A diverse and well-preserved radiolarian assemblage from the Malongulli Formation, New South Wales, Australia, contains 13 species representing 10 genera and six families. One new genus, Wiradjuri, is introduced to accommodate pre-Devonian single-shelled entactiniid taxa, and one new species, Secuicollacta malongulliensis, is recorded together with some previously described forms. The microstructures of the “rotasphaerid structure/primary unit” and the “ectopic spicule” are investigated to validate their roles as fundamental units in the Secuicollactidae, together with comprehensive documentation of the previously enigmatic Pseudorotasphaera internal skeleton. The results of this investigation suggest that, among all radiolarian genera that survived the Late Ordovician Mass Extinction event (LOME) and transitioned into the Silurian, Secuicollacta, Haplotaeniatum, and Palaeoephippium maintained stable body plans during the transition and were more successfully established. The selective advantages these lineages had during the LOME were most likely spontaneous outcomes of the mode of structural development involving sequential skeletogenesis and a tendency to evolve toward simpler body plans. UUID: http://zoobank.org/264c026f-35af-4025-a4f7-de8f9a91f8b9
{"title":"Micro-CT analysis of Katian radiolarians from the Malongulli Formation, New South Wales, Australia, and implications for skeletogenesis","authors":"","doi":"10.1017/jpa.2023.13","DOIUrl":"https://doi.org/10.1017/jpa.2023.13","url":null,"abstract":"\u0000 A diverse and well-preserved radiolarian assemblage from the Malongulli Formation, New South Wales, Australia, contains 13 species representing 10 genera and six families. One new genus, Wiradjuri, is introduced to accommodate pre-Devonian single-shelled entactiniid taxa, and one new species, Secuicollacta malongulliensis, is recorded together with some previously described forms. The microstructures of the “rotasphaerid structure/primary unit” and the “ectopic spicule” are investigated to validate their roles as fundamental units in the Secuicollactidae, together with comprehensive documentation of the previously enigmatic Pseudorotasphaera internal skeleton.\u0000 The results of this investigation suggest that, among all radiolarian genera that survived the Late Ordovician Mass Extinction event (LOME) and transitioned into the Silurian, Secuicollacta, Haplotaeniatum, and Palaeoephippium maintained stable body plans during the transition and were more successfully established. The selective advantages these lineages had during the LOME were most likely spontaneous outcomes of the mode of structural development involving sequential skeletogenesis and a tendency to evolve toward simpler body plans.\u0000 UUID: http://zoobank.org/264c026f-35af-4025-a4f7-de8f9a91f8b9","PeriodicalId":50098,"journal":{"name":"Journal of Paleontology","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48091671","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}
Evidence from the earliest-known crinoids (Tremadocian, Early Ordovician), called protocrinoids, is used to hypothesize initial steps by which elements of the calyx evolved. Protocrinoid calyces are composed of extraxial primary and surrounding secondary plates (both of which have epispires along their sutures) that are unlike those of more crownward fossil and extant crinoids in which equivalent calycinal plating is strongly organized. These reductions inspired several schemes by which to name the plates in these calyces. However, the primary-secondary systems seen in protocrinoids first appeared among Cambrian stem radial echinoderms, with primaries representing centers around which secondaries were sequentially added during ontogeny. Therefore, the protocrinoid calyx represents an intermediate condition between earliest echinoderms and crownward crinoids. Position and ontogeny indicate certain primaries remained as loss of secondaries occurred, resulting in abutting of primaries into the conjoined alternating circlets characteristic of crinoids. This transformative event included suppression of secondary plating and modification or, more commonly, elimination of respiratory structures. These data indicate subradial calyx plate terminology does not correspond with most common usage, but rather, supports an alternative redefinition of these traditional expressions. Extension and adoral growth of fixed rays during calyx ontogeny preceded conjoined primaries in earliest crinoids. Restriction with modification or elimination of calyx respiratory structures also accompanied this modification. Phylogenetic analyses strongly support crinoid origination from early pentaradiate echinoderms, separate from blastozoans. Accordingly, all Tremadocian crinoids express a distinctive aggregate of plesiomorphic and apomorphic commonalities; all branch early within the crinoid clade, separate from traditional subclass-level clades. Nevertheless, each taxon within this assemblage expresses at least one diagnostic apomorphy of camerate, cladid, or disparid clades.
