Pub Date : 2025-08-05DOI: 10.1016/j.palwor.2025.201002
Ainul H. Ansari , Rajan Shukla , Avneet Kumar , Abu Talib
This study reports the Middle to Late Jurassic (Bajocian–Oxfordian) benthic foraminiferal assemblages from Kachchh, India, and assesses their significance as palaeoenvironmental proxies. Four distinct assemblages are identified to evaluate marine benthic foraminiferal groups along the inner-to-outer shelf gradient. From Bajocian to Oxfordian, four environmental fluctuation events were recognised. These fluctuations were examined in relation to bathymetry, organic matter (food availability), oxic and anoxic conditions, and species diversity. Except for the lower Callovian assemblages, the others exhibit favourable environments, ranging from moderately mesotrophic to eutrophic, middle to outer neritic (100–150 m), well-oxygenated conditions and specific diversities. The fluctuations may be due to the increased food influx (Bajocian–Callovian) and decreased dissolved oxygen in the bottom water (Callovian–Oxfordian). Fluctuations in dissolved oxygen and supply of organic matter were the primary environmental factors influencing the distribution pattern of benthic foraminiferal species in the Kachchh Basin. In shallow marine environments with well-oxygenated bottom waters, food availability and oxygen levels played a more decisive role in shaping assemblage structure than bathymetry. However, water depth exerted a greater influence on species distribution in deeper settings.
{"title":"Benthic foraminiferal assemblages from the Middle to Upper Jurassic rocks of the Kachchh Basin, India: Insights into taxonomy and palaeoenvironmental reconstruction","authors":"Ainul H. Ansari , Rajan Shukla , Avneet Kumar , Abu Talib","doi":"10.1016/j.palwor.2025.201002","DOIUrl":"10.1016/j.palwor.2025.201002","url":null,"abstract":"<div><div>This study reports the Middle to Late Jurassic (Bajocian–Oxfordian) benthic foraminiferal assemblages from Kachchh, India, and assesses their significance as palaeoenvironmental proxies. Four distinct assemblages are identified to evaluate marine benthic foraminiferal groups along the inner-to-outer shelf gradient. From Bajocian to Oxfordian, four environmental fluctuation events were recognised. These fluctuations were examined in relation to bathymetry, organic matter (food availability), oxic and anoxic conditions, and species diversity. Except for the lower Callovian assemblages, the others exhibit favourable environments, ranging from moderately mesotrophic to eutrophic, middle to outer neritic (100–150 m), well-oxygenated conditions and specific diversities. The fluctuations may be due to the increased food influx (Bajocian–Callovian) and decreased dissolved oxygen in the bottom water (Callovian–Oxfordian). Fluctuations in dissolved oxygen and supply of organic matter were the primary environmental factors influencing the distribution pattern of benthic foraminiferal species in the Kachchh Basin. In shallow marine environments with well-oxygenated bottom waters, food availability and oxygen levels played a more decisive role in shaping assemblage structure than bathymetry. However, water depth exerted a greater influence on species distribution in deeper settings.</div></div>","PeriodicalId":48708,"journal":{"name":"Palaeoworld","volume":"35 1","pages":"Article 201002"},"PeriodicalIF":1.7,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145929164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-08-05DOI: 10.1016/j.palwor.2025.201003
Michael S. Engel
An enigmatic new family of minute (less than 1 mm in length) proctotrupomorphan wasps is described and figured from Lower Cretaceous Lebanese amber. Uroprionulidae n. fam. is established for the new genus and species, Uroprionulus zenobia n. gen. n. sp. from the Bcharreh District of Lebanon. The fossil is a female with an elongate ovipositor and sheaths and with wings superficially resembling those of several extinct families of minute Proctotrupomorpha, such as Alavarommatidae, Archaeoserphitidae, and Spathiopterygidae. The characters of the family are considered in the context of those for other lineages of Proctotrupomorpha and a tentative revised classification is outlined.
