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New Placoderm Fishes from the Early Devonian B U C H a N G R O U P , E a S T E R N V I C T O R

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PROC. R. SOC. VICT. vol. 96, no. 4, 173-186, Decemb er 1984 NEW PLACODERM FISHES FROM THE EARLY DEVONIAN BUCHAN GROUP, EASTERN VICTORIA By J ohn A. L ong Department of G eology, Australian National Universi ty, P.O . Box 4, Canberra, A.C .T. 2601 A bstract : Three new placoderms are described from the McLarty Member of the Murrindal Limestone (Early Devonian, Buchan Group). M urrindalaspis wallacei gen. el sp. nov. is a palae- acanthaspidoid characterized by having a high m edia n dorsal crest and lacking a m edian ventral keel. M. bairdi sp. nov. differs from the type species in having a low median dorsal crest and a median ventral groove. Taem asosteus m aclarliensis sp. nov. differs from the type species T. novaustrocam bricus W hite in the shape of the posterior region of the nuchal plate, the presence of canals between the infranuch al pits and the posterior face o f the nuchal plate, th e shape of the paranuchal plate, and the developm en t of the apronic lam ina of the anterior lateral plate. The placoderm s, A renipiscis westoUi Young, Errolosleus cf. E. goodradigbeensis Young, W ijdeaspis warrooensis Young, are recorded from the Buchan Group indicati ng close sim ilarity to the ichthyofauna of the contem poraneous M urrumbidgee Group, New Sout h W ales. Few fossil fishes have been studied from the Early been described from the Murrumbidgee and Mulga Devonian Buchan Group. M cCoy (1876) described some Downs Groups in New South Wales and the Cravens placoderm plates from this region as Asterolepis ornata Peak Beds in Queensland, with numerous sites yielding var. australis, which Chapman (1916) queried when m icrovertebrate assemblages (Long 1982, 1983b, Turn er presenting a description of a placoderm skull from et at. 1981, Long & Turner 1984). Buchan. Chapman identified this specimen as a phly- Specimens are housed in the following institutions: ctaenioid, Phlyctaenaspis confertituberculatus, but Hills CPC, Commonwealth Palaeontological Collections, (1936b) assigned the skull to Coccosteus. Stensio (1945) Bureau of Mineral Resources, Canberra; MUGD, recognized differences between the parasphenoid of Geology Department, M elbourne University; and NMV, Coccosteus and the Buchan specimen and erected M useum of Victoria, M elbourne. Buchanosteus for the latter. Additional material of Buchanosteus has since been found from the M urrum­ SYSTEMATIC PALAEONTOLOGY bidgee G roup, New South W ales, making this genus on e Subclass P lacodermi M cCoy 1848 of the best known Early Devonian euarthrodires (W hite Superorder P etalichthyomorpha Miles & Young 1977 1952, W hite & Toombs 1972, Young 1979). The only Order P etalichthyida Jaekel 1911 other fish described from Buchan is a mandible of the dipnoan Dipnorhynchus sussmilchi (Hills 1936a, Thom ­ W iJdeaspis warrooensis Young 1978 son & Campbell 1971). This paper describes placoder m Fig. 4C ' fish material recovered from the Buchan Group durin g M aterial : A piece of trunk shield com prising the right Monash University third year geology field mapping spinal plate and a small sliver of the anterior lateral trips as well as some found by geology honours stud ents plate. NMVP159825, collected Dr. R . E. Fordyce, from both M elbourne and M onash Universities (Long February, 1981. 