in the sediments that preserved vertebrate fossils, and marine tetrapods include mysticete and odontocete cetaceans and dugongids (Bryant, 1991). The herpetofauna is diverse and includes a helodermatid lizard, and chelonians that represent the Kinosternidae, Podocnemididae (Pleurodira), small and large Testudinidae, Trionychidae, and Emydidae (Bryant, 1991; Bourque, 2013, 2016). However, a single Batrachosauroides vertebra (UF 111741) represents the only amphibian currently known from the fauna (Bryant, 1991). Suwannee SprinGS Little has been published about this road cut locality on US 129 just north of the Suwan- nee River in Hamilton County, Florida (Fig. 1; see Frailey, 1978; Tedford and Hunter, 1984; Bourque, 240 BULLETIN FLORIDA MUSEUM NATURAL HISTORY VOL. 60(4) 2013, 2016). It exposes the Lower Miocene Marks Head Formation (sensu Scott, 1988). Its age is ap- proximately 17–16 Ma (late Hemingfordian) based largely on the presence of the horse Merychippus gunteri (Bourque, 2013). The herpetofauna consists of a small alligatorid, Thecachampsa, two testudi- nids (a small and mid-sized species), podocnemi- did side-necked turtles (Pleurodira), and one of the oldest records of the mud turtle Kinosternon (Bourque, 2013; Bourque, 2016). Batrachosau- roides is represented by two partial vertebrae (de- scribed below). thoMaS FarM Thomas Farm is a paleosinkhole ephem- eral pond deposit in Gilchrist County, Florida. Vertebrate fossils are found in alternating beds of gray clay and calcareous sand or boulders (Simpson, 1932; Olsen, 1962; Pratt, 1990). Fos- sils of both large and small vertebrates are pres- ent in large numbers, with a total species richness in excess of 100. An early Hemingfordian age (He1) is indicated by the combined presence of the bear Phoberocyon, the mustelid Leptarctus, the rhinocerotids Menoceras and Floridaceras, and the canids Metatomarctus and Euoplocyon (Tedford et al., 2004). This differs from the age of Thomas Farm shown in the correlation chart in Tedford et al. (2004: fig. 6.2), that has it rang- ing over about one million years from the later third of the He1 through the first third of the He2. This duration is likely at least two orders of mag- nitude too long. As noted by Tedford et al. (2004: p. 213), there are major differences in He1 and He2 faunas, with 31 mammalian genera first ap- pearing in the He2. Of these, only one, the sci- urid Petauristodon, is known from Thomas Farm. However, the first appearance of Petauristodon is now known to have occurred earlier than the He2 (Whistler and Lander, 2003; MacFadden et al., 2014). Furthermore, fossils of the presump- tive He2 taxon Petauristodon occur in the same or lower beds at Thomas Farm as the He1 taxa Menoceras and Floridaceras (see Appendix 1). So, there is no longer reason to assign any portion of Thomas Farm to the He2. There is an exten- sive literature on fossils from Thomas Farm that was most recently summarized by Morgan and Czaplewski (2023). Despite the fact that thousands of fossils have been collected at Thomas Farm since its discovery in 1931, only a single specimen of Batrachosau- roides (an atlas vertebra, UF 7802) has been found, and that specimen was previously described by Es- tes (1963, 1969, 1981). The scarcity of Batracho- sauroides suggests that it was either uncommon at this ancient small pond or that the single atlas was potentially brought to the site from another wetland by a predator (e.g., raptor or other bird of prey) or scavenger before final deposition. MATERIALS AND METHODS High-resolution Computed Tomography (CT) scanning was performed on 20 vertebrae using the UF Nanoscale Research Facility’s Phoenix V|tome|X M dual tube CT system. Samples were suspended in cotton-filled polyethylene tubes and scanned as a sequential batch using the Datos|X A software (Waygate Technologies, Skaneateles, NY, USA). Scanning parameters were modified to max- imize resolution, contrast and signal to noise (see Appendix 2). Radiographs were converted to to- mograms using Datos|X R (Waygate Technologies, Skaneateles, NY, USA), using the edge enhance- ment, ROI filter, and inline median modules. The resulting datasets were segmented, visualized, and analyzed in VGStudioMax 2023.2 (Volume Graph- ics, Heidelberg Germany). Tomogram stacks and stereolithography mesh files are available to down- load from www.Morphosource.org (see Appendix 2 for DOI links). inStitutionaL aBBreviationS FLMNH, Florida Museum of Natural His- tory, University of Florida, Gainesville, Florida; TMM, Texas Vertebrate Paleontology Collection, Jackson School Museum of Earth History, Univer- sity of Texas at Austin, Austin, Texas; UF, Division of Vertebrate Paleontology, Florida Museum of Natural History, University of Florida, Gainesville, Florida; UF/H, Division of Herpetology, Florida https://www.floridamuseum.ufl.edu/florida-vertebrate-fossils/land-mammal-ages/hemingfordian/ BOURQUE ET AL.: Late Miocene Batrachosauroides from Florida 241 Museum of Natural History, University of Florida, Gainesville, Florida. UF/TRO, formerly part of the Timberlane Research Organization Collection, Lake Wales, Florida, now housed at the Division of Vertebrate Paleontology, Florida Museum of Natu- ral History, Gainesville, Florida. FoSSiL caudate SpeciMenS exaMined Batrachosauroides sp.: UF 293802, UF 546455 (Love Bone Bed, FL), UF/TRO 546528– 546529 (Suwannee Springs, FL), UF 2013 (Mos- cow locality, Burkeville Fauna, TX; see also Auffenberg, 1958: fig. 2), UF 7802 (Thomas Farm, FL; see also Estes, 1963: fig. 2 lower right), UF 111741 (Milwhite Gunn Farm Mine, FL; see also Bryant, 1991: fig. 5A–B), UF 217589, UF 546635, UF 546653–546656 (Gragg Mine, GA); Ambys- toma sp.: UF 546456–546458 (Love Bone Bed, FL); Siren sp.: UF 403843–403867, UF 546459– 546470, UF 546853 (Love Bone Bed, FL); Siren simpsoni: UF 2767 (Haile 6A); Pseudobranchus sp.: UF 2768 (Haile 6A); Amphiuma n. sp., aff. A. pholeter: UF 546636–546641, UF 546652 (Gragg Mine, GA); Notophthalmus sp.: UF 546642– 546651 (Gragg Mine, GA). Numerous extant sala- mander skeletons used for comparisons are housed in the Division of Herpetology, FLMNH. SYSTEMATIC PALEONTOLOGY Subclass LISSAMPHIBIA Haeckel, 1866 Order CAUDATA Scopoli, 1777 Family BATRACHOSAUROIDIDAE Auffen- berg, 1958 Genus BATRACHOSAUROIDES Taylor and Hesse, 1943 Type Species.