从下白垩纪黎巴嫩琥珀中描述和描绘了一种神秘的新小黄蜂（长度小于1毫米）。尿毒杆菌科；为来自黎巴嫩Bcharreh地区的新属和新种Uroprionulus zenobia n. gen. n. sp.建立。该化石为雌性，具有细长的产卵器和鞘，其翅膀表面类似于几个已灭绝的微小直翅虫科，如alavaromatidae， Archaeoserphitidae和Spathiopterygidae。这个家族的特征是在其他直系的背景下考虑的，并概述了一个暂定的修订分类。
{"title":"A new family of proctotrupomorphan wasps in Lower Cretaceous amber of Lebanon (Hymenoptera)","authors":"Michael S. Engel","doi":"10.1016/j.palwor.2025.201003","DOIUrl":"10.1016/j.palwor.2025.201003","url":null,"abstract":"<div><div>An enigmatic new family of minute (less than 1 mm in length) proctotrupomorphan wasps is described and figured from Lower Cretaceous Lebanese amber. Uroprionulidae n. fam. is established for the new genus and species, <em>Uroprionulus zenobia</em> n. gen. n. sp. from the Bcharreh District of Lebanon. The fossil is a female with an elongate ovipositor and sheaths and with wings superficially resembling those of several extinct families of minute Proctotrupomorpha, such as Alavarommatidae, Archaeoserphitidae, and Spathiopterygidae. The characters of the family are considered in the context of those for other lineages of Proctotrupomorpha and a tentative revised classification is outlined.</div></div>","PeriodicalId":48708,"journal":{"name":"Palaeoworld","volume":"34 6","pages":"Article 201003"},"PeriodicalIF":1.7,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145418043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-07-31DOI: 10.1016/j.palwor.2025.201001
Nikita Bragin, Liubov Bragina
A well-preserved radiolarian assemblage was studied from the Upper Jurassic of the Domodedovo quarry, Moscow Region, Central Russia. Radiolarians were found within the Ermolino Formation (upper Oxfordian to lower Kimmeridgian), in phosphatic concretions. The radiolarian assemblage is represented by 29 species of 13 genera and has a boreal affinity with some southern influence indicated by the presence of Pantanellium. The assemblage is characterized by the abundance of Praeconocaryomma, common presence of Praeparvicingula, and rare presence of Phantum, Acanthocircus, Pantanellium and Nordvikella. Four new species are described: Acastea laevispina n. sp., Praeconocaryomma blomei n. sp., Phantum robustum n. sp., Nordvikella simplex n. sp.
对俄罗斯中部莫斯科州多莫杰多沃采石场上侏罗世保存完好的放射虫组合进行了研究。放射虫在Ermolino组（上牛津纪至下基默里吉纪）中被发现，在磷酸盐结合体中。放射虫组合由13属29种代表，具有北方亲缘关系，并有一些南方的影响，这是由Pantanellium的存在表明的。该组合的特点是丰富的praeconcaromma，常见的Praeparvicingula，罕见的Phantum， Acanthocircus， panantellium和Nordvikella。本文报道了4个新种：Acastea laevispina n. sp, preeconcaromma blomei n. sp, Phantum robustum n. sp, Nordvikella simplex n. sp。
{"title":"Radiolarians from the upper Oxfordian to lower Kimmeridgian (Upper Jurassic) Domodedovo Section, Moscow Region, Central Russia","authors":"Nikita Bragin, Liubov Bragina","doi":"10.1016/j.palwor.2025.201001","DOIUrl":"10.1016/j.palwor.2025.201001","url":null,"abstract":"<div><div>A well-preserved radiolarian assemblage was studied from the Upper Jurassic of the Domodedovo quarry, Moscow Region, Central Russia. Radiolarians were found within the Ermolino Formation (upper Oxfordian to lower Kimmeridgian), in phosphatic concretions. The radiolarian assemblage is represented by 29 species of 13 genera and has a boreal affinity with some southern influence indicated by the presence of <em>Pantanellium</em>. The assemblage is characterized by the abundance of <em>Praeconocaryomma</em>, common presence of <em>Praeparvicingula</em>, and rare presence of <em>Phantum</em>, <em>Acanthocircus</em>, <em>Pantanellium</em> and <em>Nordvikella</em>. Four new species are described: <em>Acastea laevispina</em> n. sp., <em>Praeconocaryomma blomei</em> n. sp., <em>Phantum robustum</em> n. sp., <em>Nordvikella simplex</em> n. sp.</div></div>","PeriodicalId":48708,"journal":{"name":"Palaeoworld","volume":"35 1","pages":"Article 201001"},"PeriodicalIF":1.7,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145929163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-07-31DOI: 10.1016/j.palwor.2025.200998
Lu-Da Xing , Xiao-Bing Wang , Martin Pickford , Yan-Jie Chen , Jiao Ma , Shu-Qiong Wang , Yi-Yang Liu , Shi-Qi Wang
Pliohyracidae, a group of large-bodied hyracoids, successfully colonised Eurasia during the late Cenozoic. However, their cranial morphology has remained poorly understood due to the scarcity of complete specimens in East Asia, particularly for Postschizotherium. This study presents the first nearly complete cranium of Postschizotherium cf. intermedium from the Early Pleistocene Longdan locality in Gansu Province, China. The cranium exhibits several distinctive features, including an exceptionally laterally projecting orbit, a massive maxillary sinus that significantly invades the orbital fossa, and a highly developed pre-orbital fossa system. These morphological traits, especially the first one, suggest that Postschizotherium is closely related to Pliohyrax and Kvabebihyrax, both being large pliohyracids from the upper Cenozoic of East Europe and West Asia. The morphology also suggests that Postschizotherium likely occupied semi-aquatic habitats, similar to those of extant hippos, with a diet primarily consisting of grasses. The discovery of this species at Longdan also provides evidence for a relatively humid palaeoenvironment in the region during the earliest Pleistocene, contributing to our understanding of the palaeoenvironmental conditions and evolutionary history of pliohyracids in Eurasia.
