{"title":"Muroid rodents from the Lower Siwalik deposits near Ramnagar (Jammu and Kashmir), India: Biostratigraphic implication","authors":"Varun Parmar , Rigzin Norboo , Deepak Singh Kshetrimayum , Rahul Magotra","doi":"10.1016/j.geobios.2024.12.003","DOIUrl":"10.1016/j.geobios.2024.12.003","url":null,"abstract":"<div><div>Various Lower Siwalik localities within the Ramnagar basin in Northwestern Jammu Himalaya (India) are known to yield diverse Miocene fossil mammals. However, as neither magnetostratigraphic ages nor radiometric dates are available, absolute temporal constraints on the fossiliferous horizons are missing. Some age diagnostic fauna recorded from the Ramnagar area has been utilized to date some fossil productive horizons such as Kalaunta 2 (K2), Dehari 1 (D1), Dehari 2 (D2), and Basi. In the present work murine dentition recovered from the Lower Basi (LB) site is reported. Based on the micromammalian assemblage at K2, D1 and LB, the fossiliferous horizons are placed in a composite stratigraphic column of the Ramnagar Basin. Variation of micromammalian content across these three fossiliferous horizons document dominance of cricetid rodents and absence of rhizomyine rodents at K2 site, abundance of rhizomyine rodents and scarcity of cricetid rodents at D1 site, and absence of cricetids rodents but presence of rhizomyine and murine rodents in the LB site.</div></div>","PeriodicalId":55116,"journal":{"name":"Geobios","volume":"91 ","pages":"Pages 89-101"},"PeriodicalIF":1.6,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144314654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
GeobiosPub Date : 2025-05-22DOI: 10.1016/j.geobios.2024.12.004
Orangel Aguilera , Carlos de Gracia , Félix Rodriguez , Olga Oliveira de Araújo , Werner Schwarzhans , Philippe Béarez , Antoni Lombarte , Paulo Andreas Buckup , Ricardo Tadeu Lopes
{"title":"Fossil moray eels (Muraenidae) from the interoceanic Central American seaway","authors":"Orangel Aguilera , Carlos de Gracia , Félix Rodriguez , Olga Oliveira de Araújo , Werner Schwarzhans , Philippe Béarez , Antoni Lombarte , Paulo Andreas Buckup , Ricardo Tadeu Lopes","doi":"10.1016/j.geobios.2024.12.004","DOIUrl":"10.1016/j.geobios.2024.12.004","url":null,"abstract":"<div><div>Despite the wide distribution and diversity of extant Anguilliformes in tropical America (central western Atlantic and central eastern Pacific), no fossil moray ell (Muraenidae) has been reported to date from this region. Here, we describe the first three fossil specimens of Muraeninae from America: one from the Late Miocene Gatun Formation (Fm.), the second from the Late Pliocene Escudo de Veraguas Fm., both from Panama, and the third from the Late Pliocene Rio Banano Fm. in Costa Rica. <em>Gymnothorax pierreolivieri</em> nov. sp. from the Gatun Fm. is described based on the skull and an <em>in situ</em> otolith. The new species is characterized by a premaxilla-ethmo-vomerine bone (PMx-Etv) with 15 marginal fang-like teeth, two medial teeth, and 13 vomerine teeth arranged in a single row. The dorsal stem of the PMx-Etv forms a very thick and massive structure, with a single anterior foramen located in the anterior tip of the bone. The maxilla has 16 teeth arranged in a double row. The sagitta otolith is elliptic and tapered anteriorly; its posterior margin is smooth and gently rounded; its dorsal margin is slightly arched and elevated posteriorly. The isolated otoliths from the Escudo de Veraguas Fm. in Panama and from the Rio Banano Fm. in Costa Rica are putatively assigned to <em>Echidna</em> sp. and <em>Enchelycore</em> sp., respectively. The diversification of American Muraenidae seems to have been driven by oceanic water interchanges and species dispersal associated to marine currents that flowed eastward through the Central American Seaway prior to the total closure of the Panama Isthmus. The extant American muraenid diversity illustrates allopatric speciation (vicariance) when populations from the Atlantic and the Pacific oceans were isolated by the late Tertiary uplift of the Isthmus of Panama. The palaeoceanographic changes driven by this geological event have had evolutionary consequences on faunal turnover and extinctions through space and time and is reflected by the extant fish diversity.</div></div>","PeriodicalId":55116,"journal":{"name":"Geobios","volume":"91 ","pages":"Pages 21-41"},"PeriodicalIF":1.6,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144314650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