{"title":"Crinoid calyx origin from stem radial echinoderms","authors":"T. Guensburg, R. Mooi, N. Mongiardino Koch","doi":"10.1017/jpa.2023.14","DOIUrl":"https://doi.org/10.1017/jpa.2023.14","url":null,"abstract":"\u0000 Evidence from the earliest-known crinoids (Tremadocian, Early Ordovician), called protocrinoids, is used to hypothesize initial steps by which elements of the calyx evolved. Protocrinoid calyces are composed of extraxial primary and surrounding secondary plates (both of which have epispires along their sutures) that are unlike those of more crownward fossil and extant crinoids in which equivalent calycinal plating is strongly organized. These reductions inspired several schemes by which to name the plates in these calyces. However, the primary-secondary systems seen in protocrinoids first appeared among Cambrian stem radial echinoderms, with primaries representing centers around which secondaries were sequentially added during ontogeny. Therefore, the protocrinoid calyx represents an intermediate condition between earliest echinoderms and crownward crinoids. Position and ontogeny indicate certain primaries remained as loss of secondaries occurred, resulting in abutting of primaries into the conjoined alternating circlets characteristic of crinoids. This transformative event included suppression of secondary plating and modification or, more commonly, elimination of respiratory structures. These data indicate subradial calyx plate terminology does not correspond with most common usage, but rather, supports an alternative redefinition of these traditional expressions. Extension and adoral growth of fixed rays during calyx ontogeny preceded conjoined primaries in earliest crinoids. Restriction with modification or elimination of calyx respiratory structures also accompanied this modification. Phylogenetic analyses strongly support crinoid origination from early pentaradiate echinoderms, separate from blastozoans. Accordingly, all Tremadocian crinoids express a distinctive aggregate of plesiomorphic and apomorphic commonalities; all branch early within the crinoid clade, separate from traditional subclass-level clades. Nevertheless, each taxon within this assemblage expresses at least one diagnostic apomorphy of camerate, cladid, or disparid clades.","PeriodicalId":50098,"journal":{"name":"Journal of Paleontology","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49040300","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}
{"title":"JPA volume 97 S92 Cover and Front matter","authors":"","doi":"10.1017/jpa.2023.16","DOIUrl":"https://doi.org/10.1017/jpa.2023.16","url":null,"abstract":"","PeriodicalId":50098,"journal":{"name":"Journal of Paleontology","volume":" ","pages":"f1 - f2"},"PeriodicalIF":1.4,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48809624","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}
Abstract. The Early Pennsylvanian Nagaiwa Formation contains fossils such as corals, fusulinids, and ostracodes, and its age and depositional environments have been determined by fusulinids and sedimentology. In this study, I describe the ostracode assemblages from the Nagaiwa Formation. Moreover, I provide a reconstruction of the paleogeography of northeastern Japan during the Early Pennsylvanian by comparing this ostracode assemblage with assemblages from other regions during the same period. Thirty ostracode species, including 12 genera, have been identified, most of which are endemic species and 10 of which are new: Jordanites michinokuensis n. sp., Thuringobolbina ikeyai n. sp., Aechmina iwatensis n. sp., Pseudobythocypris asiatica n. sp., P. zipangu n. sp., P. siveteri n. sp., Platyrhomboides tohokuensis n. sp., P. japonica n. sp., Healdia ofunatensis n. sp., and H. rikutyuensis n. sp. Two of these species are also found in central Japan. The ostracodes from the Nagaiwa Formation are unique when compared with any other similarly aged assemblages.