—Batrachosauroides dissimu- lans, holotype TMM 10038-2234, skull and jaws only (Taylor and Hesse, 1943) from the late Barsto- vian Cold Spring Fauna of eastern Texas. The holo- type was reported missing for nearly four decades (Estes, 1969; Holman, 2006); however, has since been located and is currently housed at TMM under the revised catalog number TMM 10038-2234 (ex- TAM 2234) (J. C. Sagebiel, TMM, pers. comm.). Auffenberg (1958) attributed vertebrae collected from “the same bed as that of the type skull”, as well as vertebrae from similarly aged localities in the re- gion (now considered part of the early Barstovian Burkeville Fauna), to B. dissimulans and provided an amended diagnosis for the species (p. 172–173). Estes (1981: p. 30) subsequently provided a differ- ential diagnosis to distinguish B. dissimulans from the Eocene species Batrachosauroides gotoi. Figure 2. Trunk vertebrae of Batrachosauroides sp. from the late Clarendonian Love Bone Bed, Florida. A, UF 293802 and B, UF 546455 (subadult). Aspects from left to right: anterior, left lateral, posterior, right lateral, dorsal, and ventral. 242 BULLETIN FLORIDA MUSEUM NATURAL HISTORY VOL. 60(4) BATRACHOSAUROIDES sp. (Figs. 2–4) Locality and Age.—Love Bone Bed, Alach- ua County, Florida; Alachua Formation, late Clar- endonian (Cl3), Late Miocene, 10–9 Ma (Webb et al., 1981; Tedford et al., 2004). Referred Specimens.—UF 293802 and UF 546455, partial trunk vertebrae (Fig. 2). Locality and Age.—Gragg Mine, Decatur County, Georgia; Middle Miocene, Barstovian (Ba2), 14.8–14 Ma (refined age presented here; see also Mörs and Hulbert, 2010). Referred Specimens.—UF 217589, UF 546635, UF 546653–546656, partial trunk verte- brae (Fig. 3). Locality and Age.—Milwhite Gunn Farm Mine, Gadsen County, Florida; Torreya Formation, Middle Miocene, Barstovian (Ba1), ~16–15 Ma (Bryant, 1991). Referred Specimen.—UF 111741, trunk ver- tebra (Fig. 4E). Previously figured as line illustra- tion in Bryant (1991: fig. 5A–B). Locality and Age.—Suwannee Springs, Hamilton County, Florida; Marks Head Formation, Early Miocene, Hemingfordian (He2), ~17–16 Ma (Frailey, 1978; Tedford and Hunter, 1984; Bourque, 2013). Referred Specimens.—UF/TRO 546528– 546529 (Fig. 4B–C). Locality and Age.—Thomas Farm, Gilchrist County, Florida; Early Miocene, Hemingfordian (He1), ~18.5–17.5 Ma (Morgan and Czaplewski, 2023). Referred Specimen.—UF 7802 (Fig. 4A). Previously figured as a stippled illustration in Estes (1963: fig. 2 lower right). Remarks.—Batrachosauroides specimens from localities in the southeastern Gulf Coastal Plain (Florida and Georgia) are not identified to the species level here. These fossils consist of iso- lated and mostly incomplete vertebrae, whereas the holotype of Batrachosauroides dissimulans is a cranio-dental specimen (Taylor and Hesse, 1943). While Auffenberg (1958) attributed ver- tebrae from the Burkeville Fauna (Texas) to the Figure 3. Trunk vertebrae of Batrachosauroides sp. from the late Barstovian Gragg Mine, Georgia. A, UF 217589; B, UF 546635; and C, UF 546653. Aspects from left to right: anterior, left lateral, posterior, right lateral, dorsal, and ventral. BOURQUE ET AL.: Late Miocene Batrachosauroides from Florida 243 species B. dissimulans under the assumption that they were collected from the same deposit and general area, our current understanding is that those Burkeville vertebrae are at least one mil- lion years older than the type specimen from Cold Spring (Texas). Similarly, Bryant (1991) attribut- ed a nearly complete trunk vertebra (UF 111741) from the Milwhite Gunn Farm Mine to the spe- cies B. dissimulans, which is approximately one million or more years older than Cold Spring. Ad- ditionally, Estes (1963, 1969, 1981) attributed the only known Batrachosauroides specimen from Thomas Farm (an atlas, UF 7802) to the species B. dissimulans; however, that account is the oldest record from Florida and ~3.5 million years older than the type locality at Cold Spring. Furthermore, UF 7802 is notably larger than most trunk verte- brae from younger deposits in Florida. A single Batrachosauroides vertebra (UF 217589) previ- ously referred to the species B. dissimulans from Figure 4. Vertebrae of Batrachosauroides sp. A, UF 7802, atlas from Thomas Farm, Florida (see also Estes, 1963: fig. 2 lower right). B, UF/TRO 546528 and C, UF/TRO 546529 trunk vertebrae from Suwannee Springs, Florida. D, UF 2013 trunk verte- bra from the Moscow locality (Burkeville Fauna), Texas (see also Auffenberg, 1958: fig. 2). E, UF 111741 trunk vertebra from the Milwhite Gunn Farm Mine (Willacoochee Creek Fauna), Florida (see also Bryant, 1991: fig. 5A–B). Aspects from left to right: anterior, left lateral, posterior, right lateral, dorsal, and ventral. 244 BULLETIN FLORIDA MUSEUM NATURAL HISTORY VOL. 60(4) the Gragg Mine (Mörs and Hulbert, 2010) was not identified to the species level based on any specific characters according to RCH; however, the Gragg Mine specimens are essentially contemporane- ous with the type of B. dissimulans from the Cold Spring Fauna. Given the extensive time span that Batrachosauroides was present in the Gulf Coastal Plain (~23–9 Ma) and the absence of cranial fos- sils to compare to the holotype, it is possible that more than a single species was present in the re- gion during the Miocene. Therefore, we prefer to be taxonomically conservative and open to the possibility of undocumented diversity within Ba- trachosauroides. DESCRIPTION AND COMPARISONS Love Bone Bed SpeciMenS Two partial trunk vertebrae are known from the Love Bone Bed. UF 293802 is a partial opisthocoelous trunk vertebra of a large-bodied salamander (Fig. 2A). From what is preserved, it measures 12.14 mm in total length, 9.59 mm long along the centrum, 10.67 mm wide, and 11.82 mm tall. Its broken and