{"title":"The first cranium of Postschizotherium (Pliohyracidae, Hyracoidea) from the Lower Pleistocene of China","authors":"Lu-Da Xing , Xiao-Bing Wang , Martin Pickford , Yan-Jie Chen , Jiao Ma , Shu-Qiong Wang , Yi-Yang Liu , Shi-Qi Wang","doi":"10.1016/j.palwor.2025.200998","DOIUrl":"10.1016/j.palwor.2025.200998","url":null,"abstract":"<div><div>Pliohyracidae, a group of large-bodied hyracoids, successfully colonised Eurasia during the late Cenozoic. However, their cranial morphology has remained poorly understood due to the scarcity of complete specimens in East Asia, particularly for <em>Postschizotherium</em>. This study presents the first nearly complete cranium of <em>Postschizotherium</em> cf. <em>intermedium</em> from the Early Pleistocene Longdan locality in Gansu Province, China. The cranium exhibits several distinctive features, including an exceptionally laterally projecting orbit, a massive maxillary sinus that significantly invades the orbital fossa, and a highly developed pre-orbital fossa system. These morphological traits, especially the first one, suggest that <em>Postschizotherium</em> is closely related to <em>Pliohyrax</em> and <em>Kvabebihyrax</em>, both being large pliohyracids from the upper Cenozoic of East Europe and West Asia. The morphology also suggests that <em>Postschizotherium</em> likely occupied semi-aquatic habitats, similar to those of extant hippos, with a diet primarily consisting of grasses. The discovery of this species at Longdan also provides evidence for a relatively humid palaeoenvironment in the region during the earliest Pleistocene, contributing to our understanding of the palaeoenvironmental conditions and evolutionary history of pliohyracids in Eurasia.</div></div>","PeriodicalId":48708,"journal":{"name":"Palaeoworld","volume":"35 1","pages":"Article 200998"},"PeriodicalIF":1.7,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145929005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-07-29DOI: 10.1016/j.palwor.2025.201000
Kui Yan , Long-Long Shan , Jun Li , Thomas Servais
The investigation of acritarch and prasinophyte assemblages from the Tangchih Formation of Lower Ordovician outcrops from the eastern Yunnan Province reveals the presence of 39 genera and 54 species. The assemblages are dominated by the genera Coryphidium, Dactylofusa, Leiosphaeridia, Lophosphaeridium, Micrhystridium, Polygonium, Rhopaliophora, and the galeate acritarch plexus. The first occurrences of Aryballomorpha, Aureotesta clathrata simplex, Barakella, Coryphidium, C. bohemicum, Dactylofusa velifera, Dasydorus, Peteinosphaeridium, Rhopaliophora, Striatotheca and Vulcanisphaera indicate that the age of the Tangchih Formation corresponds to the latest Tremadocian to Floian. The microflora can be correlated to the messaoudensis-trifidum assemblage of western Europe and coeval assemblages worldwide. In terms of palaeoecology, the composition of the palynomorph assemblage, together with sedimentological and trace fossil evidence, indicates a shallow-water environment in the study area during the late Tremadocian to early Floian. In the context of palaeobiogeography, the palynomorph assemblage contains elements of both the ‘warm water’ Aryballomorpha-Athabascaella-Lua assemblage and the ‘cold water’ diacromorph acritarchs, possibly showing a mixed microflora in South China during the Early Ordovician.
{"title":"Early Ordovician acritarch and prasinophyte assemblages from eastern Yunnan, South China: Biostratigraphical and palaeobiogeographical implications","authors":"Kui Yan , Long-Long Shan , Jun Li , Thomas Servais","doi":"10.1016/j.palwor.2025.201000","DOIUrl":"10.1016/j.palwor.2025.201000","url":null,"abstract":"<div><div>The investigation of acritarch and prasinophyte assemblages from the Tangchih Formation of Lower Ordovician outcrops from the eastern Yunnan Province reveals the presence of 39 genera and 54 species. The assemblages are dominated by the genera <em>Coryphidium</em>, <em>Dactylofusa</em>, <em>Leiosphaeridia</em>, <em>Lophosphaeridium</em>, <em>Micrhystridium</em>, <em>Polygonium</em>, <em>Rhopaliophora</em>, and the galeate acritarch plexus. The first occurrences of <em>Aryballomorpha</em>, <em>Aureotesta clathrata simplex</em>, <em>Barakella</em>, <em>Coryphidium</em>, <em>C</em>. <em>bohemicum</em>, <em>Dactylofusa velifera</em>, <em>Dasydorus</em>, <em>Peteinosphaeridium</em>, <em>Rhopaliophora</em>, <em>Striatotheca</em> and <em>Vulcanisphaera</em> indicate that the age of the Tangchih Formation corresponds to the latest Tremadocian to Floian. The microflora can be correlated to the <em>messaoudensis-trifidum</em> assemblage of western Europe and coeval assemblages worldwide. In terms of palaeoecology, the composition of the palynomorph assemblage, together with sedimentological and trace fossil evidence, indicates a shallow-water environment in the study area during the late Tremadocian to early Floian. In the context of palaeobiogeography, the palynomorph assemblage contains elements of both the ‘warm water’ <em>Aryballomorpha</em>-<em>Athabascaella</em>-<em>Lua</em> assemblage and the ‘cold water’ diacromorph acritarchs, possibly showing a mixed microflora in South China during the Early Ordovician.</div></div>","PeriodicalId":48708,"journal":{"name":"Palaeoworld","volume":"35 1","pages":"Article 201000"},"PeriodicalIF":1.7,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145929107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-07-28DOI: 10.1016/j.palwor.2025.200999
