Pub Date : 2015-11-01DOI: 10.1080/02693445.2019.1642002
W. Kennedy
ABSTRACT PART I A total of 34 species, assigned to 19 genera belonging to the suborders Phylloceratina, Lytoceratina and Ammonitina are described. One species is new. Nine are from the Upper Turonian, three from the Santonian (of which one is already present in the Coniacian), one from the Lower Campanian, 20 from the Upper Campanian and one from the Lower Maastrichtian.
{"title":"The Ammonoidea of the Upper Chalk. Part 1","authors":"W. Kennedy","doi":"10.1080/02693445.2019.1642002","DOIUrl":"https://doi.org/10.1080/02693445.2019.1642002","url":null,"abstract":"ABSTRACT PART I A total of 34 species, assigned to 19 genera belonging to the suborders Phylloceratina, Lytoceratina and Ammonitina are described. One species is new. Nine are from the Upper Turonian, three from the Santonian (of which one is already present in the Coniacian), one from the Lower Campanian, 20 from the Upper Campanian and one from the Lower Maastrichtian.","PeriodicalId":134015,"journal":{"name":"Monographs of the Palaeontographical Society","volume":"150 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120994245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-11-01DOI: 10.1080/02693445.2015.11963956
C. W. Wright, W. Kennedy
ABSTRACT Part 6 deals with material additional to that described in previous parts, including an account of the genus Schloenbachia.
第6部分讨论了前几部分所描述的额外材料，包括对Schloenbachia属的描述。
{"title":"The Ammonoidea of the Lower Chalk Part 6","authors":"C. W. Wright, W. Kennedy","doi":"10.1080/02693445.2015.11963956","DOIUrl":"https://doi.org/10.1080/02693445.2015.11963956","url":null,"abstract":"ABSTRACT Part 6 deals with material additional to that described in previous parts, including an account of the genus Schloenbachia.","PeriodicalId":134015,"journal":{"name":"Monographs of the Palaeontographical Society","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134321113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-10-01DOI: 10.1080/02693445.2014.11963953
Adam S. Smith, R. Benson
ABSTRACT This paper describes the holotype of Rhomaleosaurus thorntoni (NHMUK PV R4853) from the upper part of the Whitby Mudstone Formation (Toarcian) of Kingsthorpe Hollow, Northamptonshire, England. Rhomaleosaurus thorntoni possesses the following autapomorphies: (1) dorsomedian foramen with mediolaterally narrow slit-like morphology situated well anterior to the external nares; (2) humerus long relative to skull length and body length; (3) distal end of humerus greatly expanded both preaxially and postaxially. Several other characters present in Rhomaleosaurus thorntoni cannot be determined in other Rhomaleosaurus species, so these may also be autapomorphies of R. thorntoni. A summary of previous phylogenetic analyses of Plesiosauria shows that the relationships among the three main clades (Rhomaleosauridae, Pliosauridae, Plesiosauroidea) are unclear and further investigation is required to understand the evolution of early plesiosaurians.