polished preservation implies that it endured sedimentary abrasion and transport (commonly observed on many specimens from this site). The anterior condyle head, right margin of the posterior cotyle, posteriormost end of the neural spine, postzygapophyses, and transverse or rib-bearing processes are not preserved. Although the ossified condyle head is missing, the preserved condyle base is laterally compressed making it ovoid or taller than wide in anterior outline. The preserved basal most portion of the left transverse processes suggests those were bifurcate in life. Dorsally, there is a distinct neural crest that would have extended to the posteriorly elongate neural spine in life. The neural spine is broken along the plane of the postzygapophyses. The transverse surface of the neural spine break is relatively broad indicating that the neural spine would have extended well posterior to the ver- tebral centrum as is typical for the family. Like other Batrachosauroides vertebrae examined, it lacks basapophyses. The vertebrarterial canal ter- minates anteriorly just below the prezygapophy- ses and adjacent to the anterior condyle, and pos- teriorly below the postzygapophyses and adjacent to the posterior cotyle. The vertebrarterial canals are distinctly visible in anterior aspect in that they protrude laterally from the centrum. There is a prominent subcentral keel that extends the length of the centrum, from the anterior condyle to the posterior cotyle. This keel is constricted medially and broadest anteriorly and posteriorly. Approxi- mately midway along the base of the subcentral keel is a pair of subcentral foramina. The prezyg- apophyses are upwardly oriented at a ~45° angle. The upper margin of the neural canal is highly vaulted. UF 546455 is a partial opisthocoelous ver- tebral centrum of a subadult (Fig. 2B). Its identi- fication as a subadult is due to its small size and broad width of the notochordal canal. The centrum length is ~4.4 mm and it is 4.26 mm tall anterior- ly. The paired prezygapophyses are preserved and upwardly oriented at greater than a 45° angle. The neural canal is highly arched. A strong, straight subcentral keel is present with a subcentral fora- men preserved on the left side. The neural spine and postzygapophyses are not preserved. The left transverse processes are only basally preserved and were likely bifurcate in life. GraGG Mine SpeciMenS Six fragmentary trunk vertebral centra of Ba- trachosauroides are known from the Gragg Mine. UF 217589 (Fig. 3A) is a relatively complete opis- thocoelous centrum with the right prezygapophysis preserved. The neural spine and postzygapophy- ses are missing. It is the largest specimen from the Gragg Mine, 13.21 mm long at the centrum and 9.91 mm tall anteriorly. The anterior condyle is well ossified. The posterior cotyle is preserved but chipped along the bottom margin. The prezyg- apophyses are upwardly oriented approximately at a 45° angle. The neural canal is highly arched medially as with other Batrachosauroides trunk vertebrae. The transverse processes are missing but basally preserved on the right side and were likely bifurcate. A strong, straight subcentral keel BOURQUE ET AL.: Late Miocene Batrachosauroides from Florida 245 is present with paired subcentral foramina located on either side. UF 546635 (Fig. 3B) is a relatively complete centrum with complete condyle and cot- yle with a chipped outer margin. The centrum is 8.14 mm long. The subcentral keel and foramina are preserved but the former is chipped. UF 546653 (Fig. 3C) is the second-most complete specimen in preserving the anterior condyle and posterior coty- le and the centrum is 7.91 mm long. The condyle is well ossified with a pinhole sized notochordal ca- nal externally. The subcentral keel is straight with paired subcentral foramina positioned medially at the base of the keel. The paired vertebrarterial canals are preserved. UF 546654–546656 (not fig- ured) are isolated fragments of the anterior portions of centra with condyles preserved. MiLwhite Gunn FarM Mine SpeciMen A single opisthocoelous trunk vertebra (UF 111741) (Fig. 4E) is known from this mine local- ity and the entire Willacoochee Creek Fauna. It is one of the most complete trunk vertebrae of Ba- trachosauroides in southeastern North America in missing only the posteriormost tip of the neural spine and distal ends of the transverse processes. Measurements were previously provided by Bry- ant (1991) and are as follows: centrum length (CL), 11.1 mm; centrum width at narrowest por- tion of zygapophyseal ridges (CW), 6.3 mm; cen- trum height at anterior margin (CH), 4.6 mm; and neural arch height above centrum (NH), 8.2 mm. Our measurements differ only slightly and are as follows: CL, 10.93 mm; CW, 5.38; CH, 4.73 mm; NH, 7.6 mm. The prezygapophyses and postzyg- apophyses are inclined at approximately a 45° angle. The subcentral keel is relatively straight in lateral view, with paired subcentral foramina positioned medially at the base of the keel. The anterior condyle is well ossified, has a deep con- cavity at the center, and the notochordal canal is enclosed indicating the specimen is that of an adult. The neural spine is elongate and extends ~2.98 mm posterior to the centrum at the margin of the posterior cotyle; however, the neural spine would have been more extensive in life given the distal tip is missing on the fossil. A tall, thin me- dial crest is preserved that runs the length of the neural spine. Suwannee SprinGS SpeciMenS Two partial trunk vertebrae are known from Suwannee Springs. UF/TRO 546528 (Fig. 4B) is the partial anterior portion of a vertebra. The prezygapophyses are inclined at approximately a 45° angle from the centrum. The neural canal is highly vaulted medially between the prezygapoph- yses. The anterior condyle is well ossified and the notochordal canal is enclosed externally. The cen- trum is tall ventrally with a pronounced subcentral keel. The anterior terminus of the vertebrarterial canal is positioned well forward on the centrum and under the main portion of