Bone Valley Formation Research Articles

Pygmy sperm whales (Odontoceti, Kogiidae) from the Pliocene of Florida and North Carolina

ABSTRACTWe describe fossil kogiid periotics from the Lower Pliocene upper Bone Valley Formation in central Florida and the Lower to Upper Pliocene Yorktown Formation at Lee Creek Mine, North Carolina. The fossils show diagnostic characters that identify them as belonging to Kogiidae, such as three spines in the anterior process, presence of an incudal process, and a posterior process oriented along the long axis of the bone. Morphological comparisons and morphometric and statistical analyses of periotic proportions confirm the presence of a large and a small morphotype within the sample. The large morphotype (mean length = 39.76 mm) belongs to an unknown kogiid that occurs in both formations, whereas the small morphotype (mean length = 28.64 mm), referred to aff. Kogia sp., occurs only in the Yorktown Formation. The cooccurrence of two taxa in North Carolina may represent one of the earliest evidences of sympatry in kogiids and may demonstrate that this ecological behavior has been part of the natural history of this group at least since the deposition of the Yorktown Formation at Lee Creek (∼4.8–3.1 Ma). In addition, the occurrence of the large morphotype in the upper Bone Valley Formation, herein reported for the first time, shows that we are still far from understanding the diversity of marine mammals of that formation and that revision of newly acquired material is necessary.SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVPCitation for this article: Vélez-Juarbe, J., A. R. Wood, and C. Pimiento. 2016. Pygmy sperm whales (Odontoceti, Kogiidae) from the Pliocene of Florida and North Carolina. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2016.1135806.

A Machairodont felid (Mammalia; Carnivora; Felidae) from the latest Hemphillian (Late Miocene/Early Pliocene) Bidahochi Formation, northeastern Arizona

A lower jaw from the White Cone local fauna of the latest Hemphillian Bidahochi Formation in northern Arizona is the first description of a felid from this fauna and the first positively identified occurrence of the smilodontine machairodont Paramachairodus in North America. This lower jaw has characters identical to those seen in a similar sized machairodont felid from the Bone Valley Formation of Florida, suggesting that the same taxon is present in Florida. The diversity of the Hemphillian machairodonts and the taxonomic status of Megantereon hesperus is reviewed. The characteristics of the ramus corpus and dentition places Paramachairodus firmly within the Smilodontini and adds further support that the more derived smilodontine machairodonts, Megantereon and Smilodon, had their origins in North America.

Fossil Sirenia of the West Atlantic and Caribbean region. VIII. Nanosiren garciae, gen. et sp. nov. and Nanosiren sanchezi, sp. nov.

The new dugongine dugongid Nanosiren garciae is the third species of fossil sirenian to be described from the Bone Valley phosphate deposits of Florida. It is found in the Upper Bone Valley Formation and is of latest Hemphillian (early Pliocene) age. Nanosiren sanchezi is described from the late Miocene upper member of the Urumaco Formation, Falcón State, Venezuela. It appears to be directly ancestral to N. garciae, and was preceded in the West Atlantic, Caribbean, and East Pacific region by other, undescribed members of the same generic lineage dating back at least to the early Miocene. The Nanosiren lineage is the most basal clade of the Subfamily Dugonginae after Crenatosiren olseni, and is the sister group to all remaining dugongines. It comprises the smallest known post-Eocene sirenians, with adult body lengths and weights probably around 2 m and 150 kg. Newborn animals may have had body masses little greater than the theoretical limit of 6.8 kg for a viable aquatic endotherm. In addition to a shallow draft, Nanosiren spp. had small conical tusks and strong rostral deflections. These characters possibly indicate that they foraged in shallower water than the larger dugongids with which they were sympatric, such as Metaxytherium (a rib from Urumaco probably referable to this genus is also recorded here). Nanosiren probably fed in nearshore marine waters on small seagrasses such as Halodule and Halophila.

