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Early Devonian Microvertebrates from the Tyers-Boola Area of Centrai Victoria, Australia

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Bollettino della Società Paleontologica Italiana Modena, Novembre 1999 Early Devonian microvertebrates from the Tyers-Boola area of centrai Victoria, Australia Alison BASDEN Department of Earth and Planetary Sciences Macquarie University KEY WO RDS - Microvertebrates, Systematics, Early Devonian, Australia. ABSTRA CT- The vertebrate microfauna from the Coopers Creek Formation, centra! Victoria, comprises platelets and derma! bo ne fragments from brachythoracid and acanthothoracid placoderms, rare chondrichthyan remains, scales of the acanthodians Trundlelepis cervicostulata, Nostolepoides platymarginata, Gomphonchus? bogongensis, Nostolepis sp., Acanthoides sp., Cheiracanthoides sp_. and Poracanthodes sp., acanthodian fin spines, and rare osteichthyan teeth. Accompanying conodonts date the fauna as sulcatus-kindlei zones (Pragian, Early Devonian). Comparisons with coeva! faunas from southeast Australia reveal many common taxa. RIASSUNTO- [Microvertebrati del Devoniano inferiore nell'area di Tyers-Boola nel Victoria centrale, Australia]- La microfauna a vertebrati rinvenuta nella Formazione di Coopers Creek, nel Victoria centrale comprende placche palata/i e placche derma/i di placodermi brachitoracidi e acantotoracidi, rari resti di condricti, scaglie degli acantodi Trundlelepis cervicostulata, Nostolepoides platymarginata, Gomphonchus? bogongensis, Nostolepis sp., Acanthoides sp., Cheiracanthoides sp. e Poracanthodes sp., spine caudali di acantodi e rari denti di osteicti. l conodonti rinvenuti negli stessi livelli consentono di datare la fauna alle biozone a sulcatus-kindlei (Pragiano, Devoniano inf). Un confronto con faune coeve del! Australia sud-orientale evidenzia come molti taxa siano comuni. INTRODUCTION determined by conodonts, chitinozoans or corals, are indicated in Text-fìg. 2. Microvertebrates are becoming increasingly useful for both biostratigraphic correlation and palaeo- environmental interpretation. The systematic collection GEOLOGY AND PREVIOUS WORK of vertebrate microremains and conodonts together, in sections spanning severa! conodont zones, is a more The Coopers Creek Limestone at Tyers (Text-fìg. precise technique than isolated spot sampling for 3) comprises limestones with interbedded mudstones, establishing the stratigraphic range of microvertebrate sandstones an d conglomerates. Detailed geology of the species, as previously demonstrated by De Pomeroy area is given by Mawson & Talent ( 1994). Relifìsch & (1994, 1996) and Basden (1999). Webb (1993) interpret the Coopers Creek Limestone The present study documents the fìsh microfossils as a primarily carbonate fan deposited in deep water. in the Coopers Creek Limestone at Tyers and Boola Conodonts recovered from the Coopers Creek quarries in centrai Victoria (Text-fìg. 1), and dates the Limestone atTyers and Boola quarries indicate an age microvertebrate occurrences using the accompanying spanning the sulcatus to dehiscens zones (Mawson & conodonts. The Tyers-Boola vertebrate microfauna is Talent, 1994, fìg. 2); Tyers quarry is the type locality compared with similar faunas from other Early for the zonally signifìcant Eognathodus sulcatus Philip, Devonian limestones in southeastern Australia: while the incoming of lambda and mu morphs of E. Windellama (Mawson, 1986; Basden et al., in press) sulcatus indicates kindlei Zone, an d that of Polygnathus and Burrinjuck (Schultze, 1968; 0rvig, 1969; White, dehiscens dehiscens Philip & Jackson indicates dehiscens 1978; Giffìn, 1980; Long & Young, 1988; Mawson et Zone. Conodonts were recovered consistently al., 1992; Basden, 1999; Basden et al., in press) in throughout the two sections sampled (TQ and BOO, southern New South Wales; around Wellington see Mawson & Talent, 1994, fìg. 4), whereas most of (Mawson et al., 1988; Basden et al., in press) and the vertebrate microremains from the same residues Condobolin (Pickett & McClatchie, 1991; Pickett, described here occur only in the lower part of the 1992; Burrow, 1996, 1997) in centrai New South sections. Wales; Buchan in eastern Victoria (Long, 1984; Other studies in the Tyers-Boola area have revealed Mawson, 1987; Basden, 1999; Basden et al., in press); a diverse invertebrate fauna: tabulate corals and a and Point Hibbs in western Tasmania (Burrow et al., cyanophyte (Chapman, 1907); rugose and tabulate 1998). Stratigraphic ranges of these other limestones, corals, brachiopods and stromatoporoids (Philip, 1960, 528 A. BASDEN ___ .... - .. ----.. ·-····- $: -·-.. --.. -...... -.............. -.................... ,_ ..... o soo km Cl) r::: serotinus z Vi.. (ij E mversus !: w ...... _.. ,_ ............................. ·-·-·-·-""""""' :B ........... _.... ,_,_ §!, ............ .. ......................... z <C ... ...... _........... _.. o ....... 