{"title":"Paleogeographical and paleoenvironmental significance of ostracodes from the Pennsylvanian Nagaiwa Formation, northeast Japan","authors":"G. Tanaka","doi":"10.1017/jpa.2022.108","DOIUrl":"https://doi.org/10.1017/jpa.2022.108","url":null,"abstract":"Abstract. The Early Pennsylvanian Nagaiwa Formation contains fossils such as corals, fusulinids, and ostracodes, and its age and depositional environments have been determined by fusulinids and sedimentology. In this study, I describe the ostracode assemblages from the Nagaiwa Formation. Moreover, I provide a reconstruction of the paleogeography of northeastern Japan during the Early Pennsylvanian by comparing this ostracode assemblage with assemblages from other regions during the same period. Thirty ostracode species, including 12 genera, have been identified, most of which are endemic species and 10 of which are new: Jordanites michinokuensis n. sp., Thuringobolbina ikeyai n. sp., Aechmina iwatensis n. sp., Pseudobythocypris asiatica n. sp., P. zipangu n. sp., P. siveteri n. sp., Platyrhomboides tohokuensis n. sp., P. japonica n. sp., Healdia ofunatensis n. sp., and H. rikutyuensis n. sp. Two of these species are also found in central Japan. The ostracodes from the Nagaiwa Formation are unique when compared with any other similarly aged assemblages.","PeriodicalId":50098,"journal":{"name":"Journal of Paleontology","volume":"97 1","pages":"1 - 33"},"PeriodicalIF":1.4,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46025592","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}
Abstract. This work provides the detailed investigation (taxonomy, biostratigraphy, and paleoecology) of a nonmarine ostracod fauna from the Shinekhudag Formation in Gobi–Altai area, southwest Mongolia. The samples from two sections (Tsagaan Tsuvarga and Oshih Hollow East) yielded various ostracods assigned to nine species belonging to six genera: Cypridea verrucata Neustrueva, 1974, C. ihsienensis Hou, 1958, C. unicostata Galeeva, 1955, C. tumefacta Neustrueva, 1974, Yumenia cf. Y. oriformis Hou, 1958, Scabriculocypris subscalara Zhang and Chen in Ye et al., 2003, ?Trapezoidella sp., Candona sp., and Vlakomia ulanense Neustrueva, 1977. The biostratigraphic application of our taxonomic results suggests that the age of the Shinekhudag Formation is Barremian–Aptian. In addition, the ostracod fauna shows strong affinities to faunas from northeast China and potentially northwest China, providing evidence of faunal exchanges between these regions and southwest Mongolia. The new discovery of Vlakomia ulanense indicates that mid-Cretaceous (Albian) species in northeast China probably originated in Mongolia at the time of deposition of the Shinekhudag Formation. Two ostracod assemblages in the studied sections reflect that different paleoenvironment settings have existed during deposition; the Tsagaan Tsuvarga Section represents a shallow-littoral zone of athalassic (inland) saline lake under arid climate, and the dominance of cypridoideans of the Oshih Hollow East Section is indicative of ephemeral water bodies.
摘要本工作对蒙古西南戈壁-阿尔泰地区Shinekhudag组的一个非海洋介形虫动物群进行了详细的调查（分类学、生物地层学和古生态学）。来自两个剖面（Tsagaan Tsuvarga和Oshih Hollow East）的样本产生了各种介形虫，分为六属九种：Cypridea verrucata Neustrueva，1974，C.ihsienensis Hou，1958，C.unicostata Galeeva，1955，C.tumefacta Neustruva，1974，Yumenia cf.Y.oriformis Hou，1956，Scabriculocypis subscalara Zhang和Chen in Ye et al.，2003？Trapezoidella sp.、Candona sp.和Vlakomia ulanense Neustrueva，1977年。我们的分类学结果的生物地层学应用表明，Shinekhudag组的年龄为Barremian-Aptian。此外，介形虫动物群与中国东北和可能的中国西北的动物群表现出强烈的亲缘关系，为这些地区与蒙古西南部之间的动物群交流提供了证据。新发现的乌兰藻表明，我国东北地区白垩纪中期（阿尔比阶）物种可能起源于Shinekhudag组沉积时的蒙古。研究剖面中的两个介形虫组合反映了沉积过程中存在不同的古环境背景；Tsagaan-Tsuvarga剖面代表了干旱气候下古典（内陆）盐湖的浅水沿岸带，而Oshih Hollow东段的塞浦路斯类占主导地位，表明存在短暂水体。
{"title":"Nonmarine ostracod fauna from the Lower Cretaceous Shinekhudag Formation (southwest Mongolia): taxonomy, biostratigraphy, and paleoecology","authors":"Byung-Do Choi, Yaqiong Wang","doi":"10.1017/jpa.2023.5","DOIUrl":"https://doi.org/10.1017/jpa.2023.5","url":null,"abstract":"Abstract. This work provides the detailed investigation (taxonomy, biostratigraphy, and paleoecology) of a nonmarine ostracod fauna from the Shinekhudag Formation in Gobi–Altai area, southwest Mongolia. The samples from two sections (Tsagaan Tsuvarga and Oshih Hollow East) yielded various ostracods assigned to nine species belonging to six genera: Cypridea verrucata Neustrueva, 1974, C. ihsienensis Hou, 1958, C. unicostata