1983 b). O ccurrence : The uppermost division of the M cLarty The material was prepared using acetic acid with Member of the Murrindal Limestone, immediately dilute polyvinylbuterol to strengthen the exposed b one. northeast of Rocky Camp Quarry, north of Buchan. All specimens were found in the uppermost McLarty M ember or ihe lowermost Rocky Camp Member of the R emarks : The specimen is identified as belonging to M urrindal Limestone, with the richest concentration of Wijdeaspis because the spinal shows a relatively high vertebrates occurring near the contact of the M cLar ty num ber of ornam ental ridges (9-10) which are form ed of and Rocky Camp M embers on the eastern face of Rocky closely packed tubercles arranged in rows. On this basis Camp Hill (Fig. 1). In addition to the macrovertebr ate Young (1978, p. 112) distinguished Wijdeaspis spinal remains rich concentrations of microvertebrate foss ils plates from those of Lunaspis species. The Buchan were recovered from the residues during preparation , specimen is almost identical with that of Wijdeaspis and these have been forwarded to Dr. S. Turner warrooensis figured by Young (1978, figs 2E, 8B). (Queensland Museum) for detailed study. Amongst these are several types of acanthodian and elasm obr anch Order R henanida Broili 1930 scales similar to forms described from the M urrum­ Suborder P alaeacanthaspidoidei Miles & Young 1977 bidgee G roup by Giffin (1980). Recently a jaw of a new Family W eeja sper a spida e W hite 1978 ischnacanthid acanthodian was found in residues fro m D ia g nosis : Palaeacanthaspidoids having a well the Rocky Camp Member (under current study by the developed median dorsal crest on the median dorsal author). Lower Devonian macrovertebrates have also plate, which has a posterior face with a smooth med ial 173 174 JOHN A. LONG BUCHAN D ia g nosis : A weejasperaspid of m oderate size having a median dorsal plate with a sm ooth ventral surface w hich may have a median ventral groove developed; dermal ornam entation of short ridges, approxim ately one-th ird as long as broad, on the dorsal surfaces with pointed stellate tubercles densely concentrated near the an terior and posterior margins; median dorsal crest develope d; a short dorsal transverse sensory line canal situated at the anterior base of the median dorsal crest; the poste rior face of the median dorsal crest with a smooth media n prominence throughout. T y pe S pec ies : Murrindalaspis wallacei sp. nov. R emarks : This palaeacanthaspid is similar to Wee­ jasperaspis gavini W hite (1978) but differs in the absence of the median ventral keel on the median dorsal pla te. Palaeacanthaspis Stensio 1944 also possesses a median dorsal crest but differs from both Murrindalaspis and Weejasperaspis in possessing a large nutritive foramen for the crest on the ventral surface of the median dorsal plate, and by its simple tubercular ornam entation. Of the remaining described palaeacanthaspids none has a well developed median crest; where the median dorsa l plate is unknown (Brindabellaspis Y oung 1980, Romun- dina Orvig 1975, Kimaspis Mark-Kurik 1973a, Kolymaspis in Denison 1978) Murrindalaspis is dis­ tinguished by the characteristic dermal ornam entati on. M urrindalaspis wallacei sp. nov. Figs 2A, D, E, G, 3, 8C, D E tymology : After Mr. M. Wallace, Dept. Geology, University of Tasmania, who discovered several fish es from the Buchan area in 1982, including the type specimen of Murrindalaspis gen. nov., and kindly allowed me to study the material. D ia g nosis : A member of Murrindalaspis with a median dorsal plate having a high median dorsal crest whic h is strongly curved posteriorly and tapers narrowly at its apex. Ventral surface of median dorsal plate smooth , Fig. 1 —Locality map of placoderm fossils collected in the and there are paired prominences developed at the Buchan region. G eology from Teichert & Talent (1958 ). posterior end of the ventral surface near the base of the crest. Ratio of median dorsal crest height/plate le ngth prominence. M edian dorsal plate with a B /L index ap­ approxim ately 64. proximately 80. Coarse ornamentation consisting of H olotype : M UGD6066 (Figs 2A, D, E , G, 3), an almost short ridges and pointed tubercles