{"title":"Osteology of Rhomaleosaurus Thorntoni (Sauropterygia: Rhomaleosauridae) from the Lower Jurassic (Toarcian) of Northamptonshire, England","authors":"Adam S. Smith, R. Benson","doi":"10.1080/02693445.2014.11963953","DOIUrl":"https://doi.org/10.1080/02693445.2014.11963953","url":null,"abstract":"ABSTRACT This paper describes the holotype of Rhomaleosaurus thorntoni (NHMUK PV R4853) from the upper part of the Whitby Mudstone Formation (Toarcian) of Kingsthorpe Hollow, Northamptonshire, England. Rhomaleosaurus thorntoni possesses the following autapomorphies: (1) dorsomedian foramen with mediolaterally narrow slit-like morphology situated well anterior to the external nares; (2) humerus long relative to skull length and body length; (3) distal end of humerus greatly expanded both preaxially and postaxially. Several other characters present in Rhomaleosaurus thorntoni cannot be determined in other Rhomaleosaurus species, so these may also be autapomorphies of R. thorntoni. A summary of previous phylogenetic analyses of Plesiosauria shows that the relationships among the three main clades (Rhomaleosauridae, Pliosauridae, Plesiosauroidea) are unclear and further investigation is required to understand the evolution of early plesiosaurians.","PeriodicalId":134015,"journal":{"name":"Monographs of the Palaeontographical Society","volume":"74 9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120897107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-10-01DOI: 10.1080/02693445.2014.11963954
S. Donovan, F. E. Fearnhead
ABSTRACT This is the first monographic study of the Devonian Crinoidea of the British Isles for over 100 years; most museum specimens were collected in the 19th Century. In this Part 1, we describe the Subclass Camerata, including the orders Diplobathrida (five genera, six species) and Monobathrida (nine genera, 27 species), including those taxa in open nomenclature. The generic and, particularly, specific diversities of the diplobathrids of the type area of the Devonian are low compared with the Silurian and Mississippian of the British Isles; specimens are few, poorly preserved and difficult to identify. Monobathrids are more numerous, better preserved and occur in a wider variety, particularly the Middle Devonian Hexacrinites spp. of the Torquay Limestone Formation, south Devon. New taxa described herein are left in open nomenclature, particularly Hexacrinites sp. C (based on a pluricolumnal), camerate spp. A-D (imperfect theca and crowns), and distal spiral and planar coiled attachments. Platycrinus? anguliferus (Whidborne) is reassigned to the hexacrinitid genus Oehlerticrinus Le Menn.
这是100多年来对不列颠群岛泥盆纪海百合科的首次专题研究;大多数博物馆标本都是在19世纪收集的。本文第一部分介绍了照相机亚纲，包括双重蕨目(5属6种)和单重蕨目(9属27种)，包括开放命名的分类群。泥盆纪模式区双足纲的属类多样性，特别是特异多样性与英伦三岛志留系和密西西比系相比较低;标本很少，保存不良，难以辨认。单足纲数量更多，保存得更好，种类也更广，尤其是德文郡南部托基石灰岩组的中泥盆世海泥质组。本文所描述的新分类群保留了开放式命名法，特别是Hexacrinites sp. C(基于多柱)，照相机sp. a - d(不完善的膜和冠)，以及远端螺旋状和平面卷曲状附着体。Platycrinus吗?鳗属(惠特伯恩)被重新划归到勒曼鳗属。
{"title":"The British Devonian Crinoidea Part 1, Introduction and Camerata","authors":"S. Donovan, F. E. Fearnhead","doi":"10.1080/02693445.2014.11963954","DOIUrl":"https://doi.org/10.1080/02693445.2014.11963954","url":null,"abstract":"ABSTRACT This is the first monographic study of the Devonian Crinoidea of the British Isles for over 100 years; most museum specimens were collected in the 19th Century. In this Part 1, we describe the Subclass Camerata, including the orders Diplobathrida (five genera, six species) and Monobathrida (nine genera, 27 species), including those taxa in open nomenclature. The generic and, particularly, specific diversities of the diplobathrids of the type area of the Devonian are low compared with the Silurian and Mississippian of the British Isles; specimens are few, poorly preserved and difficult to identify. Monobathrids are more numerous, better preserved and occur in a wider variety, particularly the Middle Devonian Hexacrinites spp. of the Torquay Limestone Formation, south Devon. New taxa described herein are left in open nomenclature, particularly Hexacrinites sp. C (based on a pluricolumnal), camerate spp. A-D (imperfect theca and crowns), and distal spiral and planar coiled attachments. Platycrinus? anguliferus (Whidborne) is reassigned to the hexacrinitid genus Oehlerticrinus Le Menn.","PeriodicalId":134015,"journal":{"name":"Monographs of the Palaeontographical Society","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132246496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-03-01DOI: 10.1080/02693445.2013.11963951
M. Mohibullah, M. Williams, J. Zalasiewicz
ABSTRACT The Late Ordovician ostracod fauna recorded from the Girvan district, south-west Scotland, comprises 54 species from 26 genera and 15 families, but includes 22 species described in open nomenclature and a further 17 that are considered as nomina dubia. The ostracods include representatives of the podocope suborders Palaeocopina, Binodicopina, Leiocopina and Metacopina, and the new genera and species Danemestrinus scotus n. gen. et sp., Leperditella girvanensis n. sp. and Krausella jonesiana n. sp. are described. The fauna includes several species that allow inter-continental correlation with the Late Ordovician succession of North America, including the Sandbian species Eurychilina sunbloodensis, Balticella deckeri, Baltonotella parsispinosa and Hippula ventrospinosa. The Katian species Kinnekullea comma has correlative value between Scotland, Ireland, England and the East Baltic. Biogeographically, the Girvan ostracod fauna of Sandbian age shows strong affinities at species-level with the fauna of palaeocontinental Laurentia, but from the early Katian onwards there are species level links with the Baltic region, and some common taxa at generic and species-level with palaeocontinental Avalonia.