Galeeva, 1955, C. tumefacta Neustrueva, 1974, Yumenia cf. Y. oriformis Hou, 1958, Scabriculocypris subscalara Zhang and Chen in Ye et al., 2003, ?Trapezoidella sp., Candona sp., and Vlakomia ulanense Neustrueva, 1977. The biostratigraphic application of our taxonomic results suggests that the age of the Shinekhudag Formation is Barremian–Aptian. In addition, the ostracod fauna shows strong affinities to faunas from northeast China and potentially northwest China, providing evidence of faunal exchanges between these regions and southwest Mongolia. The new discovery of Vlakomia ulanense indicates that mid-Cretaceous (Albian) species in northeast China probably originated in Mongolia at the time of deposition of the Shinekhudag Formation. Two ostracod assemblages in the studied sections reflect that different paleoenvironment settings have existed during deposition; the Tsagaan Tsuvarga Section represents a shallow-littoral zone of athalassic (inland) saline lake under arid climate, and the dominance of cypridoideans of the Oshih Hollow East Section is indicative of ephemeral water bodies.","PeriodicalId":50098,"journal":{"name":"Journal of Paleontology","volume":"97 1","pages":"612 - 630"},"PeriodicalIF":1.4,"publicationDate":"2023-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45701048","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}
Abstract. Patagorbitestella new genus is here proposed to include two extant and one fossil species: P. ponderi (Linse, 2002) new combination, P. patagonica (Simone and Zelaya, 2004) new combination, and P. leonensis new species, the last described from the Punta Entrada Member of Monte León Formation (50°21′25.4”S, 68°53′05.9″W, Aquitanian to lower Burdigalian, lower Miocene). A protoconch sculptured with distinctive microscopic spiral threads serves as a per se diagnostic shell character for the new genus. Patagorbitestella n. gen. constitutes a distinctive lineage of orbitestellid gastropods inhabiting exclusively the Magellanic Region at least since the early Miocene. This is the first fossil record of Orbitestellidae in South America.
{"title":"New insight into Cenozoic Orbitestellidae (Gastropoda: Heterobranchia) from the Magellanic Region based on lower Neogene and Recent species","authors":"Javier Di Luca, M. Griffin, G. Pastorino","doi":"10.1017/jpa.2023.8","DOIUrl":"https://doi.org/10.1017/jpa.2023.8","url":null,"abstract":"Abstract. Patagorbitestella new genus is here proposed to include two extant and one fossil species: P. ponderi (Linse, 2002) new combination, P. patagonica (Simone and Zelaya, 2004) new combination, and P. leonensis new species, the last described from the Punta Entrada Member of Monte León Formation (50°21′25.4”S, 68°53′05.9″W, Aquitanian to lower Burdigalian, lower Miocene). A protoconch sculptured with distinctive microscopic spiral threads serves as a per se diagnostic shell character for the new genus. Patagorbitestella n. gen. constitutes a distinctive lineage of orbitestellid gastropods inhabiting exclusively the Magellanic Region at least since the early Miocene. This is the first fossil record of Orbitestellidae in South America.","PeriodicalId":50098,"journal":{"name":"Journal of Paleontology","volume":"97 1","pages":"558 - 565"},"PeriodicalIF":1.4,"publicationDate":"2023-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48569214","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}
{"title":"JPA volume 97 issue 2 Cover and Front matter","authors":"","doi":"10.1017/jpa.2023.18","DOIUrl":"https://doi.org/10.1017/jpa.2023.18","url":null,"abstract":"","PeriodicalId":50098,"journal":{"name":"Journal of Paleontology","volume":" ","pages":"f1 - f2"},"PeriodicalIF":1.4,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44716818","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}
Katie M. Maloney, Dakota P. Maverick, J. Schiffbauer, G. Halverson, S. Xiao, M. Laflamme