each with well d efined complete median dorsal plate from the top of the grooves. M cLarty Member of the M urrindal Limestone from the R emarks : W hite’s diagnosis (1978) has been m odified to vicinity of Rocky Camp Quarry, north of Buchan incorporate features of the new genus from Buchan. (Fig. 1). Weejasperaspis White 1978 and Murrindalaspis gen. D escr ipt ion : The holotype is almost complete, missing nov. are similar in the proportions of the m edian d orsal only the top of the crest and a small part of the left plate, in their median dorsal crests and in the mor ­ anterolateral corner. It bears a high, slender median phology of the derm al ornam entation; they differ ch iefly dorsal crest (cr.d) which starts approximately 28% of in the well-developed median ventral ridge on Wee­ the plate length from the anterior margin, and exte nds jasperaspis only, and in the size of tubercles of the backwards beyond the level of the posterior margin (Fig. external ornam ent. 3). In profile the crest is strongly curved, being propor­ tionately much narrower than the broad crest of Wee­ M urrindalaspis gen. nov. jasperaspis (Fig. 8). The anterior m argin of the plate has E tymology : A fter the settlement of M urrindal, north of a short median convexity and lateral to this region the Buchan. anterior margin extends forward at an angle of abou t NEW PLACODERM FISHES Fig. 2 —M urrindalaspis gen. nov., Emsian, Buchan. A , D, E, G, M . wallacei sp. nov., M UGD6066. H olotype m edian dorsal plate in A , ventral, D , post erior, E, right lateral and G, dorsal views, x l. B, C, F, H . M . bairdi sp. nov., NM VP59892. H olotype median dorsal plate in B, posterior, C, ventral, and F, right lateral views. H , detail of derm al ornam entat ion. B, x2; C, F, x l; H, x4. All specimens whitened with am m onium chloride. 176 JOHN A. LONG 40° to the lateral margin of the plate. There is a narrow D ia g nosis : A Murrindalaspis having a median dorsal overlap platform (ant.oa) along the extent of the plate which bears a low median dorsal crest.
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    Family-Group Names of Fossil Fishes

    European Journal of Taxonomy 466: 1–167 ISSN 2118-9773 https://doi.org/10.5852/ejt.2018.466 www.europeanjournaloftaxonomy.eu 2018 · Van der Laan R. This work is licensed under a Creative Commons Attribution 3.0 License. Monograph urn:lsid:zoobank.org:pub:1F74D019-D13C-426F-835A-24A9A1126C55 Family-group names of fossil fishes Richard VAN DER LAAN Grasmeent 80, 1357JJ Almere, The Netherlands. Email: [email protected] urn:lsid:zoobank.org:author:55EA63EE-63FD-49E6-A216-A6D2BEB91B82 Abstract. The family-group names of animals (superfamily, family, subfamily, supertribe, tribe and subtribe) are regulated by the International Code of Zoological Nomenclature. Particularly, the family names are very important, because they are among the most widely used of all technical animal names. A uniform name and spelling are essential for the location of information. To facilitate this, a list of family- group names for fossil fishes has been compiled. I use the concept ‘Fishes’ in the usual sense, i.e., starting with the Agnatha up to the †Osteolepidiformes. All the family-group names proposed for fossil fishes found to date are listed, together with their author(s) and year of publication. The main goal of the list is to contribute to the usage of the correct family-group names for fossil fishes with a uniform spelling and to list the author(s) and date of those names. No valid family-group name description could be located for the following family-group names currently in usage: †Brindabellaspidae, †Diabolepididae, †Dorsetichthyidae, †Erichalcidae, †Holodipteridae, †Kentuckiidae, †Lepidaspididae, †Loganelliidae and †Pituriaspididae. Keywords. Nomenclature, ICZN, Vertebrata, Agnatha, Gnathostomata.