Shahin Abd-Elhameed
The present study conducts foraminiferal analyses to evaluate the palaeoenvironmental conditions (e.g., palaeobathymetry, palaeooxygenation, and palaeoproductivity) of the upper Campanian–Maastrichtian Sudr Formation at Wadi Askhar El-Bahari, Northern Galala Plateau, Northern Eastern Desert, Egypt. Since the Sudr Formation received no attention concerning the foraminiferal content, a planktonic foraminiferal biostratigraphic framework was constructed, revealing nine (from Globotruncanella havanensis to Plummerita hantkeninoides) biozones. Furthermore, various quantitative and multivariate analyses of the recorded benthic foraminifera were performed to infer the variations in the palaeobathymetry, palaeooxygenation, and palaeoproductivity during the late Campanian–Maastrichtian. Seven benthic foraminiferal clusters were identified through statistical grouping analysis, revealing various distinct assemblages that differ in biotic traits (e.g., life-habit and diversity) and abiotic traits (e.g., oxygen availability and nutrient availability). A multidimensional plotting method (i.e., Non-metric Multidimensional Scaling) of the studied samples revealed eight main biofacies (I–VIII), each with a characteristic faunal composition. The vertical distribution of these biofacies reflects fluctuations in palaeo-water depth, oxygen, and nutrient availability. The lowermost part of the Sudr Formation is characterized by biofacies I, II, and III, indicating well-oxygenated, oligotrophic, outer neritic to upper bathyal environments. This is followed upward by intervals with biofacies II, IV, and V, reflecting oligo- to mesotrophic, upper bathyal environment, with well-oxygenated conditions. The upper half of the Sudr Formation comprises alternating intervals with biofacies IV, V, VII, representing well-oxygenated, mesotrophic, upper bathyal environment, and intervals with biofacies VI and VIII, characterizing poor-oxygenated, eutrophic, outer neritic to upper bathyal environments.
{"title":"Late Campanian–Maastrichtian foraminifera from Sudr Formation, Northern Galala Plateau, Egypt: Implications for biostratigraphy, palaeobathymetry, palaeooxygenation, and palaeoproductivity","authors":"Shahin Abd-Elhameed","doi":"10.1016/j.palwor.2025.200999","DOIUrl":"10.1016/j.palwor.2025.200999","url":null,"abstract":"<div><div>The present study conducts foraminiferal analyses to evaluate the palaeoenvironmental conditions (e.g., palaeobathymetry, palaeooxygenation, and palaeoproductivity) of the upper Campanian–Maastrichtian Sudr Formation at Wadi Askhar El-Bahari, Northern Galala Plateau, Northern Eastern Desert, Egypt. Since the Sudr Formation received no attention concerning the foraminiferal content, a planktonic foraminiferal biostratigraphic framework was constructed, revealing nine (from <em>Globotruncanella havanensis</em> to <em>Plummerita hantkeninoides</em>) biozones. Furthermore, various quantitative and multivariate analyses of the recorded benthic foraminifera were performed to infer the variations in the palaeobathymetry, palaeooxygenation, and palaeoproductivity during the late Campanian–Maastrichtian. Seven benthic foraminiferal clusters were identified through statistical grouping analysis, revealing various distinct assemblages that differ in biotic traits (e.g., life-habit and diversity) and abiotic traits (e.g., oxygen availability and nutrient availability). A multidimensional plotting method (i.e., Non-metric Multidimensional Scaling) of the studied samples revealed eight main biofacies (I–VIII), each with a characteristic faunal composition. The vertical distribution of these biofacies reflects fluctuations in palaeo-water depth, oxygen, and nutrient availability. The lowermost part of the Sudr Formation is characterized by biofacies I, II, and III, indicating well-oxygenated, oligotrophic, outer neritic to upper bathyal environments. This is followed upward by intervals with biofacies II, IV, and V, reflecting oligo- to mesotrophic, upper bathyal environment, with well-oxygenated conditions. The upper half of the Sudr Formation comprises alternating intervals with biofacies IV, V, VII, representing well-oxygenated, mesotrophic, upper bathyal environment, and intervals with biofacies VI and VIII, characterizing poor-oxygenated, eutrophic, outer neritic to upper bathyal environments.</div></div>","PeriodicalId":48708,"journal":{"name":"Palaeoworld","volume":"35 1","pages":"Article 200999"},"PeriodicalIF":1.7,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145929168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-07-22DOI: 10.1016/j.palwor.2025.200996
Ding-Ge Guo , Sayyed Ghyour Abbas , Qi-Gao Jiangzuo , Chun-Xiao Li , Yan-Wu Yang , Jia-Yong Cao , Bin Zou , Shi-Qi Wang , Xue-Ping Ji