ON THE PRESENCE OF MEGANTEREON WHITEI AT THE SOUTH TURKWEL HOMINID SITE, NORTHERN KENYA

Werdelin and Lewis (2000) recently described a new species of the saber-tooth genus Megantereon (Mammalia, Carnivora, Felidae) from Late Pliocene (∼3.5 Ma) deposits of the Nachukui Formation south of the Turkwel River in Turkana, northern Kenya (Ward et al., 1999). The new species, Megantereon ekidoit , is said to represent the earliest occurrence of this genus in Africa. It was described from a right mandibular ramus (KNM-St 23812) with i3–m1. As discussed below, the post-canine diastema is longer than the cheek-tooth row, since there does not appear to have been a third premolar (p3), and the coronoid process is relatively well developed, showing a hook-shaped morphology (Werdelin and Lewis, 2000: Fig. 1). The fourth premolar (p4) and the lower carnassial tooth (m1) show considerable wear. Figure 1 —Scatter-plot of 1, lower carnassial length (Lm1) and lower fourth premolar length (Lp4), and 2, lower fourth premolar length and width (Wp4) for specimens of Megantereon (Eurasian and North American M. cultridens , African M. whitei ; data from Turner, 1987; Martinez-Navarro and Palmqvist, 1995, 1996). The corresponding measurements for mandible KNM-St 23812, the holotype of M. ekidoit , are also shown (data from Werdelin and Lewis, 2000) Two major reviews on the origin, evolution and dispersal of Megantereon have been published by Turner (1987) and by Martinez-Navarro and Palmqvist (1995), respectively; surprisingly, neither of these articles were cited by Werdelin and Lewis (2000). The saber-tooth genus Megantereon shares much in common with Smilodon , and both genera form the tribe Smilodontini. The earliest presence of Megantereon is recorded at 4.5 Ma in the Bone Valley Formation (Florida), where it is represented by Megantereon cultridens . This species dispersed from North America before 3.5 Ma, to extend all over the Old World. Europe was also home to …

Overview of the geology and vertebrate biochronology of the Leisey Shell Pit Local Fauna, Hillsborough County, Florida

Overview of the geology and vertebrate biochronology of the Leisey Shell Pit Local Fauna, Hillsborough County, Florida

Fossil Sea Turtles from the Early Pliocene Bone Valley Formation, Central Florida

Four genera of cheloniid (Caretta, Chelonia, Eretmochelys, Lepidochelys) and one genus of dermochelyid (Psephophorus) sea turtles are recorded from the Bone Valley Formation of central Florida. The fossils derive from phosphate deposits of early Pliocene (late Hemphillian) age, 4.5-5 Ma. Although similar in age to fossils from the Yorktown Formation (Lee Creek Mine) in North Carolina, the Bone Valley sea turtle fauna appears to lack two genera found at Lee Creek (Syllomus, Procolpochelys) and contains one genus that is not found at Lee Creek (Eretmochelys). The Caretta from the two areas may not be conspecific. The fossil Chelonia, Eretmochelys, and Lepidochelys cannot be distinguished confidently from modern species, but conversely only the Lepidochelys appears obviously related to a particular modern species, L. kempi. This paper provides the first report of Eretmochelys in Pliocene deposits and the first association of Psephophorus with all living cheloniid genera except the Australian Natator. We suggest that shallow seas in the Bone Valley region provided rich feeding habitat for sea turtles in the early Pliocene in the same way that shallow water habitats in Florida and the Bahamas support a similar assemblage today. The Bone Valley phosphate mining region of central Florida long has been known as a rich source of terrestrial and marine vertebrate fossils (Sellards, 1916; Allen, 1921; Simpson, 1930; Kellogg, 1944; Brodkorb, 1955). Phosphatic sediments of the Bone Valley Formation in this region have produced a sequence of vertebrate faunas dating from the middle Miocene (about 16 Ma) to the early Pliocene (4.5 Ma) (Webb and Hulbert, 1986). The best known Bone Valley fauna is early Pliocene in age and has been referred to the late Hemphillian North American Land Mammal Age (NALMA; Berta and Morgan, 1985; Webb and Hulbert, 1986; Tedford et al., 1987). Following Webb and Hulbert (1986), we use the term Palmetto Fauna to distinguish the late Hemphillian vertebrate assemblage from older faunas present in the Bone Valley region. The Palmetto Fauna contains a fossil assemblage representing marine, estuarine, freshwater, and terrestrial components, and appears to have accumulated at a time when sea levels were about 50 m higher than present (Webb and Tessman, 1968; MacFadden and Webb, 1982). The marine and estuarine components consist of sharks, rays, bony fish, sea turtles, pelagic birds, and many marine mammals, including a walrus, three species of seals, a sea otter, a sea cow, and numerous cetaceans (Berta and Morgan, 1985). The presence of sea turtles in late Hemphillian age deposits in the Bone Valley region was noted briefly by Berta and M rgan (1985) and Dodd (1990), but these fossils have not been previously described. Tertiary sea turtle fossils have been described from a number of localities on the Atlantic Coastal Plain, including the Paleocene Hornerstown Sand and Vincetown Formation and Eocene Manasquan Formation of New Jersey (Weems, 1988), the Paleocene Brightseat and Aquia Formations of Maryland and Virginia (Weems, 1988), the Oligocene Ashley Formation of South Carolina (Hay, 1923), the Miocene Kirkwood Formation of New Jersey (Zangerl and Turnbull, 1955; Weems, 1974), the Miocene Calvert Formation of Maryland and Virginia (Weems, 1974, 1980), and the Pliocene Yorktown Formation in North Carolina (Zug, in press). The very few published records of Tertiary sea turtles from the Gulf Coastal Plain include a questionable Eocene dermochelyid from Alabama (Thurmond and Jones, 1981) and a middle Eocene cheloniid from Florida (P. Meylan, 1984). There also are some unreported cheloniid fossils from Florida, mostly consisting of shell fragments, from the middle Eocene Avon Park Limestone and Inglis Formation and the Oligocene Suwannee Limestone (G. Morgan, unpubl. obs.). A few Florida Pleistocene fragments belonging to modern genera (Chelonia, Caretta) were mentioned by Hay (1916, 1917), but no comprehensive summary or description of these fossils is available. One of the largest collections of Tertiary sea turtle fossils in North America is from the Lee This content downloaded from 157.55.39.224 on Sat, 27 Aug 2016 04:05:15 UTC All use subject to http://about.jstor.org/terms C. K. DODD, JR. AND G. S. MORGAN