Abstract. Proterozoic eukaryotic macroalgae are difficult to interpret because morphological details required for proper phylogenetic studies are rarely preserved. This is especially true of morphologically simple organisms consisting of tubes, ribbons, or spheres that are commonly found in a wide array of bacteria, plants, and even animals. Previous reports of exceptionally preserved Tonian (ca. 950–900 Ma) fossils from the Dolores Creek Formation of Northwestern Canada feature enough morphological evidence to support a green macroalgal affinity. However, the affinities of two additional forms identified on the basis of the size distribution of available specimens remain undetermined, while the presence of three unique algal forms supports other reports of increasing algal diversity in the early Neoproterozoic. Archaeochaeta guncho new genus new species is described as a green macroalga on the basis of its well-preserved morphology consisting of an unbranching, uniseriate thallus with uniform width throughout and possessing an elliptical to globose anchoring holdfast. A larger size class of ribbon-like forms is interpreted as Vendotaenia sp. A third size class is significantly smaller than Archaeochaeta n. gen. and Vendotaenia, but in the absence of clear morphological characters, it remains difficult to assign. As Archaeochaeta n. gen. and Vendotaenia represent photoautotrophic taxa, these findings support the hypothesis of increasing morphological complexity and phyletic diversification of macroalgae during the Tonian, leading to dramatic changes within benthic marine ecosystems before the evolution of animals.
摘要元古代真核巨藻很难解释，因为系统发育研究所需的形态学细节很少被保存下来。对于由管状、带状或球形组成的形态简单的生物体来说尤其如此，这些生物体通常存在于各种各样的细菌、植物甚至动物中。先前关于加拿大西北部Dolores Creek组保存完好的Tonian(约950-900 Ma)化石的报道，有足够的形态学证据支持绿色大藻的亲缘关系。然而，根据现有标本的大小分布确定的另外两种形式的亲和力仍未确定，而三种独特的藻类形式的存在支持了新元古代早期藻类多样性增加的其他报告。古毛藻(Archaeochaeta guncho)新属新种被描述为一种保存完好的绿色大藻，其形态由无分支、单列的菌体组成，整个菌体具有均匀的宽度，并具有椭圆形到球形的锚定支架。带状形态的一个较大的尺寸类被解释为Vendotaenia sp.。第三个尺寸类明显小于Archaeochaeta n. gen.和Vendotaenia，但由于缺乏明确的形态特征，仍然难以确定。由于Archaeochaeta n. gen和Vendotaenia是光自养分类群，这些发现支持了大型藻类在Tonian时期形态复杂性和种类多样化的增加，导致底栖海洋生态系统在动物进化之前发生了巨大变化的假设。
{"title":"Systematic paleontology of macroalgal fossils from the Tonian Mackenzie Mountains Supergroup","authors":"Katie M. Maloney, Dakota P. Maverick, J. Schiffbauer, G. Halverson, S. Xiao, M. Laflamme","doi":"10.1017/jpa.2023.4","DOIUrl":"https://doi.org/10.1017/jpa.2023.4","url":null,"abstract":"Abstract. Proterozoic eukaryotic macroalgae are difficult to interpret because morphological details required for proper phylogenetic studies are rarely preserved. This is especially true of morphologically simple organisms consisting of tubes, ribbons, or spheres that are commonly found in a wide array of bacteria, plants, and even animals. Previous reports of exceptionally preserved Tonian (ca. 950–900 Ma) fossils from the Dolores Creek Formation of Northwestern Canada feature enough morphological evidence to support a green macroalgal affinity. However, the affinities of two additional forms identified on the basis of the size distribution of available specimens remain undetermined, while the presence of three unique algal forms supports other reports of increasing algal diversity in the early Neoproterozoic. Archaeochaeta guncho new genus new species is described as a green macroalga on the basis of its well-preserved morphology consisting of an unbranching, uniseriate thallus with uniform width throughout and possessing an elliptical to globose anchoring holdfast. A larger size class of ribbon-like forms is interpreted as Vendotaenia sp. A third size class is significantly smaller than Archaeochaeta n. gen. and Vendotaenia, but in the absence of clear morphological characters, it remains difficult to assign. As Archaeochaeta n. gen. and Vendotaenia represent photoautotrophic taxa, these findings support the hypothesis of increasing morphological complexity and phyletic diversification of macroalgae during the Tonian, leading to dramatic changes within benthic marine ecosystems before the evolution of animals.","PeriodicalId":50098,"journal":{"name":"Journal of Paleontology","volume":"97 1","pages":"499 - 515"},"PeriodicalIF":1.4,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47090293","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}
Abstract. The first fossil Typhlocybinae inclusions from Eocene Rovno amber are described and illustrated. They include two new monotypic genera of the extinct tribe Protodikraneurini, Retrorsotettix n. gen. with type species R. vlaskini n. sp. and Protoparallaxis n. gen. with type species P. clavatus n. sp. Also described and illustrated are two new monotypic genera of the extant tribe Dikraneurini, Eodikraneura n. gen. with type species E. obscura n. sp. and Rovnodikra n. gen. with type species Rovnodikra longipes n. sp. Retrorsotettix is the oldest leafhopper known to exhibit a false eyespot and false leg markings on the forewing, representing an early acquisition of a