As a small-sized Bovini, Pachyportax, originated in the Late Miocene Siwaliks and subsequently dispersed to neighbouring regions in Southeast Asia and the Arabian Peninsula, and eventually reached Yunnan, China. However, no fossil material of this genus had been discovered in China prior to this study. Here we report a new species Pachyportax zhaotongensis n. sp., from an important fossil ape locality, the Shuitangba site in Zhaotong, Yunnan, China, dated at approximately 6.2 Ma. The new species displays the diagnostic characteristics of Pachyportax, such as a robust horn core that extends laterally and backward, with a slightly convex medial side and a flatter lateral side, featuring anterior and posterior keels; the cheek teeth are hypsodont, with moderately developed ribs, folds and basal pillars. It also shows some differences from the known species: the horn core insertion is distant from the orbit and shows no significant torsion, and the anterior and posterior keels on the horn core are less pronounced. These advanced characteristics indicated that Pachyportax zhaotongensis n. sp. represents a late evolutionary stage of Pachyportax. This is also the first report of Pachyportax in China. In addition, based on a phylogenetic analysis, we clarify the relationship of Selenoportax and Pachyportax, and briefly explore the evolution and geographical distribution of the two genera.
Pachyportax是一种小型的Bovini，起源于晚中新世的siwalik，随后分散到东南亚和阿拉伯半岛的邻近地区，最终到达中国云南。然而，在此研究之前，在中国尚未发现该属的化石材料。本文报道了一新种Pachyportax zhaotongensis n. sp，来自中国云南昭通水塘坝类人猿化石重要产地，其年代约为6.2 Ma。该新种表现出Pachyportax的诊断特征，如强健的角核向外侧和向后延伸，内侧略凸，外侧较平，具有前后龙骨；颊齿是下齿，有中等发育的肋骨、褶皱和基柱。它也显示出与已知物种的一些差异：角核插入距离轨道较远，没有明显的扭转，角核上的前后龙骨不太明显。这些先进的特征表明，Pachyportax zhaotongensis n. sp代表了Pachyportax的晚期进化阶段。这也是国内首次报道Pachyportax。此外，在系统发育分析的基础上，明确了Selenoportax和Pachyportax的关系，并简要探讨了这两个属的进化和地理分布。
{"title":"New Pachyportax fossils from the Late Miocene Shuitangba locality, Yunnan, revealing the early Bovini evolution and radiation","authors":"Ding-Ge Guo , Sayyed Ghyour Abbas , Qi-Gao Jiangzuo , Chun-Xiao Li , Yan-Wu Yang , Jia-Yong Cao , Bin Zou , Shi-Qi Wang , Xue-Ping Ji","doi":"10.1016/j.palwor.2025.200996","DOIUrl":"10.1016/j.palwor.2025.200996","url":null,"abstract":"<div><div>As a small-sized Bovini, <em>Pachyportax</em>, originated in the Late Miocene Siwaliks and subsequently dispersed to neighbouring regions in Southeast Asia and the Arabian Peninsula, and eventually reached Yunnan, China. However, no fossil material of this genus had been discovered in China prior to this study. Here we report a new species <em>Pachyportax zhaotongensis</em> n. sp., from an important fossil ape locality, the Shuitangba site in Zhaotong, Yunnan, China, dated at approximately 6.2 Ma. The new species displays the diagnostic characteristics of <em>Pachyportax</em>, such as a robust horn core that extends laterally and backward, with a slightly convex medial side and a flatter lateral side, featuring anterior and posterior keels; the cheek teeth are hypsodont, with moderately developed ribs, folds and basal pillars. It also shows some differences from the known species: the horn core insertion is distant from the orbit and shows no significant torsion, and the anterior and posterior keels on the horn core are less pronounced. These advanced characteristics indicated that <em>Pachyportax zhaotongensis</em> n. sp. represents a late evolutionary stage of <em>Pachyportax</em>. This is also the first report of <em>Pachyportax</em> in China. In addition, based on a phylogenetic analysis, we clarify the relationship of <em>Selenoportax</em> and <em>Pachyportax</em>, and briefly explore the evolution and geographical distribution of the two genera.</div></div>","PeriodicalId":48708,"journal":{"name":"Palaeoworld","volume":"35 1","pages":"Article 200996"},"PeriodicalIF":1.7,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145929003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study reports the Teredolites clavatus borings within the Early Cretaceous Lebanese amber from the Hammana-Mdeirij outcrop, offering new insights into the taphonomy of a fossil resin. These findings represent one of the oldest known examples of this ichnospecies in fossil resins and are similar in age to borings known from the Jordanian amber. The club-shaped borings produced by marine wood-boring bivalves (most probably piddocks) are interpreted as domichnia belonging to the Teredolites ichnofacies. Four amber pebbles containing well-preserved borings were examined, one of which retains a distinct bioglyph on its interior surface. The impact of interpretation fossil resins as a xylic or lithic substrate is presented, in ichnotaxonomical and paleoenvironmental contexts. The studied specimens support a taphonomic model in which bored amber fragments were reworked and deposited, together with xylite material, during a regressive phase along the Tethyan shoreline. The absence of Apectoichnus and other woodground borings corroborates this interpretation. This study demonstrates the feasibility of using trace fossils in amber for reconstructing depositional environments and enhances the ichnological and paleoecological framework of Lebanese amber-bearing sequences with new data.