1l --·-1- .......... .. .............. ........ .. z dehiscens l'Il :9 o 1---+__:::==-"'--+- E I w> r::: pireneae Jg C.. o o,.. i l! ' ..J> ... a: l <C sutcatus al 3 l' w -al- QUEENSLAND ..r::: >o i ....c g __ .1----. ....1 eurekaensis ' OMOOOOM""''""''"''''' 'MOOMM ' O"OMO" """''''"''"""-''"'"'""'MOOOHOOO""""""""'"'"'"'.. '"' MOOOO U"O""'"'''"""""'"''''"'"'' woschmidti ! BRISBANE r---------·......,,- Text-fìg. 2 - Strarigraphic ranges of Early Devonian secrions in 1 NE\v' SOUTH \v'ALES sourheastern Australia used in rhis srudy. j L Condobolin • 1 ._ · SYDNEY ·, '-, • • / \v'indellama COMPARISON OF TYERS-BOOLA FAUNA .......... ..__, Burrinjuck WITH OTHER EARLY DEVONlAN • VICTORIA • \..) SOUTHEAST AUSTRALlAN FAUNAS r' Buchan Tyers The microvertebrate fauna recovered from the two sections at Tyers Quarry and nearby Boola Quarry is dominated by scales of climatiid and ischnacanthid acanthodians, with less abundant brachythoracid and acanthothoracid placoderm platelets and hone fragments, and acanthodian spines. Chondrichthyans Texr-fìg. l - Map of eastern Australia showing location of Early and osteichthyans are represented by rare teeth or tooth Devonian strata menrioned in rhis study. fragments, but no thelodont remains have been recovered. Text-fig. 4 shows the distribution and abundance of the vertebrate microremains from the two sections. Plates assigned to the/etalichthyid Wijdeaspis sp. (P l. l, figs. 14-15) exten the range for 1962); conodonts (Philip, 1965; Philip & Pedder, this genus, previously known only from the Emsian, 1967; Mawson & Talent, 1994); and chitinozoans down to sulcatus Zone (Pragian). The age of the two (Winchester-Seeto, 1993). sections studied falls within the previously reported Philip's (1965) description of two types of stratigraphic range for all other taxa described. acanthodian scales and fin spines was both the first A comparison of the vertebrate microfaunas from account of vertebrate microfossils from the area and the Tyers-Boola area and other Early Devonian the first record of isolated acanthodian scales from acid limestones in southeastern Australia reveals common residues in Australia. Philip considered scales of o ne of elements (Text-fig. 5). This is not unexpected, since these two types strongly resembled the cosmopolitan the localities are of similar age and in relatively dose genus Nostolepis; Turner (1991, pls. 3B, 3C) renamed proximity - Tyers is no further than 500 km from any two of the scales figured by Philip (1965, pl. 8, figs. of the other localities. All the faunas are dominated by 38, 40) as nostolepid and Machaeracanthus sp. Similar acanthodian and placoderm remains, with chon- scales have since been recovered from Early Devonian drichthyans, osteichthyans and thelodonts rare or sites in centrai New South Wales, and have been absent. All the taxa atTyers-Boola have been reported assigned by Burrow ( 1997) to Nostolepoides from at least two of the other localities. Limestones platymarginata (see below). Fragments resembling the from centrai NSW, being the most comparable in age fin spine figured by Philip (1965, Pl. 8, fig. 42) have to Tyers-Boola (see Text-fig. 2), have the most similar been recovered in the present study (Pl. 2., figs. 12, faunas. The most obvious differences between ali rhe 13; see below). localities are the relative lack of diversiry of the EARLY DEVONIAN MICROVERTEBRATES FROM AUSTRALIA 529 Windellama vertebrate fauna, and the presence or a borehole in Western Australia. lndeed, turiniid absence of thelodont scales. scales occur in localites across Australia from Early No thelodont remains have been recovered from unti! early Late Devonian (Turner, 1993, 1997). Tyers-Boola, Windellama or Pt Hibbs. However, Studies from regions as widely separated as the Baltic severa! centrai NSW localities, Buchan an d Burrinjuck and Australia indicate that nearshore sediments ali have turiniid scales very much like Turinia commonly comprise a high proportion of thelodont australiemis, originally described by Gross ( 1971) from scales relative to acanthodian scales (e.g. Marss & Einasto, 1978; Turner, 1986, 1991, 1995a, 1995b, 1997; Burrow, 1997). The absence of thelodont scales from the faunas a t Tyers-Boola, Windellama and Point Hibbs, and their presence in the otherwise-similar faunas from Buchan, Burrinjuck and the centrai New South Wales localities, possibly indicates that the depositional environment at Tyers-Boola, Windellama and Point Hibbs was in deeper water. Evidence of water depth is also provided by the abundance and composition of both conodont and invertebrate faunas. The greater abundance of conodonts from the Tyers-Boola area, compared with other Early Devonian horizons in southeastern Australia, is considered indicative of deeper water
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  • A New Lower Devonian Arthrodire (Placodermi) from the NW Siberian Platform