{"title":"Late Ordovician Ostracods of the Girvan District, South-West Scotland","authors":"M. Mohibullah, M. Williams, J. Zalasiewicz","doi":"10.1080/02693445.2013.11963951","DOIUrl":"https://doi.org/10.1080/02693445.2013.11963951","url":null,"abstract":"ABSTRACT The Late Ordovician ostracod fauna recorded from the Girvan district, south-west Scotland, comprises 54 species from 26 genera and 15 families, but includes 22 species described in open nomenclature and a further 17 that are considered as nomina dubia. The ostracods include representatives of the podocope suborders Palaeocopina, Binodicopina, Leiocopina and Metacopina, and the new genera and species Danemestrinus scotus n. gen. et sp., Leperditella girvanensis n. sp. and Krausella jonesiana n. sp. are described. The fauna includes several species that allow inter-continental correlation with the Late Ordovician succession of North America, including the Sandbian species Eurychilina sunbloodensis, Balticella deckeri, Baltonotella parsispinosa and Hippula ventrospinosa. The Katian species Kinnekullea comma has correlative value between Scotland, Ireland, England and the East Baltic. Biogeographically, the Girvan ostracod fauna of Sandbian age shows strong affinities at species-level with the fauna of palaeocontinental Laurentia, but from the early Katian onwards there are species level links with the Baltic region, and some common taxa at generic and species-level with palaeocontinental Avalonia.","PeriodicalId":134015,"journal":{"name":"Monographs of the Palaeontographical Society","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127409432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-03-01DOI: 10.1080/02693445.2013.11963952
P. Copestake, Ben Johnson
ABSTRACT The complete, fully cored Lower Jurassic (Hettangian, Sinemurian, Pliensbachian, Toarcian) succession from the Llanbedr (Mochras Farm) Borehole, North Wales, the thickest known British section, has yielded a diverse and well preserved foraminiferal fauna, comprising 270 species and subspecies which are described and illustrated. An additional nine taxa, not encountered at Mochras, are also described. This typical European Boreal Atlantic foraminiferal fauna is dominated by members of the Lagenida, with the Ceratobuliminoidea, Miliolida, Spirillinina, Involutinina, Buliminida and Textulariida as important accessory groups. The Ceratobuliminoidea and Miliolida are unusually diverse, with Reinholdella and Ophthalmidium being notably abundant. The presence of the Family Oberhauserellidae is significant. A benthonic foraminiferal biozonation scheme for the Lower Jurassic, comprising 16 biozones and tied to the standard ammonite-based chronostratigraphy, is described in detail. It is recognizable across the northern European Boreal province, and is applicable to subsurface hydrocarbon exploration of the UK continental shelf and onshore Europe. Three new genera (Duoplanum, Extonia and Haynesella) are described as well as 19 new species (Citharina sherringtoni, Duoplanum inaequale, D. leve, Glomospirella liassica, Lagena? haeusleri, L. semisulcata, Lagenammina pseudofusiformis, L. tangentia, Loxostomum liassicum, Marginulina turneri, Neobulimina bangae, Nodosaria pseudoclaviformis, Ophthalmidium strictum, Reinholdella? mochrasensis, R. robusta, Reussoolina? lacrimaforma, Semiinvoluta excelsa, Tubinella pseudoinornata and Vinelloidea lordi), and 10 new subspecies (Berthelinella involuta striata, Ichthyolaria terquemi bamardi, I. terquemi mediumcostata, Lenticulina varians barnardi, Loxostomum liassicum liassicum, L. liassicum teres, Ophthalmidium macfadyeni tenuiloculare, Paralingulina cernua ssp. A, Reinholdella margarita dorsoplana and R. pachyderma humilis). Two further species are renamed as Nodosaria whittakeri and Paralingulina paranodosaria.