the prezygapophyses similar to the specimens from the Love Bone Bed. The anteriormost portion of the neural spine is pre- served between the prezygapophyses and is broad and thick. UF/TRO 546529 (Fig. 4C) is a partial ver- tebra that preserves most of the dorsal half. It is 11.97 mm long from the pre- to postzygapophy- ses. It was opisthocoelous in life, but the condyle is broken and missing. The prezygapophyses are inclined at approximately a 45° angle, and the neu- ral canal is highly vaulted medially between the prezygapophyses. The dorsal crest is mostly pre- served and is tall anteriorly, where it begins at the posterior portion of the prezygapophyses, and the postzygapophyses extend posteriorly well beyond the posterior cotyle margin of the centrum similar to UF 111741 (Fig. 4E). thoMaS FarM SpeciMen A single atlas vertebra (UF 7802) (Fig. 4A) represents the only record of Batrachosauroides from Thomas Farm, and the oldest record of a batrachosauroidid from Florida. The atlas is rela- tively large compared to other Batrachosauroides vertebrae from Florida. UF 7802 was previously described by Estes (1963, 1969, 1981). Measure- ments from Estes (1963) are as follows: intercoty- lar maximum width (MW), 14.3 mm; and maxi- mum centrum length (ML), 7.5 mm. Our measure- ments are nearly identical: MW, 14.2 mm; and ML, 246 BULLETIN FLORIDA MUSEUM NATURAL HISTORY VOL. 60(4) ~7.2–7.7 mm. As stated by Estes (1963), the atlas is robust and well ossified, and the posterior por- tion of the neural spine is missing but would have extended posteriorly well past the centrum. The postzygapophyses are oriented at slightly less than a 45° angle and extend posteriorly ~3.5 mm past the posteriormost margin of the posterior cotyle of the centrum. coMpariSonS In most aspects, UF 293802 and UF 546455 (Fig. 2) from the Late Miocene Love Bone Bed are very similar to Batrachosauroides trunk ver- tebrae from other localities examined for this study. However, the centrum of UF 293802 is more laterally compressed (dorso-ventrally elon- gate) and the subcentral keel ventrally taller than the Middle Miocene Batrachosauroides vertebra UF 217589 (Fig. 3A) from the Gragg Mine, UF 111741 (Fig. 4E) from the Milwhite Gunn Farm Mine, and UF 2013 (Fig. 4D) from the Moscow locality in Texas. It is unclear if this is a diagnos- tic character of a new species, or perhaps this fea- ture is variable throughout the vertebral column and signifies a particular region of the body. The prezygapophyses are more anteriorly extensive in UF 111741 than in UF 293802, but these seem eroded in the latter. Notably, the anterior terminus of the vertebrarterial canal is situated more anteri- orly in UF 293802, UF 546455, UF/TRO 546528, and UF/TRO 546529 than in UF 111741 and UF 217589, where the terminus is situated near the posterior base of the prezygapophyses in the lat- ter two specimens. The vertebrarterial canals are wide anteriorly and protrude laterally so they are distinctly visible in anterior view in UF 293802 and UF 217589, perhaps indicating these are from a similar body region. The Love Bone Bed specimens are approximately contemporaneous or younger than another batrachosauroidid, Pera- tosauroides problematica from central California (Naylor, 1981). However, P. problematica was described as having amphicoelous vertebrae in contrast to the Love Bone Bed vertebrae (and all specimens from the eastern United States) which differ in having opisthocoelous vertebrae. DISCUSSION Batrachosauroides and warM paLeocLiMate Batrachosauroidids are one of the few major caudate groups to have gone extinct (Milner, 2000), and their extinction is likely correlated with cli- matic shifts, specifically with global cooling in the Late Miocene. Previous accounts of batrachosau- roidids in North America are from intervals when globally warm mean annual temperatures (MATs) are hypothesized to have been much warmer than today (Zachos et al., 2001; Woodburne, 2004) (Fig. 5). Batrachosauroides was most common in the Southeastern Coastal Plain (Williams, 2009b; Bonett et al., 2013) from the interval that spans the Late Oligocene Warming (LOW) to the Middle Miocene Climatic Optimum (MMCO), a period of global climate change marked by megathermal temperatures at the onset (during LOW) and con- clusion (during MMCO) of this warming event (Zachos et al., 2001). It was thought that Batracho- sauroides did not survive long past the MMCO as summarized by Bonett et al. (2013: fig. 3). Records from the late Barstovian (Ba2) Fort Polk Formation of western Louisiana (Williams, 2009a, 2009b) and Gragg Mine of southwestern Georgia are from the conclusion of the MMCO and at the onset of global cooling (Zachos et al., 2001; Woodburne, 2004). The record from the Love Bone Bed is one of the latest reports of Batrachosauroididae and the lat- est of Batrachosauroides. This implies that in the southeastern United States, Florida was a likely post-MMCO refugium for these salamanders dur- ing the Late Miocene, which were previously more common and well-distributed across the Gulf and Atlantic coastal plains during the warmer Early and Middle Miocene (Taylor and Hesse, 1943; Auffen- berg, 1958; Estes, 1963, 1969; Holman, 1977; Hinderstein and Boyce, 1977; Bryant, 1991; Al- bright, 1994; Mörs and Hulbert, 2010). The record from the Love Bone Bed is also one of the most southern occurrences of the family, and the most southern occurrence of Batrachosauroides, albeit not by much. At the time of the Love Bone Bed deposition, global MATs would have been much cooler than those experienced from the LOW to the BOURQUE ET AL.: Late Miocene Batrachosauroides from Florida 247 MMCO, and similar to those last experienced in the late Oligocene, just prior to the LOW (Zachos et al., 2001). This is significant when considering there are no Batrachosauroides fossils known from the Oligocene and their last pre-Oligocene occur- rence was from the early Eocene (Wasatchian) of Figure 5. Correlation timeline comparing known localities and faunas with Batrachosauroides fossils in the Gulf and