GeobiosPub Date : 2025-05-22DOI: 10.1016/j.geobios.2024.11.011
Z. Jack Tseng , Xiaoming Wang
{"title":"Borophagine canids of the Monarch Mill Formation (Middle Miocene), Nevada, U.S.A.","authors":"Z. Jack Tseng , Xiaoming Wang","doi":"10.1016/j.geobios.2024.11.011","DOIUrl":"10.1016/j.geobios.2024.11.011","url":null,"abstract":"<div><div>The non-marine Middle Miocene Monarch Mill Formation (Nevada, U.S.A.) outcrops in the Middlegate Basin and preserves fossil mammals that lived during the establishment of the present-day basin and range topography in central Nevada. The Monarch Mill Formation and its mammal fauna overlie the Middlegate Formation and its flora, and together the biota provides an informative window into ecosystem composition at the geographic crossroads between the Great Plains and the coastal regions of North America during the Middle Miocene. Here we report on previously undescribed and/or unfigured canids from the Monarch Mill Formation. To the previously known borophagine <em>Tomarctus brevirostris</em> and the fox-like canine <em>Leptocyon</em> we add two borophagine genera to the Eastgate Local Fauna of the Monarch Mill Formation. Specimens of the hypocarnivores <em>Paracynarctus</em> and <em>Cynarctus</em> are described and provide an enhanced understanding of the Middlegate Basin canid assemblage, now comprising at least four genera. Together with floral evidence, this canid assemblage is indicative of mesocarnivore-sustaining vegetation and locally limited open environments, with no hypercarnivorous canid occurrences. Rapid regional subsidence was an overarching factor in the shift towards present-day hyper- and meso-carnivore dominated canid assemblages in the Basin and Range Province, and the appearance of hypercarnivores in post-Barstovian times may reflect contemporaneous regional topographic shifts in the Great Basin at large.</div></div>","PeriodicalId":55116,"journal":{"name":"Geobios","volume":"91 ","pages":"Pages 11-19"},"PeriodicalIF":1.6,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144154794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
GeobiosPub Date : 2025-05-22DOI: 10.1016/j.geobios.2024.12.002
Jean-Michel Mazin, Joane Pouech
{"title":"Diversity of the pterodactyloid ichnites of Crayssac (Lower Tithonian, Late Jurassic, southwestern France)","authors":"Jean-Michel Mazin, Joane Pouech","doi":"10.1016/j.geobios.2024.12.002","DOIUrl":"10.1016/j.geobios.2024.12.002","url":null,"abstract":"<div><div>The ichnosite of Crayssac (Upper Jurassic, southwestern France) yields numerous vertebrates and invertebrates trackways, among which the pterodactyloid pterosaur trackways are frequent. One hundred and sixty nine vertebrate trackways (turtles, crocodilians, dinosaurs and pterosaurs) have been unearthed by our team. They are preserved <em>in situ</em>, are sheltered by a building and legally protected within the Réserve Naturelle Nationale Géologique du Lot<em>.</em> Among these vertebrate trackways, sixty-four can be attributed to tiny- to medium-sized pterodactyloids, representing five morphotypes referred to five new ichnospecies: Morphotype I, <em>Pteraichnus occitanis</em> (1 specimen); Morphotype II, <em>Pteraichnus cadurcii</em> (12 specimens); Morphotype III, <em>Pteraichnus communis</em> (21 specimens); Morphotype IV, <em>Pteraichnus dichnopollex</em> (10 specimens); and Morphotype V, <em>Pteraichnus pyrenaicus</em> (7 specimens)<em>.</em> These trackways are finely preserved and represent a unique, abundant and diversified sample. Study of complete trackways rather than isolated footprints allows access to important parameters such as the velocity or the comparative gauges. Similarly, the orientation of all vertebrate trackways shows that the pterosaurs moved actively across the mudflat, without preferred direction.</div></div>","PeriodicalId":55116,"journal":{"name":"Geobios","volume":"91 ","pages":"Pages 61-79"},"PeriodicalIF":1.6,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144314652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
GeobiosPub Date : 2025-05-22DOI: 10.1016/j.geobios.2024.11.008
Dimila Mothé , Angela Kinoshita , Oswaldo Baffa , Carlos A. Luna