TVA pilot-plant phosphate flotation conditioning study

TVA conducted an extensive test program in its 1,000-pound-per-hour phosphate beneficiation pilot plant to study the effects of major variables in the conditioning step prior to phosphate flotation. Florida rock fine flotation feeds of 14 and 18 bone phosphate of lime (BPL) from the Bone Valley formation were tested. During Phase I for each flotation feed, a full factorial design was used for the test series to evaluate the effects of agitation, retention time, and solids content on P2O5 recovery and product grade. In Phase II, a qualitative test study was completed of several additional variables including agitator flow direction, slurry feed position, use of baffles or no baffles, fuel oil to fatty acid ratio, and reagent dosage. The results of both test series were statistically analyzed and compared with those obtained from batch, laboratory-scale flotation tests of pilot plant conditioned samples. From the pilot-scale results, a mathematical model was developed relating product grade and P2O5 recovery to the major process variables.

Fossil Sirenia of the West Atlantic and Caribbean region. I.Metaxytherium floridanumHay, 1922

ABSTRACT The vast majority of the abundant fossil sirenian remains from the Bone Valley phosphate mining district (chiefly in Polk and Hillsborough counties, Florida) represent a single species of dugongid, Metaxytherium floridanum Hay, 1922. The osteology of this species is described here in detail. Most or all of these specimens apparently come from Units 4–5 of the lower Bone Valley Formation and are late middle Miocene (early Clarendonian) in age. M. ossivallense (Simpson, 1932) is a junior subjective synonym of M. floridanum. M. calvertense Kellogg, 1966, and “Hesperosiren” Simpson, 1932, are not represented in the Bone Valley Formation. Specimens are also reported here from elsewhere in Florida, mainly Alachua County. Some or all of these are later than the typical Bone Valley form, being of late Clarendonian or early Hemphillian age, and some of them, here termed Metaxytherium, cf. M. floridanum, seem to represent a slightly more advanced stage of evolution. M. floridanum had a strongly deflected rostrum adapted to bottom-feeding and very small, subconical, enameled tusks. It is practically indistinguishable from the contemporaneous M. medium of western Europe; however, the recency of their common ancestry remains to be clarified. Apparently M. floridanum was endemic to the West Atlantic and became extinct without issue by the end of the Miocene.

Late Hemphillian monodactyl horses (Mammalia, Equidae) from the Bone Valley Formation of central Florida

Isolated cheek teeth of the hypsodont one-toed horses Astrohippus stocki and Dinohippus mexicanus are described from ten localities within the classic vertebrate-bearing beds of the Bone Valley phosphate mining district and one new locality (containing the Lockwood Meadows Local Fauna) in Sarasota, Florida. All occurrences of these taxa are from the upper Bone Valley Formation and further confirm a late Hemphillian (late Miocene to early Pliocene) age, or within the range of about 5.4 to 4.5 myBP for this part of the sedimentary sequence. In contrast to the common occurrences of hipparions in the Bone Valley Formation, A. stocki and D. mexicanus are relatively rare. In some dental charcters such as protocone length and crown height, A. stocki and D. mexicanus are no more advanced in their stage of evolution than the advanced three-toed horses Neohipparion eurystyle, N. gidleyi and Nannippus peninsulatus.

A Miocene amphicyonid (Mammalia: Carnivora) from the Bone Valley Formation of Florida

ABSTRACT A mandibular ramus referred to a new amphicyonid species Pliocyon robustus is described from the Bone Valley Formation of Florida. This is the first reported occurrence of Pliocyon from eastern North America. Pliocyon robustus differs from the genotype, Pliocyon medius, in a number of characters that include: larger size, deeper and more robust jaw, extremely reduced P2–3, and P2 larger than P3. The Florida occurrence of Pliocyon indicates the presence of older medial Miocene (either Barstovian or Clarendonian) deposits within the Bone Valley Formation.