{"title":"Lower Jurassic Foraminifera from the Llanbedr (Mochras Farm) Borehole, North Wales, UK","authors":"P. Copestake, Ben Johnson","doi":"10.1080/02693445.2013.11963952","DOIUrl":"https://doi.org/10.1080/02693445.2013.11963952","url":null,"abstract":"ABSTRACT The complete, fully cored Lower Jurassic (Hettangian, Sinemurian, Pliensbachian, Toarcian) succession from the Llanbedr (Mochras Farm) Borehole, North Wales, the thickest known British section, has yielded a diverse and well preserved foraminiferal fauna, comprising 270 species and subspecies which are described and illustrated. An additional nine taxa, not encountered at Mochras, are also described. This typical European Boreal Atlantic foraminiferal fauna is dominated by members of the Lagenida, with the Ceratobuliminoidea, Miliolida, Spirillinina, Involutinina, Buliminida and Textulariida as important accessory groups. The Ceratobuliminoidea and Miliolida are unusually diverse, with Reinholdella and Ophthalmidium being notably abundant. The presence of the Family Oberhauserellidae is significant. A benthonic foraminiferal biozonation scheme for the Lower Jurassic, comprising 16 biozones and tied to the standard ammonite-based chronostratigraphy, is described in detail. It is recognizable across the northern European Boreal province, and is applicable to subsurface hydrocarbon exploration of the UK continental shelf and onshore Europe. Three new genera (Duoplanum, Extonia and Haynesella) are described as well as 19 new species (Citharina sherringtoni, Duoplanum inaequale, D. leve, Glomospirella liassica, Lagena? haeusleri, L. semisulcata, Lagenammina pseudofusiformis, L. tangentia, Loxostomum liassicum, Marginulina turneri, Neobulimina bangae, Nodosaria pseudoclaviformis, Ophthalmidium strictum, Reinholdella? mochrasensis, R. robusta, Reussoolina? lacrimaforma, Semiinvoluta excelsa, Tubinella pseudoinornata and Vinelloidea lordi), and 10 new subspecies (Berthelinella involuta striata, Ichthyolaria terquemi bamardi, I. terquemi mediumcostata, Lenticulina varians barnardi, Loxostomum liassicum liassicum, L. liassicum teres, Ophthalmidium macfadyeni tenuiloculare, Paralingulina cernua ssp. A, Reinholdella margarita dorsoplana and R. pachyderma humilis). Two further species are renamed as Nodosaria whittakeri and Paralingulina paranodosaria.","PeriodicalId":134015,"journal":{"name":"Monographs of the Palaeontographical Society","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127063505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-12-31DOI: 10.1080/25761900.2022.12131819
A. Smith, C. W. Wright
ABSTRACT This part completes the systematic revision of the British Cretaceous echinoids with a review of the species belonging to the spatangoid family Micrasteridae. Eighteen species belonging to two genera, Roweaster nov. and Micraster, are described and illustrated and a key to the species is provided. Six of these species have not previously been recorded from the British Isles and one species, Micraster (Gibbaster) norfolkensis, is new. New plating diagrams are provided for these species. In addition a cassiduloid, Archiacia sp., and a new holasteroid, Pseudananchys speetonensis sp. nov., are described. Tables summarizing the stratigraphical and geographical distribution of all 222 British Cretaceous echinoids are provided.