Atlantic coastal plains to global temperature shifts (Zachos et al., 2001; modified from Tedford et al., 2004). Previously published Ba- trachosauroides records from the following (bottom to top): Toledo Bend (Albright, 1994); Pollack Farm (Weems and George, 2013); Hidalgo Bluff (aka. TMM 40067; part of Garvin Gully Fauna) (Albright, 1994); Thomas Farm (Estes, 1963); Burkeville Fauna, which includes Moscow (aka. TMM 31057 and includes ‘Site 1’ of Polk County, TX, and Barringer Farm, TX) (Auffen- berg, 1958) and Point Blank site (aka. TMM 31190; Hinderstein and Boyce, 1977); Milwhite Gunn Farm Mine, Willacoochee Creek Fauna (Bryant, 1991); Gragg Mine (Mörs and Hulbert, 2010; age range amended here); Cold Spring Fauna (Auffenberg, 1958); Fort Polk Fauna (Williams, 2009a, 2009b). Asterisk (*) indicates type occurrence of Batrachosauroides dissimulans. Darkened portion of temperature gradient indicates warm interval bracketed by the Late Oligocene Warming (LOW) and the conclusion phase of the Middle Miocene Climatic Optimum (MMCO) and the onset of global cooling at approximately the Barstovian-Clarendonian NALMA boundary. All previous records of the species B. dissimulans or B. aff. dissimulans fall within this interval. 248 BULLETIN FLORIDA MUSEUM NATURAL HISTORY VOL. 60(4) North Dakota with Batrachosauroides gotoi (Es- tes, 1981; Holman, 2006; Williams, 2009b) during the Greenhouse World (Zachos et al., 2001). It is unclear if batrachosauroidids made it to warmer lower latitudes in continental North America, such as Mexico or Central America, by the Oligocene and then emigrated north to the Gulf and Atlantic coastal plains when MATs were more favorable from the LOW to the MMCO. In addition to Batra- chosauroides, an increasing number of Greenhouse World and xeric-associated reptiles and amphibi- ans made a relatively brief appearance in the south- eastern United States from the interval just prior to LOW through the MMCO, such as Xenochelys floridensis (Bourque, 2013), Kinosterninae gen. et sp. nov. (Bourque, 2015; fig. 10), podocnemidid pleurodire turtles (Bourque, 2016), dermatemydid turtles (Albright, 1994), helodermatid and xantu- siid lizards (Bryant, 1991; Hayes, 2000; Hulbert, 2001; Bhullar and Smith, 2008; Bourque, 2013), a rhinophrynid frog (Blackburn et al., 2019), and dwarf alligatorids (Bourque, 2013; Hastings et al., 2023). These accounts further support the south- eastern United States, in particular Florida, as a post-Eocene, late Oligocene to Middle Miocene refugium for exceptionally warm or tropically adapted reptiles and amphibians. Despite the fact that the account of Batrachosauroides from Love Bone Bed is well after the MMCO, the presence and commonality of co-occurring ectothermic, pre- sumably warm-adapted, vertebrates such as giant tortoises and two different crocodilian taxa sug- gests a warm climate with mild winters in north- central Florida. The rarity of batrachosauroidids from the Love Bone Bed is notable in that many thousands of macro- and microfossils comprising a multi- tude of different taxa were collected from the site during its excavation (Webb et al., 1981; over 45,000 cataloged specimens in the FLMNH Ver- tebrate Paleontology collection as of 6/11/2023). This suggests that Batrachosauroides was excep- tionally rare in the Late Miocene of Florida, and/ or that it preferred peripheral habitats adjacent to the main lotic deposit of the Love Bone Bed. The tumbled preservation of UF 293802 suggests that it was fluvially transported before final burial, perhaps having originated from a more still-water habitat, such as a floodplain swamp or an oxbow in the river. However, its color and preservation resemble that of other Love Bone Bed fossils, so it is unlikely that the specimen was reworked from a stratigraphically older deposit. Many Siren fossil vertebrae from the Love Bone Bed exhibit a similar preservation and despite there being hun- dreds of specimens, pristine representatives are rarer than worn and polished ones. Using extant Siren and Amphiuma as modern analogs like oth- er workers have proposed (Holman, 2006), it is probable that Batrachosauroides preferred slower moving portions of rivers and still, vegetated wet- lands. other caudateS FroM the Love Bone Bed Caudates from the Love Bone Bed are nu- merically dominated by vertebrae of a medium- sized Siren sp. (UF 403843–403867, UF 546459– 546470, and numerous uncatalogued specimens), first reported by Webb et al. (1981) (Fig. 6A–C). The Siren likely represents an extinct species but compares well in approximate size and general morphology to living Siren intermedia examined (UF/H 158868). None approaches the large body size of extant Siren lacertina. The largest verte- brae are approximately the same size as the ex- tinct Siren simpsoni from the Late Miocene (late Hemphillian) Haile 6A locality, Alachua County, Florida (Goin and Auffenberg, 1955). Although both have a relatively tall neural spine, S. simp- soni differs from the Love Siren in having a more laterally pronounced and very straight in- terzygapophyseal ridge when viewed in lateral aspect, whereas the interzygapophyseal ridge is less pronounced and curved down at the trans- verse process in the Love Siren. Two sirenids, Siren simpsoni and Pseudobranchus sp. (e.g., UF 2768), co-occur at Haile 6A. We compared some extremely small sirenid fossil vertebrae collected at the Love Bone Bed to the extant dwarf sirens, Pseudobranchus striatus and Pseudobranchus ax- anthus. These resemble P. striatus and P. axanthus in having a slightly concave (in lateral aspect) BOURQUE ET AL.: Late Miocene Batrachosauroides from Florida 249 subcentral keel (Goin and Auffenberg, 1955) and a very low dorsal crest (e.g., UF 546469–546470, and UF 546853); however, they more closely re- semble Siren intermedia in overall height to width proportions (vertebrae of Siren are taller whereas those of Pseudobranchus more compressed and therefore elongate in appearance), in having a more prominently ridged subcentral keel, in lack- ing a pronounced lateral constriction posterior to the transverse processes in dorsal-ventral aspect Figure 6. Caudate trunk vertebrae from the Love Bone Bed, Florida. A–C, Siren sp., represented by A, UF 546459; B, UF 546462; and C, UF 546464. D–F, Ambystoma sp., represented by D, UF 546456; E, UF 546457; and F, UF 546458. Aspects from left to right: anterior, left lateral, posterior, right lateral, dorsal, and ventral. 