PrimitiveMylohyus(Artiodactyla: Tayassuidae) from the late Hemphillian Bone Valley of Florida

ABSTRACT The first skull and an additional mandible of Prosthennops elmorei White are described and the species is transferred to Mylohyus Cope on the basis of several derived characters including molariform premolars, post-canine diastema length greater than length of cheek tooth series, and posterior position of the orbit. A distinctive feature of this species is its laterad projecting, inflated triangular zygomatic process. In other known Mylohyus skulls (all from the Pleistocene) the zygoma is not expanded into a laterad projecting process, but is inflated anterior to the glenoid fossa and its ventral surface provides a broad origin for M. masseter lateralis. The wing-like zygomata of M. elmorei are probably primitive for Mylohyus. M. elmorei occurs in the upper member of the Bone Valley Formation of Florida. On the basis of associated taxa it is very late Hemphillian (early Pliocene) in age. Thus it is the oldest known species of Mylohyus and more than doubles the antiquity of that genus.

Kyptoceras amatorum, new genus and species from the Pliocene of Florida, the last protoceratid artiodactyl

ABSTRACT Kyptoceras amatorum n.g. et sp. is described from the Upper Bone Valley Formation, late Hemphillian (early Pliocene) of Polk County, Florida. In the male skull the forked rostral horn lacks a shaft and the frontal horns are nearly twice as long as those of any other Protoceratidae. Both the rostral and the frontal horns are tilted forward in distinctive fashion. This genus represents a new tribe, Kyptoceratini, which may have originated in subtropical savannas south of the range of the more familiar tribe Synthetoceratini.

Geochemical Mechanics for the Dissolution, Transport, and Deposition of Aluminum in the Zone of Weathering

AbstractOrganic acids in the 0·01M concentration range representing amino-, aliphatic, and aromatic types present in humus dissolve 70–85 ppm Al from Arkansas bauxite at room temperature, whereas 0-03 ppm is dissolved in water. The species of Al in aqueous solution, calculated from stability data, range from Al3+ at pH 3 and lower, through Al2(OH)24+ at a maximum concentration at pH 4·5, Al(OH)2+ at a maximum at pH 4·7, Al(OH)2+ at a maximum at pH 60, to Al(OH)4- at pH 8·5 and higher. In salicylic acid an Al-Sal+ complex occurs between pH 1·5 and 8·5, and is at a maximum at pH 4·2. Solubility of Al obviously is pH dependent; also because of the vulnerability of organic acids to oxidation, the solubility and transport of Al is indirectly Eh dependent. Anions that combine with Al include OH- to form bauxite, PO43- to form lateritic phosphate such as the Bone Valley Formation, Fla., and SiO44- to form allophane or kaolin as noted in the kaolin synthesis by Linares and Huartes. Spongelike, pisolitic or oolitic structures, and mineral veins in bauxites, lateritic phosphates, and some flint clays attest to mobilization of Al in solution. Lignites and humus zones associated with latentes are a logical geologic source of these complexing organic solvents. Although Al is inherently mobile, such commonly available precipitating anions render Al relatively immobile.

The Pliocene Canidae of Florida

A new genus and species of canid, Carpocyon limosus is described from the Hemphillian (Middle Pliocene) Bone Valley Formation. Though showing strong omnivorous tendencies, it is not closely related to cynarctine canids; nor is it close to Actiocyon Stock which is here synonymized with Alopecocyon Camp and Vanderhoof. Carpocyon cuspidatus (Thorpe), new combination, from the late Barstovian (Late Miocene) of Nebraska, represents an earlier stage of evolution and suggests derivation of Carpocyon from Tomarctus. Five species of Osteoborus are now known from Florida: (1) Osteoborus dudleyi (White), new combination, is a large, progressive species from the Bone Valley fauna. Pliogulo White is considered a synonym of Osteoborus Stirton and Vanderhoof. Osteoborus crassapineatus Olsen is placed in synonymy with O. dudleyi (White). (2) O. orc, new species, is a very small but advanced form from Withlacoochee River site 4A; and two less progressive species occur together in Mixson's Bone Bed, (3) O. galushai, a new medium-sized species, near O. cyonoides, and (4) a very large species near O. validus. The latter also occurs at McGehee Farm. (5) A species larger and even more primitive than O. galushai also occurs at MeGehee Farm and at Hogtown Creek site II. Until it can be characterized by more adequate material, it is referred to O. galushai.

The heavy minerals of the Bone Valley Formation and their potential value

The heavy minerals of the Bone Valley Formation and their potential value