{"title":"Doing the time warp again: Electron Spin Resonance dating reveals oldest numeric age for Notiomastodon platensis Ameghino, 1888 (Mammalia, Proboscidea)","authors":"Dimila Mothé , Angela Kinoshita , Oswaldo Baffa , Carlos A. Luna","doi":"10.1016/j.geobios.2024.11.008","DOIUrl":"10.1016/j.geobios.2024.11.008","url":null,"abstract":"<div><div>Here we used Electron Spin Resonance (ESR) dating methods on seven fossil specimens to update the temporal and geographic distributions of the Quaternary proboscidean <em>Notiomastodon platensis</em> Ameghino 1888, from Córdoba Province, Argentina. While abundant in the Late Pleistocene/Early Holocene South American fossil record, the knowledge about the Early-Middle Pleistocene records of this proboscidean is scarce due to limited numeric datings data. ESR results reveal numeric ages ranging from 560 ± 40 to 47 ± 7 ka, placing the species within the Ensenadan to Lujanian stages of the Pleistocene (Chibanian to Late Pleistocene). The Ensenadan record represents the oldest numeric age of <em>Notiomastodon platensis</em> in South America. The study highlights the importance of numeric dating in addressing the geochronological data gap for South American megafauna and reveals the multiple environments that <em>Notiomastodon platensis</em> inhabited during Quaternary, suggesting slow vertical migrations in response to climatic changes, with mountainous regions of Cordoba province serving as refuges. The need for further numeric datings is emphasized in this study, to improve our understanding of the evolutionary history and extinction drivers of South American proboscideans during the Quaternary.</div></div>","PeriodicalId":55116,"journal":{"name":"Geobios","volume":"91 ","pages":"Pages 81-88"},"PeriodicalIF":1.6,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144314653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
GeobiosPub Date : 2025-05-22DOI: 10.1016/j.geobios.2024.11.010
Pedro Correia , Artur A. Sá , Zélia Pereira
{"title":"Megaglomerospora lealiae nov. gen., nov. sp. from the upper Carboniferous of Portugal: the largest glomeromycotan fungal spores","authors":"Pedro Correia , Artur A. Sá , Zélia Pereira","doi":"10.1016/j.geobios.2024.11.010","DOIUrl":"10.1016/j.geobios.2024.11.010","url":null,"abstract":"<div><div>A new genus and species of fossil fungus, <em>Megaglomerospora lealiae</em>, is described from the Buçaco Carboniferous Basin (upper Stephanian C, Upper Pennsylvanian, upper Carboniferous), in central western Portugal. The new fossil fungus consists of a dense cluster of silicified large spores. These new fungal spores are oblong, subelliptical to subspherical-shaped, with a glabrous surface characterized by having a lipid-filled lumen, and display a strong septate-like hypha attached. The presence of lobe-shaped germination shields suggests close affinities to Diversisporales (Glomeromycota). <em>Megaglomerospora lealiae</em> nov. gen., nov. sp. is remarkably distinctive because it is by far the largest fossil fungal spore (∼1.6 mm long) documented for the phylum Glomeromycota. This is the first report of an endomycorrhizal‐like fungus from the Carboniferous of Iberia.</div></div>","PeriodicalId":55116,"journal":{"name":"Geobios","volume":"91 ","pages":"Pages 1-9"},"PeriodicalIF":1.6,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144154793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
GeobiosPub Date : 2025-05-22DOI: 10.1016/j.geobios.2024.11.009
Karl Krainer , Spencer G. Lucas , Daniel Vachard
{"title":"Mississippian-Lower Pennsylvanian foraminifers from the Sierra Nacimiento and San Pedro Mountains, North-Central New Mexico, USA","authors":"Karl Krainer , Spencer G. Lucas , Daniel Vachard","doi":"10.1016/j.geobios.2024.11.009","DOIUrl":"10.1016/j.geobios.2024.11.009","url":null,"abstract":"<div><div>In the Sierra Nacimiento-San Pedro Mountains-Jemez Mountains of north-central New Mexico (USA), the thin succession of Mississippian sediments is termed the Arroyo Peñasco Formation, overlain by the Log Springs Formation. The Arroyo Peñasco Formation is subdivided into Del Padre Member composed of siliciclastic sediments and the overlying Espiritu Santo Member composed of carbonate sediments. Foraminifers of the Espiritu Santo Member at Lion Spring in the northern San Pedro Mountains indicate a Tournaisian age. The lower Tournaisian (= Hastarian = biozones MFZ1-4 of <span><span>Poty et al., 2006</span></span> [Geological Magazine 143, 829–857]) is