250 BULLETIN FLORIDA MUSEUM NATURAL HISTORY VOL. 60(4) (P. striatus has a constricted vertebral waist), and in having a well-developed continuous interzyg- apophyseal ridge (P. striatus lacks a defined ridge centrally on the vertebra). Given that the oldest described Pseudobranchus fossils are Pseudo- branchus vetustus from the Late Miocene (early Hemphillian 1) of north-central Florida (Goin and Auffenberg, 1955), it would not be unexpected to find older Miocene fossils with polymorphisms or a unique suite of shared features between the two living genera as seen in some specimens from the Love Bone Bed sample. Mole salamanders of the genus Ambystoma are extremely rare and previously unreported, rep- resented by only three vertebral specimens (UF 546456–546458; Fig. 6D–F). These trunk verte- brae compare well with those of extant Ambystoma maculatum and Ambystoma opacum examined in being amphicoelous, stoutly proportioned, having tiny anterior basapophyses or subtle basapophy- seal crests, a narrowly spaced notch at the bifurcate crest of the neural spine (vs. a more widely spaced notch in plethodontids), and a relatively broad centrum ventrally. The rarity of ambystomatids and batrachosauroidids at the Love Bone Bed fur- ther corroborates the presence of low energy wa- ter bodies adjacent to the main river body as sug- gested by Webb et al. (1981: p. 537) and Bourque (2015). The majority of living ambystomatids are terrestrial and require ephemeral or lentic to slug- gish fish-free water bodies for breeding (Petranka, 1998). Given that the Love Bone Bed was lotic and predatory fish were the most common fossils found there, the main stream body of the deposit would Figure 7. Caudate trunk vertebrae from the Gragg Mine, Georgia (B–D). A, UF/H 152951, Recent Amphiuma pholeter com- pared to B, UF 546636, Amphiuma n. sp., aff. A. pholeter. Notophthalmus sp., represented by C, UF 546644 and D, UF 546643. Aspects from left to right: anterior, left lateral, posterior, right lateral, dorsal, and ventral. BOURQUE ET AL.: Late Miocene Batrachosauroides from Florida 251 have been inhospitable for these salamanders. This suggests that the Ambystoma vertebrae were either transported from a nearby peripheral habitat or that an individual Ambystoma would on occasion enter the river system. other caudateS FroM the GraGG Mine Salamanders from the Gragg Mine include Batrachosauroides (described above), a small- bodied Amphiuma, and Notophthalmus, the latter of which is the most abundant caudate in the fauna. All are represented by isolated vertebrae. The trunk vertebrae of the Amphiuma (Fig. 7B) compare fa- vorably with those of extant Amphiuma pholeter (Fig. 7A) in their extremely small size, very low neural spine, and widely spaced but prominent anterior basapophyses. However, the fossils most likely represent a new species of the pan-pholeter lineage in having a more defined interzygapophy- seal ridge that is taller at the postzygapophyses than in extant A. pholeter examined, e.g., UF/H 152951 (Fig. 7A). This record is significant in that relatively little is known about extant A. pholeter and nothing has been previously published about its fossil record. It is understudied and seldom en- countered, has a restricted geographic range along the northeast border of the Gulf of Mexico Coastal Plain that includes the region where the Gragg fos- sils were collected, and is somewhat habitat spe- cific preferring deep liquid muck in floodplains of streams and rivers (Petranka, 1998; Bonett et al., 2009). Phylogenetically, A. pholeter has been re- covered as basal to other living amphiumas (Kar- lin and Means, 1994) or more recently as sister to Amphiuma means (Bonett et al., 2009). These fossils place the pan-pholeter lineage in the region for at least the past 14.8–14 million years. The fos- sil vertebrae of Notophthalmus (Fig. 7C–D) re- quire further study and comparisons to previously named Miocene species that include Notophthal- mus crassus (Hemingfordian, Batesland Forma- tion, South Dakota) (Tihen, 1974), Notophthalmus robustus (Hemingfordian, Thomas Farm, Florida) (Estes, 1963), and Notophthalmus slaughteri (ear- ly Barstovian, Trinity River Local Fauna, Texas) (Holman, 1966). SyMpatry oF aquatic LonG-Bodied SaLaManderS In discussing sympatry of aquatic long-bod- ied salamanders, the Gragg Mine caudate fauna is unusual for the southeastern Gulf Coastal Plain in that an amphiumid is present and a sirenid is not, most often the opposite holds true, or these gen- era co-occur in Miocene and other later Cenozo- ic deposits (JRB pers. observ.). It also represents one of the few co-occurrences of an amphiumid with Batrachosauroides. Other co-occurrences of amphiumids and batrachosauroidids are from the early Barstovian Moscow site, Polk County, Texas, and Arikareean 3 Toledo Bend locality in Newton County, Texas (Auffenberg, 1958; Albright, 1994; Holman, 1977; Holman, 2006). The Moscow site additionally preserved the co-occurrence of these two families and sirenids (Holman, 1977). Both the oldest and latest records of Batrachosauroides in Florida are from localities where Batrachosauroi- des co-occurs with Siren. Thomas Farm preserves the occurrence of Batrachosauroides and the spe- cies Siren hesterna (Goin and Auffenberg, 1955; Estes, 1963), and the Love Bone Bed preserves a co-occurrence of Batrachosauroides and a current- ly undescribed species of Siren. ACKNOWLEDGMENTS We thank C. Sheehey, M. C. Vallejo-Pareja, D. Blackburn (FLMNH), and J. C. Sagebiel (TMM) for collections assistance and discussions. R. Love and family allowed collecting on their property. J. Waldrop collected and donated the Suwannee Springs specimens. D. P. Mihalik provided access to Gragg Mine and donated specimens. J. Bloch, R. Narducci, and the Department of Natural History (FLMNH) provided funding for specimen scan- ning. D. Blackburn, R. Portell, and M. Kowalews- ki for editorial assistance and comments. K. Marks provided copy edits. J. Gardner (Royal Tyrrell Mu- seum of Paleontology) and R. Bonett reviewed the manuscript and provided helpful comments. Ad- ditionally, J. 