{"title":"Teredolites clavatus borings in fossil resins and their significance — new data from Cretaceous Lebanese amber","authors":"Błażej Bojarski , Karolina Cierocka , Sahar Azar , Jacek Szwedo","doi":"10.1016/j.palwor.2025.200997","DOIUrl":"10.1016/j.palwor.2025.200997","url":null,"abstract":"<div><div>This study reports the <em>Teredolites clavatus</em> borings within the Early Cretaceous Lebanese amber from the Hammana-Mdeirij outcrop, offering new insights into the taphonomy of a fossil resin. These findings represent one of the oldest known examples of this ichnospecies in fossil resins and are similar in age to borings known from the Jordanian amber. The club-shaped borings produced by marine wood-boring bivalves (most probably piddocks) are interpreted as domichnia belonging to the Teredolites ichnofacies. Four amber pebbles containing well-preserved borings were examined, one of which retains a distinct bioglyph on its interior surface. The impact of interpretation fossil resins as a xylic or lithic substrate is presented, in ichnotaxonomical and paleoenvironmental contexts. The studied specimens support a taphonomic model in which bored amber fragments were reworked and deposited, together with xylite material, during a regressive phase along the Tethyan shoreline. The absence of <em>Apectoichnus</em> and other woodground borings corroborates this interpretation. This study demonstrates the feasibility of using trace fossils in amber for reconstructing depositional environments and enhances the ichnological and paleoecological framework of Lebanese amber-bearing sequences with new data.</div></div>","PeriodicalId":48708,"journal":{"name":"Palaeoworld","volume":"34 6","pages":"Article 200997"},"PeriodicalIF":1.7,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145418044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-07-18DOI: 10.1016/j.palwor.2025.200995
Lei Zhang , Ying Wu , Fan Zhai , Chen-Zhang Duan , Shan-Shan Fu , Shan Chang , Yan Ye , Can Chen , Xia Wang , Xian-Guo Lang , Qing-Lai Feng , Marie-Béatrice Forel
As phylogenetically basal metazoans, sponges (phylum Porifera) provide crucial insights into the origins of animal biomineralization and early body plan innovation. However, articulated sponge fossils remain exceptionally rare in Ediacaran–Cambrian transition strata, with most records limited to isolated spicules or ambiguous biomineralized structures. This study reports siliceous and phosphatically preserved sponge spicule tufts from the lower Yanjiahe Formation (∼535 Ma, Fortunian Stage) at the Muyangxi section (eastern Three Gorges area, South China). Dominated by monaxons, with co-occurring pentactine spicules, two morphotypes are distinguished: Type 1 tufts comprise slender, hollow monaxons (mean value of the maximum width: ∼15.9 µm, n = 37) with uniform near-parallel alignment, while Type 2 tufts consist of sturdier phosphatized monaxons (mean value of the maximum width: ∼91.1 µm, n = 135) arranged as subparallel bundles, slightly radially oriented arrangements, and sometimes semi-randomly in single layers, occasionally with perpendicular alignments to the adjacent layers. Small curved oxeas in the Type 2 tufts suggest incipient hierarchical organization. Although fragmentary preservation limits taxonomic resolution, these tufts likely represent the earliest unequivocal biomineralized sponges, potentially corresponding to stem-group Demospongiae and/or Hexactinellida (Silicea). In combination with the previous evidences found from the Ediacaran–Cambrian transition, we hypothesize that early sponge biomineralization was likely monaxon-dominated, with hexactines arising via axial fusion or increased axis number, culminating in hexactinellid diversification by Terreneuvian Stage 2. Integrated with Small Shelly Fossil Zone 1 biochronology, our findings indicate rapid pre-Fortunian to Fortunian-stage spicule enlargement (≤ 200 μm to ≥ 500 μm) and architectural complexification, aligning with early Cambrian ecological escalation. Alternatively, it is possible that the divergence between Hexactinellida and Demospongiae may predate biomineralization, as their last common ancestor may have lacked siliceous spicules. The Yanjiahe spicules illuminate a critical prelude to the Cambrian sponge explosion, bridging Ediacaran soft-bodied ancestors and later diverse, mineralized clades.