摘要:本部分对英国白垩纪棘足类(spatangoid family microsteridae)的棘足类进行了系统的修订。本文描述并说明了属(Roweaster 11 .)和属(Micraster)两属的18种，并提供了种的检索表。其中六种以前没有在不列颠群岛记录过，其中一种是新发现的。为这些物种提供了新的镀层图。此外，还描述了一种cassiduoid, Archiacia sp.和一种新的全小行星Pseudananchys speetonensis sp. nov.。给出了222种英国白垩纪棘足类的地层和地理分布概况。
{"title":"British Cretaceous Echinoids","authors":"A. Smith, C. W. Wright","doi":"10.1080/25761900.2022.12131819","DOIUrl":"https://doi.org/10.1080/25761900.2022.12131819","url":null,"abstract":"ABSTRACT This part completes the systematic revision of the British Cretaceous echinoids with a review of the species belonging to the spatangoid family Micrasteridae. Eighteen species belonging to two genera, Roweaster nov. and Micraster, are described and illustrated and a key to the species is provided. Six of these species have not previously been recorded from the British Isles and one species, Micraster (Gibbaster) norfolkensis, is new. New plating diagrams are provided for these species. In addition a cassiduloid, Archiacia sp., and a new holasteroid, Pseudananchys speetonensis sp. nov., are described. Tables summarizing the stratigraphical and geographical distribution of all 222 British Cretaceous echinoids are provided.","PeriodicalId":134015,"journal":{"name":"Monographs of the Palaeontographical Society","volume":"2 9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120824562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-12-31DOI: 10.1080/25761900.2022.12131818
S. Donovan, Rosanne E. Widdison, D. N. Lewis, F. E. Fearnhead
ABSTRACT In Part 3, we describe the British Silurian crinoids of the subclass Camerata, including the orders Diplobathrida (five genera, nine species) and Monobathrida (12 genera, 34 species), and morphotaxa based on disarticulated columnals and pluricolumnals (four morphogenera, nine morphospecies), including those taxa left in open nomenclature. Six new nominal species of monobathrid are described, namely the periechocrinid Periechocrinus? bulbosus (Ramsbottom MS) sp. nov., the carpocrinids Carpocrinus verminosus Widdison sp. nov. and Carpocrinus ramsbottomi Widdison sp. nov., the eucalyptocrinitids Calliocrinus rugiferus (Ramsbottom MS) sp. nov. and Eucalyptocrinites aberrans Widdison sp. nov., and the hapalocrinid Cordylocrinus rugobrachialis (Ramsbottom MS) sp. nov. A new crinoid columnal morphospecies is named Floricolumnus (col.) lefewi Donovan sp. nov. In an addendum to Part 2, the dendrocrinid 'Dendrocrinus' obscurus sp. nov. is described (Middle Llandovery Newlands Farm Formation, Ayrshire). About 120 species of crinoid are identified from the Silurian of the British Isles including those in open nomenclature and columnal morphotaxa. Over half are known from the Much Wenlock Limestone Formation of Dudley, Worcestershire.
