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1. Paleogene Echinoids of Florida

   https://doi.org/10.58782/flmnh.xqds7462  

   Osborn, Adam S; Portell, Roger W; Mooi, Rich (February 2025, Bulletin of the Florida Museum of Natural History)

   Sixty-five species and nine indeterminate taxa of Florida Paleogene echinoids are discussed, and their geographic and stratigraphic distributions provided. These include 49 species documented from the Eocene and 16 from the Oligocene. Ten new species are described: Prionocidaris robertsi n. sp., Rhyncholampas mariannaensis n. sp., Rhyncholampas bao n. sp., Weisbordella inglisensis n. sp., Weisbordella libum n. sp., Durhamella tetrapora n. sp., and Brissus jonesi n. sp. from the Eocene; and Plagiobrissus cassadyi n. sp., Eupatagus dumonti n. sp., and Schizaster carlsoni n. sp. from the Oligocene. We reconsidered subjective junior synonyms of all species and resurrect Neolaganum archerensis, Echinocyamus macneili, and Eupatagus mooreanus. Furthermore, we updated the taxonomy for all included species and their known distributions and provide emended diagnoses for the genera and species of Florida Neolaganidae. In addition, we herein report the occurrence of Porpitella micra in Cretaceous strata of the subsurface of Florida. This remarkable finding makes P. micra the earliest known of all the scutelloids. Echinoids within the Ocala Limestone are placed in five echinoid biozones, which are defined within, these include the Oligopygus phelani, Oligopygus haldemani, Oligopygus wetherbyi, Wythella eldridgei, and Haimea brooksi Zones. This document complements the Neogene (including the Quaternary) fossil echinoid fauna of Florida we published in 2020 and represents a compilation of the known Florida Paleogene echinoid record. The region is currently known to have the most speciose and diverse assemblage of Paleogene echinoids in the United States. 

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2. Site U1450

   https://doi.org/10.14379/iodp.proc.354.104.2016  

   France-Lanord, C; Spiess, V; Klaus, A; Adhikari, RR; Adhikari, SK; Bahk, J-J; Baxter, AT; Cruz, JW; Das, SK; Dekens, P; et al (September 2016, Proceedings of the International Ocean Discovery Program Expedition reports)

   Site U1450 (proposed Site MBF-2A) occupies a central position at 8°0.42′N and 87°40.25′E in the east–west transect across the Bengal Fan at 8°N. It is located at equal distance from Site U1451 on the flank of the Ninetyeast Ridge and Site U1455 on the flank of the 85°E Ridge. The overall thickness of the fan reaches ~4 km at this location (Curray et al., 2003). Neogene sediment thickness decreases toward the two ridges, which is likely the result of ongoing deformation on both ridges during the Neogene (Schwenk and Spiess, 2009). At this central position of the transect, the upper Miocene and Pliocene–Pleistocene sections of the fan appear to be most expanded and are inferred to contain a higher resolution record, as well as accumulating, on average, coarser grained material. The shallow section at this site is one of the seven ~200 m deep sections along the 8°N transect that constrain the Middle Bengal Fan architecture in space, time, and sediment delivery rate during the Pleistocene. The deeper section at this site will document the delivery mechanisms of the fan and the climatically and tectonically influenced sediment supply from the Himalaya during the Neogene. Changes in the source regions in response to tectonic and climatic evolution of the Himalaya are expected to be reflected in the sediment’s mineralogical and geochemical compositions, the geochronological data, and in accumulation rates across the transect. 

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3. Site U1455

   https://doi.org/10.14379/iodp.proc.354.109.2016  

   France-Lanord, C; Spiess, V; Klaus, A; Adhikari, RR; Adhikari, SK; Bahk, J-J; Baxter, AT; Cruz, JW; Das, SK; Dekens, P; et al (September 2016, Proceedings of the International Ocean Discovery Program Expedition reports)