defensive strategy against visual predators. Appearance of a small insect with false eyespots in the Eocene fossil record may reflect increased pressure by visual predators, especially crown ornithuromorph insectivorous birds. Such birds and small insect prey with false eyespots remain unknown in the Cretaceous. Eodikraneura exhibits a unique condition of the hind wing venation in which radius posterior and media anterior veins are confluent for a short distance but then diverge before separately reaching the submarginal vein. This presumably represents a morphological transition between the Protodikraneurini, in which hind-wing radius posterior and media anterior veins are completely separate and connected by a radial-medial crossvein, and Dikraneurini, in which radius posterior and media anterior veins are completely confluent distally. A key to genera of Protodikraneurini is provided.
{"title":"Typhlocybinae leafhoppers (Hemiptera, Cicadellidae) from Eocene Rovno amber reveal a transition in wing venation and a defensive adaptation","authors":"C. Dietrich, S. A. Simutnik, E. Perkovsky","doi":"10.1017/jpa.2023.3","DOIUrl":"https://doi.org/10.1017/jpa.2023.3","url":null,"abstract":"Abstract. The first fossil Typhlocybinae inclusions from Eocene Rovno amber are described and illustrated. They include two new monotypic genera of the extinct tribe Protodikraneurini, Retrorsotettix n. gen. with type species R. vlaskini n. sp. and Protoparallaxis n. gen. with type species P. clavatus n. sp. Also described and illustrated are two new monotypic genera of the extant tribe Dikraneurini, Eodikraneura n. gen. with type species E. obscura n. sp. and Rovnodikra n. gen. with type species Rovnodikra longipes n. sp. Retrorsotettix is the oldest leafhopper known to exhibit a false eyespot and false leg markings on the forewing, representing an early acquisition of a defensive strategy against visual predators. Appearance of a small insect with false eyespots in the Eocene fossil record may reflect increased pressure by visual predators, especially crown ornithuromorph insectivorous birds. Such birds and small insect prey with false eyespots remain unknown in the Cretaceous. Eodikraneura exhibits a unique condition of the hind wing venation in which radius posterior and media anterior veins are confluent for a short distance but then diverge before separately reaching the submarginal vein. This presumably represents a morphological transition between the Protodikraneurini, in which hind-wing radius posterior and media anterior veins are completely separate and connected by a radial-medial crossvein, and Dikraneurini, in which radius posterior and media anterior veins are completely confluent distally. A key to genera of Protodikraneurini is provided.","PeriodicalId":50098,"journal":{"name":"Journal of Paleontology","volume":"97 1","pages":"366 - 379"},"PeriodicalIF":1.4,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46286155","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}
Heyo Van Iten, R. Gašparič, T. Hitij, T. Kolar-Jurkovšek, B. Jurkovšek
Sphenothallus Hall, 1847, one of the most widely distributed and longest ranging genera in the fossil record, has been documented from all systems of the Paleozoic Erathem except the Permian (Table 1), although it has been stated (e.g., Choi, 1990; Bolton, 1994; Fatka et al., 2012) that the genus also occurs in that system. At present the first appearance of this epibenthic, polypoid medusozoan cnidarian lies in Cambrian Stage 3, while the previously known youngest occurrences are in the Pennsylvanian System. Sphenothallus has been found in numerous formations on all continents except Australia and Antarctica. It occurs in a variety of marine facies ranging from shallow nearshore to deep offshore and has even been found in strata of coastal lacustrine origin, probably as an allochthonous element (Lerner and Lucas, 2011). Many of the rock units known to contain Sphenothallus also contain conulariids (Table 1), an extinct group of marine scyphozoans that may have been closely related to Sphenothallus (Van Iten et al., 1992, 1996). Van Iten et al. (1992) interpreted Sphenothallus as a medusozoan cnidarian of uncertain class-level affinities, but later Dzik et al. (2017) documented internal peridermal structures that may be homologous to similar features in the periderm of coronate scyphozoans (see for example illustrations in Van Iten, 1992, and Van Iten et al., 1996).