    A New Lower Devonian Arthrodire (Placodermi) from the NW Siberian Platform

    Estonian Journal of Earth Sciences, 2013, 62, 3, 131–138 doi: 10.3176/earth.2013.11 A new Lower Devonian arthrodire (Placodermi) from the NW Siberian Platform Elga Mark-Kurik Institute of Geology at Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia; [email protected] Received 24 August 2012, accepted 5 November 2012 Abstract. A new genus and species of arthrodires, Eukaia elongata (Actinolepidoidei, Placodermi), is described from the Lower Devonian, ?Pragian of the Turukhansk region, NW Siberian Platform. A single specimen of the fish, a skull roof, comes probably from the lower part of the Razvedochnyj Formation. The occurrence of an actinolepidoid arthrodire in the Early Devonian of this area of Siberia is unexpected. Eukaia shows some distant relationship with the genus Actinolepis, but several features indicate similarity to representatives of other arthrodires. Key words: actinolepidoid arthrodire, placoderm, Lower Devonian, ?Pragian, NW Siberian Platform. INTRODUCTION (Fig. 1). The first two units are Lochkovian in age, the lower part of the Razvedochnyj Fm belongs to the Pragian The northwestern part of the Siberian Platform in the and the upper part of the Razvedochnyj Fm plus the lower Russian Arctic is well known for rich and amphiaspidid- part of the Mantura Fm to the Emsian (Matukhin 1995). dominated Early Devonian fish faunas. One of the The Zub Fm (up to 150 m thick) consists of carbonaceous- important areas where these faunas have been discovered argillaceous and sulphate rocks. Invertebrates and fossil is the near-Yenisej zone of the Tunguska syneclise fishes, e.g. a cyathaspidid Steinaspis, are comparatively (Krylova et al.
  • A Primitive Megalichthyid Fish (Sarcopterygii, Tetrapodomorpha)

    A Primitive Megalichthyid Fish (Sarcopterygii, Tetrapodomorpha)