locally characterized by <em>Septaglomospiranella</em> ex gr. <em>primaeva</em>, <em>Septabrunsiina minuta</em> and <em>Tournayella</em> sp. The upper Tournaisian (= Ivorian = biozones MFZ5-9 of <span><span>Poty et al., 2006</span></span>) is characterized by <em>Spinoendothyra</em>, <em>Inflatoendothyra</em> and <em>Tuberendothyra</em>. In the Sierra Nacimiento-San Pedro Mountains-Jemez Mountains, the sediments of the Arroyo Peñasco Group are unconformably overlain by nonmarine redbeds of the Log Springs Formation (Serpukhovian/upper Chesterian). Some of the carbonate clasts of the basal conglomerate of the Log Springs Formation at Lion Spring contain late early Viséan (biozone MFZ11B of <span><span>Poty et al., 2006</span></span>) foraminifers and algae, including <em>Koninckopora</em> and <em>Paraarchaediscus</em>. These carbonate clasts are reworked from the underlying Arroyo Peñasco Formation (Espiritu Santo Member). In north-central New Mexico, a transgression during the Early Pennsylvanian (Morrowan) caused deposition of the shallow marine sediments of the Osha Canyon Formation. The Morrowan age of the Osha Canyon Formation is based on <em>Nigrispiroides</em> nov. gen., <em>Iriclinella</em>, <em>Globivalvulina</em>, and <em>Millerella</em>.</div></div>","PeriodicalId":55116,"journal":{"name":"Geobios","volume":"91 ","pages":"Pages 43-60"},"PeriodicalIF":1.6,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144314651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
GeobiosPub Date : 2025-03-26DOI: 10.1016/j.geobios.2024.11.007
Jesús Marugán-Lobón , Sergio M. Nebreda
{"title":"Craniocervical morphological integration in birds","authors":"Jesús Marugán-Lobón , Sergio M. Nebreda","doi":"10.1016/j.geobios.2024.11.007","DOIUrl":"10.1016/j.geobios.2024.11.007","url":null,"abstract":"<div><div>This study investigates the morphological diversity of the neck and its integration with skull anatomy in crown-group birds (Neornithes). The craniocervical articulation, where the skull connects with the neck, can adopt either caudal (rearward) or ventral (downward) orientations. Morphological coherence is crucial for maintaining head stability and precise movement, suggesting that the evolution of these structures must be not only functionally, but also developmentally coordinated (i.e., morphologically integrated). To explore this hypothesis, the relationship between conventional morphometric data of the neck and geometric morphometric data of the skull were assessed using multivariate statistics (Regressions and Two-block Partial Least Squares) across a broad phylogenetic range of Neornithes. Results indicate a significant level of integration between neck and skull morphologies, where variation in neck length, vertebral counts and relative lengths correspond predictably with specific craniocervical articulations. The most pronounced skull variation occurs around the occipital region, which we interpret as possibly relating to the mesodermic origin and shared genetic signalling in the morphogenesis of all craniocervical bones. Additionally, craniofacial changes align with craniocervical modifications, implying that the skull and neck evolve as a unified yet modular system. Analysis of selected fossils (<em>Tsaagan</em>, <em>Archaeopteryx</em>, and <em>Pengornis</em>) suggests that the ancestral craniocervical configuration was caudal, with neck changes associated with the development of a beak and craniocervical ventralization emerging in the lineage leading to modern birds.</div></div>","PeriodicalId":55116,"journal":{"name":"Geobios","volume":"90 ","pages":"Pages 77-85"},"PeriodicalIF":1.6,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143928088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
GeobiosPub Date : 2025-03-25DOI: 10.1016/j.geobios.2025.03.001
Francisco J. Serrano , Luis M. Chiappe , Ursula B. Göhlich
{"title":"Foreword for the Proceedings of the 10th International Meeting of the Society of Avian Paleontology and Evolution","authors":"Francisco J. Serrano , Luis M. Chiappe , Ursula B. Göhlich","doi":"10.1016/j.geobios.2025.03.001","DOIUrl":"10.1016/j.geobios.2025.03.001","url":null,"abstract":"","PeriodicalId":55116,"journal":{"name":"Geobios","volume":"90 ","pages":"Pages 1-4"},"PeriodicalIF":1.6,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143927437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}