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Trends, rhythms, and aberra- tions in global climate 65 Ma to present. Sci- ence 292:686–693. A1-1BOURQUE ET AL.: Late Miocene Batrachosauroides from Florida Unit number Floridaceras Menoceras Petauristodon 15 UF 90351* 7 UF 176197 UF 176195 6 UF 156149* 5 UF 90361 4 UF 185709* 2 UF 176199 UF 90353 1 UF 204153 UF 204154 Appendix 1: Table showing stratigraphic distribution of Floridaceras, Menoceras, and Petauristodon fos- sils recovered during 1981–1985 excavations at Thomas Farm. Units correspond to those of Pratt (1990); those without fossils of any of the three taxa are omitted. None of these taxa are particularly abundant at the site, so their absence in any particular stratum is not surprising. This is especially true for the absence of the two rhinos in Unit 15, as this bed contained relatively few fossils of larger taxa (Pratt, 1990). The stratigraphic distributions contradict the chronologic ranges given by Tedford et al. (2004) that would re- quire all records of Petauristodon to be from units above those with either of the two rhinos. *More than a single specimen found in this unit. A2-1BOURQUE ET AL.: Late Miocene Batrachosauroides from Florida S pe ci m en ID Sp ec ie s C ol le ct io n lo ca lit y V ox el re so lu tio n (m m ) vo lta ge (k V ) cu rr en t (µ A ) D et ec to r ca pt ur e (m S) pr oj ec tio n nu m be r Fi lte r M or ph oS ou rc e D O I U F: U F: 11 17 41 Ba tr ac ho sa ur oi de s s p. M ilw hi te G un n Fa rm M in e, F L 0. 02 18 95 03 10 0 25 0 20 0. 09 8 10 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 27 77 U F: U F: 20 13 Ba tr ac ho sa ur oi de s s p. M os co w lo ca lit y, B ur ke vi lle F au na , TX 0. 03 02 54 75 10 0 25 0 20 0. 09 8 80 0 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 27 76 U F: U F: 21 75 89 Ba tr ac ho sa ur oi de s s p. G ra gg M in e, G A 0. 03 02 54 75 10 0 25 0 20 0. 09 8 80 0 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 27 89 U F: U F: 29 38 02 Ba tr ac ho sa ur oi de s s p. Lo ve B on e B ed , F L 0. 02 18 95 03 10 0 25 0 20 0. 09 8 10 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 27 91 U F: U F: 54 64 55 Ba tr ac ho sa ur oi de s s p. Lo ve B on e B ed , F L 0. 00 50 60 56 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 04 U F: U F: 54 64 56 Am by st om a sp . Lo ve B on e B ed , F L 0. 00 27 20 16 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 05 U F: U F: 54 64 57 Am by st om a sp . Lo ve B on e B ed , F L 0. 00 33 86 95 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 18 U F: U F: 54 64 58 Am by st om a sp . Lo ve B on e B ed , F L 0. 00 31 99 58 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 19 U F: U F: 54 64 59 Si re n sp . Lo ve B on e B ed , F L 0. 00 30 44 26 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 33 U F: U F: 54 64 62 Si re n sp . Lo ve B on e B ed , F L 0. 00 55 21 09 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 34 U F: U F: 54 64 64 Si re n sp . Lo ve B on e B ed , F L 0. 00 40 32 91 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 47 U F: U F: 54 66 35 Ba tr ac ho sa ur oi de s s p. G ra gg M in e, G A 0. 00 50 58 9 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 48 U F: U F: 54 66 36 Am ph iu m a sp . G ra gg M in e, G A 0. 00 29 64 23 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 61 U F: U F: 54 66 43 N ot op ht ha lm us sp . G ra gg M in e, G A 0. 00 18 12 6 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 62 U F: U F: 54 66 44 N ot op ht ha lm us sp . G ra gg M in e, G A 0. 00 21 28 03 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 75 U F: U F: 54 66 53 Ba tr ac ho sa ur oi de s s p. G ra gg M in e, G A 0. 00 50 60 48 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 76 U F: U F: 78 02 Ba tr ac ho sa ur oi de s s p. Th om as F ar m , F L 0. 03 02 54 75 10 0 25 0 20 0. 09 8 80 0 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 89 U F: U F/ TR O :5 46 52 8 Ba tr ac ho sa ur oi de s s p. Su w an ne e Sp rin gs , FL 0. 01 57 86 75 80 20 0 25 0. 09 7 18 00 A l 0 .3 m m 10 .1 76 02 /M 2/ M 57 28 90 U F: U F/ TR O :5 46 52 9 Ba tr ac ho sa ur oi de s s p. Su w an ne e Sp rin gs , FL 0. 01 57 86 75 80 20 0 25 0. 09 7 18 00 A l 0 .3 m m 10 .1 76 02 /M 2/ M 57 29 01 U F: H er p: 15 29 51 Am ph iu m a ph ol et er Li be rty C ou nt y, F L 0. 00 29 64 27 60 20 0 25 0. 09 7 20 00 no ne 10 .1 76 02 /M 2/ M 57 26 27 S pe ci m en ID Sp ec ie s C ol le ct io n lo ca lit y V ox el re so lu tio n (m m ) vo lta ge (k V ) cu rr en t (µ A ) D et ec to r ca pt ur e (m S) pr oj ec tio n nu m be r Fi lte r M or ph oS ou rc e D O I U F: U F: 11 17 41 Ba tr ac ho sa ur oi de s s p. M ilw hi te G un n Fa rm M in e, F L 0. 02 18 95 03 10 0 25 0 20 0. 09 8 10 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 27 77 U F: U F: 20 13 Ba tr ac ho sa ur oi de s s p. M os co w lo ca lit y, B ur ke vi lle F au na , TX 0. 03 02 54 75 10 0 25 0 20 0. 09 8 80 0 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 27 76 U F: U F: 21 75 89 Ba tr ac ho sa ur oi de s s p. G ra gg M in e, G A 0. 03 02 54 75 10 0 25 0 20 0. 09 8 80 0 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 27 89 U F: U F: 29 38 02 Ba tr ac ho sa ur oi de s s p. Lo ve B on e B ed , F L 0. 02 18 95 03 10 0 25 0 20 0. 09 8 10 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 27 91 U F: U F: 54 64 55 Ba tr ac ho sa ur oi de s s p. Lo ve B on e B ed , F L 0. 00 50 60 56 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 04 U F: U F: 54 64 56 Am by st om a sp . Lo ve B on e B ed , F L 0. 00 27 20 16 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 05 U F: U F: 54 64 57 Am by st om a sp . Lo ve B on e B ed , F L 0. 