    A primitive megalichthyid fi sh (Sarcopterygii, Tetrapodomorpha) from the Upper Devonian of Turkey and its biogeographical implications Philippe JANVIER UMR 5143 du CNRS, Département Histoire de la Terre, Muséum national d’Histoire naturelle, case postale 38, 57 rue Cuvier, F-75231 Paris cedex 05 (France) [email protected] and Department of Palaeontology, The Natural History Museum, Cromwell Road, London SW7 5BD (United Kingdom) Gaël CLÉMENT UMR 5143 du CNRS, Département Histoire de la Terre, Muséum national d’Histoire naturelle, case postale 38, 57 rue Cuvier, F-75231 Paris cedex 05 (France) [email protected] Richard CLOUTIER Département de Biologie, Université du Québec à Rimouski, 300 allée des Ursulines, Rimouski, Québec, G5L 3A1 (Canada) [email protected] Janvier P., Clément G. & Cloutier R. 2007. — A primitive megalichthyid fi sh (Sarcopterygii, Tetrapodomorpha) from the Upper Devonian of Turkey and its biogeographical implications. Geodiversitas 29 (2) : 249-268. ABSTRACT KEY WORDS Sarcopterygii, Th e vertebrate fauna of the red sandstone of Pamucak-Sapan Dere Unit of Tetrapodomorpha, the Upper Antalya Nappe (Frasnian?, Turkey) is reviewed on the basis of new Megalichthyidae, “Osteolepiformes”, material. Th e association of the phyllolepid Placolepis with the arthrodire Holo- Devonian, nema in this fauna strongly suggests a Frasnian age or, at any rate, older than Turkey, the Famennian. Th e unique osteolepiform sarcopterygian of this fauna is here biogeography, new genus, described in detail and referred to Sengoerichthys ottoman n. gen., n. sp., which new species. is considered as the most generalized megalichthyid known to date. GEODIVERSITAS • 2007 • 29 (2) © Publications Scientifi ques du Muséum national d’Histoire naturelle, Paris.
  • Ptyctodontid Fishes (Vertebrata, Placodermi) from the Late Devonian Gogo Formation, Western Australia, with a Revision of the European Genus Ctenurella 0Rvig, 1960

    Ptyctodontid Fishes (Vertebrata, Placodermi) from the Late Devonian Gogo Formation, Western Australia, with a Revision of the European Genus Ctenurella 0Rvig, 1960

    Ptyctodontid fishes (Vertebrata, Placodermi) from the Late Devonian Gogo Formation, Western Australia, with a revision of the European genus Ctenurella 0rvig, 1960 John A. LONG Department of Earth and Planetary Sciences, The Western Australian Museum, Francis Street, Perth, Western Australia, 6000 (Australia) Long J. A. 1997. — Ptyctodontid fishes (Vertebrata, Placodermi) from the Late Devonian Gogo Formation, Western Australia, with a revision of the European genus Ctenurella 0rvlg, 1960. Geodiversitas 19 (3) : 515-555. ABSTRACT A new, almost complete specimen of the ptyctodontid placoderm Campbellodus decipiens Miles et Young, 1977 enables description of the skull toof, trunk shield, visceral skeleton, pelvic girdle, dermal scale cover, and parts of the vertebtal column. A new reconstruction of the head shield of Ctenurella gladbachensis 0rvig, 1960 from Bergisch-Gladbach permits this taxon to be genetically defined from the Gogo species pteviously referred to that genus. The Gogo form is here referred to Austroptyctodus n.g. A new spe­ KEYWORDS cimen of Austroptyctodus gardineri Miles et Young, 1977, together with new Ptyctodontida, observations of Chelyophorus verneuili Agassiz, 1844 and Ctenurella gladba­ Devonian, chensis 0rvig, 1960, shows new information fot the endocranium, the hyoid Placodermi, Gogo, arch and visceral skeleton, identifying the previously identified "metaptery- Australia, goid" elements as paired nasal bones. The large visceral skeleton bone poste­ Austroptyctodus n.g., rior to the jaw joint in ptyctodontids is here identified as an elongated Ctenurella, Chelyophorus. interhyal. RESUME Une nouvelle description du toit crânien, de la cuirasse thoracique, du sque­ lette viscéral, de la ceinture pelvienne, de l'écaillure et de quelques éléments de la colonne vertébtale est proposée à partit d'un nouveau spécimen sub­ complet du ptyctodonte Campbellodus decipiens Miles et Young, 1977.