作为系统发育上的基础后生动物，海绵（门Porifera）为动物生物矿化和早期身体结构创新的起源提供了重要的见解。然而，在埃迪卡拉-寒武纪过渡地层中，关节海绵化石仍然非常罕见，大多数记录仅限于孤立的针状体或模糊的生物矿化结构。本文报道了三峡东部木羊溪剖面下延家河组（~ 535 Ma，福图尼期）的硅质和磷化保存的海绵针状簇。以单轴突为主，同时出现五行状针状体，可区分为两种形态：1型簇包括细长中空的单轴突（最大宽度平均值：~ 15.9µm, n = 37），具有均匀的近平行排列，而2型簇由更坚固的磷化单轴突组成(最大宽度平均值：~ 91.1µm, n = 135)排列成亚平行束，略呈放射状排列，有时半随机排列在单层中，偶尔与相邻层垂直排列。2型丛中的小弯曲的牛轭表明了等级组织的初步形成。尽管碎片的保存限制了分类学的分辨率，但这些簇可能代表了最早的明确的生物矿化海绵，可能对应于茎群Demospongiae和/或Hexactinellida （silea）。结合埃迪卡拉-寒武纪过渡时期的证据，我们推测早期海绵生物矿化可能以单轴生物为主，通过轴向融合或轴数增加产生六轴生物，最终在Terreneuvian第2阶段实现六轴生物多样化。结合小Shelly化石带1的生物年代学，研究结果表明，前福尔图尼期至福尔图尼期针状体迅速扩大（≤200 μm至≥500 μm），建筑复杂，与早寒武世的生态升级一致。另外，Hexactinellida和Demospongiae之间的分化可能早于生物矿化，因为它们最后的共同祖先可能缺乏硅质针状体。延家河针状体揭示了寒武纪海绵大爆发的一个重要前奏，连接了埃迪卡拉纪的软体祖先和后来多样化的矿化进化枝。
{"title":"The earliest sponge spicule tufts from the Cambrian Lower Yanjiahe Formation, Three Gorges area, South China","authors":"Lei Zhang , Ying Wu , Fan Zhai , Chen-Zhang Duan , Shan-Shan Fu , Shan Chang , Yan Ye , Can Chen , Xia Wang , Xian-Guo Lang , Qing-Lai Feng , Marie-Béatrice Forel","doi":"10.1016/j.palwor.2025.200995","DOIUrl":"10.1016/j.palwor.2025.200995","url":null,"abstract":"<div><div>As phylogenetically basal metazoans, sponges (phylum Porifera) provide crucial insights into the origins of animal biomineralization and early body plan innovation. However, articulated sponge fossils remain exceptionally rare in Ediacaran–Cambrian transition strata, with most records limited to isolated spicules or ambiguous biomineralized structures. This study reports siliceous and phosphatically preserved sponge spicule tufts from the lower Yanjiahe Formation (∼535 Ma, Fortunian Stage) at the Muyangxi section (eastern Three Gorges area, South China). Dominated by monaxons, with co-occurring pentactine spicules, two morphotypes are distinguished: Type 1 tufts comprise slender, hollow monaxons (mean value of the maximum width: ∼15.9 µm, n = 37) with uniform near-parallel alignment, while Type 2 tufts consist of sturdier phosphatized monaxons (mean value of the maximum width: ∼91.1 µm, n = 135) arranged as subparallel bundles, slightly radially oriented arrangements, and sometimes semi-randomly in single layers, occasionally with perpendicular alignments to the adjacent layers. Small curved oxeas in the Type 2 tufts suggest incipient hierarchical organization. Although fragmentary preservation limits taxonomic resolution, these tufts likely represent the earliest unequivocal biomineralized sponges, potentially corresponding to stem-group Demospongiae and/or Hexactinellida (Silicea). In combination with the previous evidences found from the Ediacaran–Cambrian transition, we hypothesize that early sponge biomineralization was likely monaxon-dominated, with hexactines arising via axial fusion or increased axis number, culminating in hexactinellid diversification by Terreneuvian Stage 2. Integrated with Small Shelly Fossil Zone 1 biochronology, our findings indicate rapid pre-Fortunian to Fortunian-stage spicule enlargement (≤ 200 μm to ≥ 500 μm) and architectural complexification, aligning with early Cambrian ecological escalation. Alternatively, it is possible that the divergence between Hexactinellida and Demospongiae may predate biomineralization, as their last common ancestor may have lacked siliceous spicules. The Yanjiahe spicules illuminate a critical prelude to the Cambrian sponge explosion, bridging Ediacaran soft-bodied ancestors and later diverse, mineralized clades.</div></div>","PeriodicalId":48708,"journal":{"name":"Palaeoworld","volume":"34 6","pages":"Article 200995"},"PeriodicalIF":1.7,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145418050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-07-18DOI: 10.1016/j.palwor.2025.200994
Matías J. Mango , Guillermo L. Albanesi