   Site U1455 (proposed Site MBF-1A) is the last site drilled during Expedition 354 in the Bengal Fan. It is a reoccupation of Deep Sea Drilling Project (DSDP) Site 218 (see Figure F11 in the Expedition 354 summary chapter [France-Lanord et al., 2016e]) (von der Borch, Sclater, et al., 1974), which was the first attempt to drill the Bengal Fan and was only spot cored with the rotary core barrel (RCB) system to 773 meters below seafloor (mbsf). The site is above the eastern flank of the 85°E Ridge at 8°0.42′N, 86°16.97′E at 3743 m water depth. Site U1455 is one of three deep-penetration sites along the Expedition 354 transect dedicated to reveal Neogene fan evolution and Himalayan erosion. This site will also document Pleistocene fan architecture when integrated into the complete seven-site transect. Coring to 900 mbsf was planned to determine Miocene to Pliocene accumulation rates and changes related to Himalayan erosion and environment. The deeper part of the site will extend the existing Site 218 record back into the middle Miocene. Because of time constraints at the end of the expedition, we focused coring on three objectives: the Pleistocene (0–122 mbsf), the late Miocene terrestrial vegetation transition from C3 to C4 plants (360–431 mbsf), and the middle Miocene (773–949 mbsf) to extend the existing core record of Site 218. 

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4. Neogene precipitation, vegetation, and elevation history of the Central Andean Plateau

   https://doi.org/10.1126/sciadv.aaz4724  

   Martínez, C.; Jaramillo, C.; Correa-Metrío, A.; Crepet, W.; Moreno, J. E.; Aliaga, A.; Moreno, F.; Ibañez-Mejia, M.; Bush, M. B. (August 2020, Science Advances)

   null (Ed.)

   Andean uplift played a fundamental role in shaping South American climate and species distribution, but the relationship between the rise of the Andes, plant composition, and local climatic evolution is poorly known. We investigated the fossil record (pollen, leaves, and wood) from the Neogene of the Central Andean Plateau and documented the earliest evidence of a puna-like ecosystem in the Pliocene and a montane ecosystem without modern analogs in the Miocene. In contrast to regional climate model simulations, our climate inferences based on fossil data suggest wetter than modern precipitation conditions during the Pliocene, when the area was near modern elevations, and even wetter conditions during the Miocene, when the cordillera was around ~1700 meters above sea level. Our empirical data highlight the importance of the plant fossil record in studying past, present, and future climates and underscore the dynamic nature of high elevation ecosystems. 

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5. The rises and falls of turritellid gastropods during the Cenozoic in the western Atlantic

   Allmon, WD; Anderson, BM (July 2024, Museum of Paleontology, The University of Michigan; Papers on Paleontology)

   and frequently-occurring marine macrofossil groups of the past 100+ million years worldwide. From their apparent origin in central Tethys in the late Jurassic they spread across most of the world’s oceans by the Late Cretaceous. They suffered substantial extinction at the K-Pg but diversified quickly thereafter, and they were present on every continent during the Paleogene. The record of their diversity, abundance, and morphology during the Cenozoic has become clearer due to recent studies of body size, molecular phylogenetic analysis, and systematic treatments of Paleogene, Miocene, and Plio-Pleistocene fossils from the Western Atlantic region (southeastern North America, the Caribbean, Central America, and northern South America). A database (still a work in progress) of more than 230 described species from this region shows turritellid diversity of more than 20 species in the Paleocene, a low of fewer than 10 in the early Eocene, a peak of more than 80 in the Miocene, a decline to around 20 in the Pliocene, and a decline to only 4 species in the central Western Atlantic today. Diversity within single formations shows a slightly different pattern, with highs of 11–16 species in the Late Miocene of Colombia and 18 species in the Late Pliocene Pinecrest Sand of Florida. Overall abundance has also declined, with turritellid-dominated assemblages common across the region throughout the Cenozoic, but limited today to only small areas of northern Venezuela. Higher taxonomic assignments of fossil and Recent turritellids and their phylogenetic relationships are still poorly known (and are likely to remain so for many species), but recent molecular data and systematic work on fossil turritellids indicate that several clades (e.g., Torcula) persisted in the region throughout the Cenozoic, while other groups which became significant likely appeared in the Miocene, including Vermicularia and Caviturritella. A common pattern in all of this change is correlation with likely patterns of primary productivity. Hyperdiverse assemblages and high regional diversity of turritellids appear to occur at times and places of high productivity, frequently in association with upwelling or significant terrestrial runoff, and patterns of extinction (temporal and geographic) correlate with declines in productivity. Funding source: NSF DEB 2225014 

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