  • Fossil Fishes (Arthrodira and Acanthodida) from the Upper Devonian Chadakoin Formation of Erie County, Pennsylvania1

    Fossil Fishes (Arthrodira and Acanthodida) from the Upper Devonian Chadakoin Formation of Erie County, Pennsylvania1

    Fossil Fishes (Arthrodira and Acanthodida) from the Upper Devonian Chadakoin Formation of Erie County, Pennsylvania1 KEVIN M. YEAGER2, Department of Geosciences, Edinboro University of Pennsylvania, Edinboro, PA 16444 ABSTRACT. Several fossil fish were discovered in 1994 in the Upper Devonian Chadakoin Formation, near Howard Falls, just outside of Edinboro, Erie County, Pennsylvania. These fossils are fragmentary in nature and have been described based on their morphology. They are identified as the median dorsal plate of the large arthrodire Dunkleosteus terrelli Newberry, 1873, and the spines of probable acanthodian fishes. The identification of the median dorsal plate of Dunkleosteus represents a new occurrence of the genus. In general, these discoveries are of scientific interest because very little is known about the composition of the fish fauna that inhabited the Devonian shallow seas of northwestern Pennsylvania. OHIO J. SCI. 96 (3): 52-56,1996 INTRODUCTION Pennsylvania were deposited in a shallow water en- This study was an outgrowth of geologic field map- vironment. The shallower bottom sediments were oxy- ping being conducted in the Howard Falls area near genated by waves and currents, and supported a variety Edinboro, Pennsylvania. In August 1994, the first of of scavengers. several vertebrate fossil specimens were discovered. The Nonetheless, reduced preservation potential alone first specimen was excavated, reconstructed, and identi- does not explain why fossil fishes are poorly known fied by specialists from the Pennsylvania State Museum, from Pennsylvania. The Devonian rocks of southern Harrisburg. Since that time, four more vertebrate speci- New York were deposited in shallow waters also, but mens have been collected. These specimens were have yielded a diverse fish fauna (Eastman 1907).
  • Comments on Distribution and Taphonomy of Devonian Placoderms in the Holy Cross Mountains, Poland

    Comments on Distribution and Taphonomy of Devonian Placoderms in the Holy Cross Mountains, Poland

    Comments on distribution and taphonomy of Devonian placoderms in the Holy Cross Mountains, Poland Piotr Szrek Taphonomy, stratigraphical occurrences and geographical distribution of Devonian placoderms in the Holy Cross Mountains described by former researchers is revised. Four main types of preservation states occur in the placoderm fossils of that region. Fossil preservation depends on geodynamic processes. Mechanical damage appears to be the main factor explaining the final state of preservation. For most of the previously described as well as the new specimens, the occurrences were dated biostratigraphically by palynomorphs and conodonts. The taxonomic distribution of placoderms in space and time within the Devonian strata in the Holy Cross Mountains correlates well with the Devonian nekton revolution, but it is also controlled by the regional palaeoecology and local synsedimentary tectonics of the carbonate platform. • Key words: Placodermi, Devonian, distribution, taphonomy, Holy Cross Mountains, Poland. SZREK, P. 2020. Comments on distribution and taphonomy of Devonian placoderms in the Holy Cross Mountains, Poland. Bulletin of Geosciences 95(1), 23–39 (7 figures, 2 tables). Czech Geological Survey, Prague. ISSN 1214-1119. Manuscript received June 4, 2019; accepted in revised form December 16, 2019; published online January 21, 2020; issued March 31, 2020. Piotr Szrek, Polish Geological Institute–National Research Institute, 4 Rakowiecka Street, 00-975 Warsaw, Poland; piotr. [email protected] & University of Warsaw, Faculty of Geology, Żwirki i Wigury Street 93, 02-089 Warsaw, Poland Placodermi McCoy, 1848 (armoured fishes) are a group areas. However, Kulczycki worked prior to the publication of early jawed vertebrates that appeared in the Silurian of Wegener’s theory of continental drift, resulting in some period and reached maximum diversification during the erroneous palaeogeographic conclusions, but his cor- Devonian.