{"title":"The British Silurian Crinoidea","authors":"S. Donovan, Rosanne E. Widdison, D. N. Lewis, F. E. Fearnhead","doi":"10.1080/25761900.2022.12131818","DOIUrl":"https://doi.org/10.1080/25761900.2022.12131818","url":null,"abstract":"ABSTRACT In Part 3, we describe the British Silurian crinoids of the subclass Camerata, including the orders Diplobathrida (five genera, nine species) and Monobathrida (12 genera, 34 species), and morphotaxa based on disarticulated columnals and pluricolumnals (four morphogenera, nine morphospecies), including those taxa left in open nomenclature. Six new nominal species of monobathrid are described, namely the periechocrinid Periechocrinus? bulbosus (Ramsbottom MS) sp. nov., the carpocrinids Carpocrinus verminosus Widdison sp. nov. and Carpocrinus ramsbottomi Widdison sp. nov., the eucalyptocrinitids Calliocrinus rugiferus (Ramsbottom MS) sp. nov. and Eucalyptocrinites aberrans Widdison sp. nov., and the hapalocrinid Cordylocrinus rugobrachialis (Ramsbottom MS) sp. nov. A new crinoid columnal morphospecies is named Floricolumnus (col.) lefewi Donovan sp. nov. In an addendum to Part 2, the dendrocrinid 'Dendrocrinus' obscurus sp. nov. is described (Middle Llandovery Newlands Farm Formation, Ayrshire). About 120 species of crinoid are identified from the Silurian of the British Isles including those in open nomenclature and columnal morphotaxa. Over half are known from the Much Wenlock Limestone Formation of Dudley, Worcestershire.","PeriodicalId":134015,"journal":{"name":"Monographs of the Palaeontographical Society","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128109340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-12-31DOI: 10.1080/25761900.2022.12131817
D. H. Evans
ABSTRACT The cephalopod assemblages of the Lower Ordovician portion of the Durness Group of North-West Scotland are described and referred to 46 taxa across six orders and 15 families. A total of 30 genera are described, of which Expandocassinoceras and Augeoceras are new. Thirty-four species are described, although only 13 are named; of these, Pionoceras peachi, Allopiloceras bealachense and Allopiloceras lonachonense are new. A further nine taxa are treated in open nomenclature at the order or family level, and another three are regarded as indeterminate at the present time but are included here for completeness. The older cephalopod assemblages of the Durness Group (Sailmhor and Sangomore formations) are relatively sparse, but dominated by ellesmerocerids and bassleroceratids. By contrast, the younger-assemblages (in particular those of the Croisaphuill and Ben Suardal Limestone formations) are relatively abundant and dominated by endocerids, tarphycerids and orthoceratoids. The cephalopod assemblage appears to be strongly affiliated to those of western Newfoundland, Quebec, Ontario and New York State. Members of the Orthoceratoidea occur in the Durness Group at horizons somewhat older than those previously recorded from the south-western United States and are similar in age to occurrences in Avalonia (England and Wales). This suggests that whatever the earlier history of the Orthoceratoidea, a rapid diversification and dispersal appears to have taken place during the early Floian.
{"title":"The Lower Ordovician Cephalopod Faunas of the Durness Group, North-West Scotland","authors":"D. H. Evans","doi":"10.1080/25761900.2022.12131817","DOIUrl":"https://doi.org/10.1080/25761900.2022.12131817","url":null,"abstract":"ABSTRACT The cephalopod assemblages of the Lower Ordovician portion of the Durness Group of North-West Scotland are described and referred to 46 taxa across six orders and 15 families. A total of 30 genera are described, of which Expandocassinoceras and Augeoceras are new. Thirty-four species are described, although only 13 are named; of these, Pionoceras peachi, Allopiloceras bealachense and Allopiloceras lonachonense are new. A further nine taxa are treated in open nomenclature at the order or family level, and another three are regarded as indeterminate at the present time but are included here for completeness. The older cephalopod assemblages of the Durness Group (Sailmhor and Sangomore formations) are relatively sparse, but dominated by ellesmerocerids and bassleroceratids. By contrast, the younger-assemblages (in particular those of the Croisaphuill and Ben Suardal Limestone formations) are relatively abundant and dominated by endocerids, tarphycerids and orthoceratoids. The cephalopod assemblage appears to be strongly affiliated to those of western Newfoundland, Quebec, Ontario and New York State. Members of the Orthoceratoidea occur in the Durness Group at horizons somewhat older than those previously recorded from the south-western United States and are similar in age to occurrences in Avalonia (England and Wales). This suggests that whatever the earlier history of the Orthoceratoidea, a rapid diversification and dispersal appears to have taken place during the early Floian.","PeriodicalId":134015,"journal":{"name":"Monographs of the Palaeontographical Society","volume":"54 24","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120819284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2011-12-31DOI: 10.1080/25761900.2022.12131816