Sphenothallus Hall，1847，是化石记录中分布最广、范围最长的属之一，除二叠纪外，古生代的所有系统都有记录（表1），尽管有人指出（例如，Choi，1990；Bolton，1994；Fatka等人，2012）该属也出现在该系统中。目前，这种表海底、息肉状水母类的首次出现在寒武纪第3阶段，而之前已知的最年轻的出现在宾夕法尼亚系。除澳大利亚和南极洲外，在所有大陆的许多地层中都发现了鞘翅目化石。它存在于从浅近海到深近海的各种海洋相中，甚至在沿海湖泊成因的地层中发现，可能是一种外来元素（Lerner和Lucas，2011）。许多已知含有鞘翅目的岩石单元也含有圆锥虫（表1），圆锥虫是一种已灭绝的海洋镰刀形目动物，可能与鞘翅目有密切关系（Van Iten等人，19921996）。Van Iten等人（1992）将Sphenothallus解释为具有不确定类水平亲缘关系的水母类，但后来Dzik等人（2017）记录了内部皮周结构，这些结构可能与冠状病毒scyphozoans的皮周中的类似特征同源（例如，见Van Iten，1992和Van Iten et al.，1996中的插图）。
{"title":"First Report of Sphenothallus Hall (Cnidaria, Medusozoa) from the Mesozoic Erathem (Upper Triassic, Slovenia)","authors":"Heyo Van Iten, R. Gašparič, T. Hitij, T. Kolar-Jurkovšek, B. Jurkovšek","doi":"10.1017/jpa.2023.1","DOIUrl":"https://doi.org/10.1017/jpa.2023.1","url":null,"abstract":"Sphenothallus Hall, 1847, one of the most widely distributed and longest ranging genera in the fossil record, has been documented from all systems of the Paleozoic Erathem except the Permian (Table 1), although it has been stated (e.g., Choi, 1990; Bolton, 1994; Fatka et al., 2012) that the genus also occurs in that system. At present the first appearance of this epibenthic, polypoid medusozoan cnidarian lies in Cambrian Stage 3, while the previously known youngest occurrences are in the Pennsylvanian System. Sphenothallus has been found in numerous formations on all continents except Australia and Antarctica. It occurs in a variety of marine facies ranging from shallow nearshore to deep offshore and has even been found in strata of coastal lacustrine origin, probably as an allochthonous element (Lerner and Lucas, 2011). Many of the rock units known to contain Sphenothallus also contain conulariids (Table 1), an extinct group of marine scyphozoans that may have been closely related to Sphenothallus (Van Iten et al., 1992, 1996). Van Iten et al. (1992) interpreted Sphenothallus as a medusozoan cnidarian of uncertain class-level affinities, but later Dzik et al. (2017) documented internal peridermal structures that may be homologous to similar features in the periderm of coronate scyphozoans (see for example illustrations in Van Iten, 1992, and Van Iten et al., 1996).","PeriodicalId":50098,"journal":{"name":"Journal of Paleontology","volume":"97 1","pages":"764 - 772"},"PeriodicalIF":1.4,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41730614","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}
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