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Morphology, Phylogeny and Taxonomy of Osteolepiform Fish

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Morphology, Phylogeny and Taxonomy of Osteolepiform Fish An international monograph series of palaeontology and FOSSILS stratigraphy STRATAAND Number 61 • September 2016 Morphology, phylogeny and taxonomy of osteolepiform fish Ulf J. Borgen and Hans A. Nakrem Notes for authors Please consult the editor at an early stage regarding the suitability of the Copyright. – The Lethaia Foundation owns the copyright to Fossils and Strata topic, technical requirements, and financing. Final acceptance for publica- and licenses it to John Wiley & Sons Inc. The authors must declare in writing tion, however, will not be made until the manuscript has been refereed. the transfer of all rights to copyright to the Foundation. The author(s) will be Detailed instructions for the preparations and organisation of manu- asked to complete a copyright transfer agreement at the time of acceptance scripts are available on the Lethaia Foundation and John Wiley & Sons Inc. of the manuscript. web pages. These should be followed prior to submission of manuscripts. These standards are introduced with Fossils and Strata 59, 2013. They Submission of manuscripts are different from those published earlier in the series and incorporate a number of changes. They thus replace previous versions of the guide. Fossils and Strata accepts printed manuscripts. Thematic or multiple contri- butions should be submitted electronically including the manuscript, figures Instructions to authors and tables. Fossils and Strata publishes original research papers such as monographs, Paper submission. – Two paper copies, including all illustrations and tables, collections of thematic papers and/or a collection of papers that originated must be submitted, together with all computer-generated files prepared on from international conferences. Submitted manuscripts are considered for readable media. For safety, the authors should retain a further copy. Double- publication on the understanding that they have not been submitted or space all text. accepted for publication elsewhere. Send the manuscript to: Fossils and Strata, Dr. Svend Stouge, Geological Manuscripts. – Manuscripts should be written clearly and concisely and Museum, Øster Voldgade 5–7, DK-1350 Copenhagen K, Denmark. E-mail: conform to the general style of the monograph series. [email protected]. All contributions should be written in British (UK) English. Authors who are unfamiliar with English are encouraged to seek help of a competent Manuscript processing linguist prior to submission. A list of independent suppliers of editing services can be found at www.blackwellpublishing.com/bauthor/english_language.asp The initial submitted manuscript is sent to referees. On the basis of the Fossils and Strata follows the S1 (Systeme International d’Unities) units referees’ reports, the editor will decide whether to publish the manuscript wherever possible. and the modifications that will be required. Fossils and Strata accepts monographs with systematic taxonomy and the The author receives galley proofs and page proofs. The corrected accuracy of synonymies together with high-quality illustrations are a high proofs should be returned to the Production Editor. The editor and priority for the journal. Manuscripts that are inadequately prepared and do publisher take no responsibility for errors in the proofs not discovered by the not follow the rules of nomenclature will be returned to the author. authors. Morphology, phylogeny and taxonomy of osteolepiform fi sh by Ulf J. Borgen and Hans A. Nakrem Acknowledgements Financial support for the publication of this issue of Fossils and Strata was provided by the Lethaia Foundation and the Stensiö Foundation Contents Introduction ................................................................................................1 Position of pineal foramen .......................................................203 General taxonomy .......................................................................................2 Shape of pineal openings ..........................................................204 ‘Crossoptgerygii’ and ‘Rhipidistia’......................................................... 2 Size of pineal fenestra and presence of pineal plates ...........204 Osteolepiform subdivisions .................................................................. 3 Sensory canals ................................................................................204 Terminology ............................................................................................ 4 Pitlines .............................................................................................205 Cranial roof .........................................................................................4 Parietal shield ......................................................................................206 Endocranium .................................................................................... 13 Relative lengths of fronto-ethmoidal and parietal shields ......206 Dermal bones in mouth roof .........................................................13 Shape of parietal shield .................................................................207 Lower jaw ..........................................................................................14 Proportions .................................................................................207 Operculo-gular bones...................................................................... 15 Protruding posterior margin ...................................................209 Upper Palaeozoic fossil locality in the Oslo Region ............................16 Position of spiracular incision .................................................212 Stratigraphy ........................................................................................... 16 Relative length of the spiracular incision ..............................213 Descriptions ............................................................................................... 18 Parietals............................................................................................214 Material, methods and repository ......................................................18 Shape of parietals .......................................................................214 Genus Askerichthys n. gen. ............................................................ 20 Parietal structures ......................................................................214 Askerichthys heintzi n. sp. ..........................................................20 Intertemporals ................................................................................215 Genus Megalichthys Agassiz, 1835 ................................................ 62 Shape of interpemporal ............................................................215 Megalichthys cf. M. hibberti Agassiz, 1835............................... 62 Anterior intertemporal margin and process in post- Megalichthys pygmaeus Tranquair, 1879 .................................97 Devonian taxa ...........................................................................216 Megalichthys syndentolaminaris n. sp. .................................... 99 Anterior intertemporal processes in Devonian forms .........222 Genus Latvius Jarvik, 1948 ..........................................................100 On the function of the intracranial joint ...............................223 Latvius grewingki (Gross, 1933) ..............................................101 Lateral shelf of intertemporal ..................................................223 Latvius deckerti Jensen, 1966 ..................................................114 Ventral surface of intertemporal .............................................224 Latvius sp. Jensen, 1966 ............................................................121 Supratemporals ...............................................................................228 Latvius cf. L. niger Jensen, 1973 ..............................................128 Shape............................................................................................228 Genus Osteolepis Agassiz, 1835 ....................................................130 Ventral surface and lateral margin ..........................................228 Osteolepis macrolepidotus Agassiz, 1835 ................................131 Spiracular structures ......................................................................231 Genus Gyroptychius McCoy, 1848 ..............................................131 Extension of the spiracular opening .......................................231 Gyroptychius milleri (Jarvik, 1948) ........................................131 Types of spiracular openings ...................................................232 Gyroptychius groenlandicus Jarvik, 1950a ............................141 Possible muscle insertions around the spiraculum ..............233 Morphologic comparisons and discussions ........................................160 Extratemporal (= postspiraculars) ..............................................236 Fronto-ethmoidal shield ...................................................................160 Sensory canals ................................................................................236 General shape ............................................................................160 Course of sensory canal ...........................................................236 Interpremaxilla ..............................................................................162
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