J. Lamsdell
ABSTRACT Stoermeropterus conicus (Eurypterida: Eurypterina), from the Telychian (upper Llandovery, Silurian) of the Pentland Hills, near Edinburgh, Scotland, is described from material originally assigned to three different species (Nanahughmilleria conica, Drepanopterus bembycoides and Drepanopterus lobatus). Two other existing eurypterid species, Hughmilleria lata from the Wenlock of Norway and Drepanopterus nodosus from the Pridoli of North America, are recognized as being congeneric with S. conicus, united principally by their possession of movable mesosomal spines on the mesosoma, genital spatulae and a bulbous telson 'boss'. Several characters support the assignment of Stoermeropterus to Moselopteridae, the most basal eurypterine clade, including its possession of a pediform appendage VI with a modified 'podomere' 7a and the possession of a coxal 'ear', which may represent the remains of a much-reduced exopod. Stoermeropterus conicus resolves phylogenetically as the most basal known eurypterine, and can aid in reconstructing the eurypterid ground plan. As such an attempt is made to reconstruct the characteristics that are plesiomorphic for Eurypterida through comparison with basal Eurypterina, Stylonurina, chasmataspidids and synziphosurines. Several characteristics previously thought to be autapomorphies of Stylonurina, such as a three-segmented genital operculum, are now shown to be plesiomorphic conditions in respect to Eurypterida as a whole, while other apparently derived characteristics, such as an epistoma and genital spatula, may be characters that are present in all eurypterids during the juvenile stage and are respectively either paedomorphically retained into adulthood or become hypertrophied in various species. Following the identification of a metastoma and genital appendage in some chasmataspidid species, the sole currently known eurypterid autapomorphy is identified as the fusion of the opercular plates of somites VIII and IX. Evolutionary relationships among the traditional 'merostome' groups are reviewed, primarily in light of segment articulations and the development of the appendage of somite VII. The concept that synziphosurines may represent a paraphyletic stem grade to a group inclusive of xiphosurids, chasmataspidids, eurypterids and arachnids is proposed.
{"title":"The Eurypterid Stoermeropterus Conicus from the Lower Silurian of the Pentland Hills, Scotland","authors":"J. Lamsdell","doi":"10.1080/25761900.2022.12131816","DOIUrl":"https://doi.org/10.1080/25761900.2022.12131816","url":null,"abstract":"ABSTRACT Stoermeropterus conicus (Eurypterida: Eurypterina), from the Telychian (upper Llandovery, Silurian) of the Pentland Hills, near Edinburgh, Scotland, is described from material originally assigned to three different species (Nanahughmilleria conica, Drepanopterus bembycoides and Drepanopterus lobatus). Two other existing eurypterid species, Hughmilleria lata from the Wenlock of Norway and Drepanopterus nodosus from the Pridoli of North America, are recognized as being congeneric with S. conicus, united principally by their possession of movable mesosomal spines on the mesosoma, genital spatulae and a bulbous telson 'boss'. Several characters support the assignment of Stoermeropterus to Moselopteridae, the most basal eurypterine clade, including its possession of a pediform appendage VI with a modified 'podomere' 7a and the possession of a coxal 'ear', which may represent the remains of a much-reduced exopod. Stoermeropterus conicus resolves phylogenetically as the most basal known eurypterine, and can aid in reconstructing the eurypterid ground plan. As such an attempt is made to reconstruct the characteristics that are plesiomorphic for Eurypterida through comparison with basal Eurypterina, Stylonurina, chasmataspidids and synziphosurines. Several characteristics previously thought to be autapomorphies of Stylonurina, such as a three-segmented genital operculum, are now shown to be plesiomorphic conditions in respect to Eurypterida as a whole, while other apparently derived characteristics, such as an epistoma and genital spatula, may be characters that are present in all eurypterids during the juvenile stage and are respectively either paedomorphically retained into adulthood or become hypertrophied in various species. Following the identification of a metastoma and genital appendage in some chasmataspidid species, the sole currently known eurypterid autapomorphy is identified as the fusion of the opercular plates of somites VIII and IX. Evolutionary relationships among the traditional 'merostome' groups are reviewed, primarily in light of segment articulations and the development of the appendage of somite VII. The concept that synziphosurines may represent a paraphyletic stem grade to a group inclusive of xiphosurids, chasmataspidids, eurypterids and arachnids is proposed.","PeriodicalId":134015,"journal":{"name":"Monographs of the Palaeontographical Society","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114181306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：