00 33 86 95 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 18 U F: U F: 54 64 58 Am by st om a sp . Lo ve B on e B ed , F L 0. 00 31 99 58 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 19 U F: U F: 54 64 59 Si re n sp . Lo ve B on e B ed , F L 0. 00 30 44 26 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 33 U F: U F: 54 64 62 Si re n sp . Lo ve B on e B ed , F L 0. 00 55 21 09 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 34 U F: U F: 54 64 64 Si re n sp . Lo ve B on e B ed , F L 0. 00 40 32 91 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 47 U F: U F: 54 66 35 Ba tr ac ho sa ur oi de s s p. G ra gg M in e, G A 0. 00 50 58 9 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 48 U F: U F: 54 66 36 Am ph iu m a sp . G ra gg M in e, G A 0. 00 29 64 23 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 61 U F: U F: 54 66 43 N ot op ht ha lm us sp . G ra gg M in e, G A 0. 00 18 12 6 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 62 U F: U F: 54 66 44 N ot op ht ha lm us sp . G ra gg M in e, G A 0. 00 21 28 03 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 75 U F: U F: 54 66 53 Ba tr ac ho sa ur oi de s s p. G ra gg M in e, G A 0. 00 50 60 48 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 76 U F: U F: 78 02 Ba tr ac ho sa ur oi de s s p. Th om as F ar m , F L 0. 03 02 54 75 10 0 25 0 20 0. 09 8 80 0 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 89 U F: U F/ TR O :5 46 52 8 Ba tr ac ho sa ur oi de s s p. Su w an ne e Sp rin gs , FL 0. 01 57 86 75 80 20 0 25 0. 09 7 18 00 A l 0 .3 m m 10 .1 76 02 /M 2/ M 57 28 90 U F: U F/ TR O :5 46 52 9 Ba tr ac ho sa ur oi de s s p. Su w an ne e Sp rin gs , FL 0. 01 57 86 75 80 20 0 25 0. 09 7 18 00 A l 0 .3 m m 10 .1 76 02 /M 2/ M 57 29 01 U F: H er p: 15 29 51 Am ph iu m a ph ol et er Li be rty C ou nt y, F L 0. 00 29 64 27 60 20 0 25 0. 09 7 20 00 no ne 10 .1 76 02 /M 2/ M 57 26 27 S pe ci m en ID Sp ec ie s C ol le ct io n lo ca lit y V ox el re so lu tio n (m m ) vo lta ge (k V ) cu rr en t (µ A ) D et ec to r ca pt ur e (m S) pr oj ec tio n nu m be r Fi lte r M or ph oS ou rc e D O I U F: U F: 11 17 41 Ba tr ac ho sa ur oi de s s p. M ilw hi te G un n Fa rm M in e, F L 0. 02 18 95 03 10 0 25 0 20 0. 09 8 10 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 27 77 U F: U F: 20 13 Ba tr ac ho sa ur oi de s s p. M os co w lo ca lit y, B ur ke vi lle F au na , TX 0. 03 02 54 75 10 0 25 0 20 0. 09 8 80 0 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 27 76 U F: U F: 21 75 89 Ba tr ac ho sa ur oi de s s p. G ra gg M in e, G A 0. 03 02 54 75 10 0 25 0 20 0. 09 8 80 0 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 27 89 U F: U F: 29 38 02 Ba tr ac ho sa ur oi de s s p. Lo ve B on e B ed , F L 0. 02 18 95 03 10 0 25 0 20 0. 09 8 10 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 27 91 U F: U F: 54 64 55 Ba tr ac ho sa ur oi de s s p. Lo ve B on e B ed , F L 0. 00 50 60 56 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 04 U F: U F: 54 64 56 Am by st om a sp . Lo ve B on e B ed , F L 0. 00 27 20 16 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 05 U F: U F: 54 64 57 Am by st om a sp . Lo ve B on e B ed , F L 0. 00 33 86 95 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 18 U F: U F: 54 64 58 Am by st om a sp . Lo ve B on e B ed , F L 0. 00 31 99 58 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 19 U F: U F: 54 64 59 Si re n sp . Lo ve B on e B ed , F L 0. 00 30 44 26 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 33 U F: U F: 54 64 62 Si re n sp . Lo ve B on e B ed , F L 0. 00 55 21 09 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 34 U F: U F: 54 64 64 Si re n sp . Lo ve B on e B ed , F L 0. 00 40 32 91 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 47 U F: U F: 54 66 35 Ba tr ac ho sa ur oi de s s p. G ra gg M in e, G A 0. 00 50 58 9 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 48 U F: U F: 54 66 36 Am ph iu m a sp . G ra gg M in e, G A 0. 00 29 64 23 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 61 U F: U F: 54 66 43 N ot op ht ha lm us sp . G ra gg M in e, G A 0. 00 18 12 6 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 62 U F: U F: 54 66 44 N ot op ht ha lm us sp . G ra gg M in e, G A 0. 00 21 28 03 60 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 75 U F: U F: 54 66 53 Ba tr ac ho sa ur oi de s s p. G ra gg M in e, G A 0. 00 50 60 48 80 20 0 25 0. 09 7 20 00 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 76 U F: U F: 78 02 Ba tr ac ho sa ur oi de s s p. Th om as F ar m , F L 0. 03 02 54 75 10 0 25 0 20 0. 09 8 80 0 0. 1 m m C u 10 .1 76 02 /M 2/ M 57 28 89 U F: U F/ TR O :5 46 52 8 Ba tr ac ho sa ur oi de s s p. Su w an ne e Sp rin gs , FL 0. 01 57 86 75 80 20 0 25 0. 09 7 18 00 A l 0 .3 m m 10 .1 76 02 /M 2/ M 57 28 90 U F: U F/ TR O :5 46 52 9 Ba tr ac ho sa ur oi de s s p. Su w an ne e Sp rin gs , FL 0. 01 57 86 75 80 20 0 25 0. 09 7 18 00 A l 0 .3 m m 10 .1 76 02 /M 2/ M 57 29 01 U F: H er p: 15 29 51 Am ph iu m a ph ol et er Li be rty C ou nt y, F L 0. 00 29 64 27 60 20 0 25 0. 09 7 20 00 no ne 10 .1 76 02 /M 2/ M 57 26 27 A pp en di x 2: T ab le w ith h ig h- re so lu tio n C T da ta a nd sc an h yp er lin ks . U F sp ec im en s d is pl ay ed u si ng D ar w in C or e T rip le t i de nt ifi er sc he m e. https://doi.org/10.17602/M2/M572777 https://doi.org/10.17602/M2/M572776 https://doi.org/10.17602/M2/M572789 https://doi.org/10.17602/M2/M572791 https://doi.org/10.17602/M2/M572804 https://doi.org/10.17602/M2/M572805 https://doi.org/10.17602/M2/M572819 https://doi.org/10.17602/M2/M572818 https://doi.org/10.17602/M2/M572833 https://doi.org/10.17602/M2/M572834 https://doi.org/10.17602/M2/M572847 https://doi.org/10.17602/M2/M572848 https://doi.org/10.17602/M2/M572861 https://doi.org/10.17602/M2/M572862 https://doi.org/10.17602/M2/M572875 https://doi.org/10.17602/M2/M572876 https://doi.org/10.17602/M2/M572889 https://doi.org/10.17602/M2/M572890 https://doi.org/10.17602/M2/M572627 https://doi.org/10.17602/M2/M572901