The present study deals with the conodont fauna and its biostratigraphy recorded in the upper 14 m of the San Juan Formation at the Potrerillos Creek section, northern Central Precordillera of Argentina. The analysis of seven conodont samples from levels of biostratigraphic interest allowed the identification of 10,676 conodont elements, assigned to 41 genera and 59 species. One new genus (Resinodus n. gen.) and two new species (Resinodus nalamamacatus n. gen. n. sp. and Tripodus precolaevis n. sp.) are defined, expanding the knowledge of conodont taxonomy for the Dapingian (Middle Ordovician) in Argentina. Recognition of Tripodus precolaevis n. sp., whose range is restricted to the early–middle Dapingian, supports the definition of the Tripodus precolaevis Zone in the upper San Juan Formation. This biozone potentially correlates with the Baltoniodus triangularis Zone in China and Baltica, and possibly also in northwestern Argentina. The Tripodus precolaevis Zone may correlate with the lower part of the Tripodus laevis Zone and the lower part of the Neomultioistodus compressus/Tricladiodus clypeus Zone in North America. The conodont elements from the Potrerillos Creek section have a CAI of 2.5–3, indicating burial paleotemperatures of 85 °C–200 °C. Most elements display overgrowths of silica crystals, while a few elements have recrystallized surface lamella. These fossilization features may be attributed to diagenetic effects due to intense tectonism in the Andean Orogeny.
本文研究了阿根廷中部Precordillera北部Potrerillos Creek剖面圣胡安组上部14 m处的牙形石动物群及其生物地层学记录。对来自生物地层兴趣水平的7个牙形石样本进行分析，鉴定出10,676个牙形石元素，归属于41属59种。确定了一个新属（Resinodus n. gen.）和两个新种（Resinodus nalamamacatus n. gen. sp.和Tripodus precolaevis n. sp.），扩大了阿根廷大坪期（中奥陶世）牙形刺分类的知识。发现范围局限于大坪纪早中期的三足前colaevis n. sp.，支持了圣胡安组上部三足前colaevis带的定义。该生物带可能与中国和波罗的海的Baltoniodus triangularis生物带有关，也可能与阿根廷西北部的Baltoniodus triangularis生物带有关。Tripodus precolaevis带可能与北美洲的Tripodus laevis带的下部和nemultiistodus compressus/Tricladiodus clypeus带的下部相对应。potrerilllos Creek剖面牙形石元素的CAI值为2.5 ~ 3，表明古埋藏温度为85℃~ 200℃。大多数元素显示出硅晶体的过度生长，而少数元素表面有再结晶的薄片。这些化石特征可能是由于安第斯造山运动强烈的构造作用造成的成岩作用。
{"title":"New conodont taxa and correlation of the upper San Juan Formation, Dapingian (Ordovician), at Potrerillos Creek, Argentine Precordillera","authors":"Matías J. Mango , Guillermo L. Albanesi","doi":"10.1016/j.palwor.2025.200994","DOIUrl":"10.1016/j.palwor.2025.200994","url":null,"abstract":"<div><div>The present study deals with the conodont fauna and its biostratigraphy recorded in the upper 14 m of the San Juan Formation at the Potrerillos Creek section, northern Central Precordillera of Argentina. The analysis of seven conodont samples from levels of biostratigraphic interest allowed the identification of 10,676 conodont elements, assigned to 41 genera and 59 species. One new genus (<em>Resinodus</em> n. gen.) and two new species (<em>Resinodus nalamamacatus</em> n. gen. n. sp. and <em>Tripodus precolaevis</em> n. sp.) are defined, expanding the knowledge of conodont taxonomy for the Dapingian (Middle Ordovician) in Argentina. Recognition of <em>Tripodus precolaevis</em> n. sp., whose range is restricted to the early–middle Dapingian, supports the definition of the <em>Tripodus precolaevis</em> Zone in the upper San Juan Formation. This biozone potentially correlates with the <em>Baltoniodus triangularis</em> Zone in China and Baltica, and possibly also in northwestern Argentina. The <em>Tripodus precolaevis</em> Zone may correlate with the lower part of the <em>Tripodus laevis</em> Zone and the lower part of the <em>Neomultioistodus compressus</em>/<em>Tricladiodus clypeus</em> Zone in North America. The conodont elements from the Potrerillos Creek section have a CAI of 2.5–3, indicating burial paleotemperatures of 85 °C–200 °C. Most elements display overgrowths of silica crystals, while a few elements have recrystallized surface lamella. These fossilization features may be attributed to diagenetic effects due to intense tectonism in the Andean Orogeny.</div></div>","PeriodicalId":48708,"journal":{"name":"Palaeoworld","volume":"34 6","pages":"Article 200994"},"PeriodicalIF":1.7,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145418046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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