Reworked Devonian (Givetian-Frasnian) spores from a Permian glacially-derived sequence at Bacchus Marsh, Victoria

Emphanisporites rotatus McGregor emend. McGregor 1973 is a distinctive Devonian spore with a known primary source age range in Australia spanning the upper Givetian to early Frasnian (Middle to Late Devonian). This is the first record of the species from Victoria. It occurs as a reworked element in an Early Permian assemblage belonging to the Granularisporites confluens Zone derived from glacigene diamictite in the Bacchus Marsh area. As the predominant direction of Permian ice movement recorded in the Bacchus Marsh district was south-west to north-east, it is possible that the reworked spores were transported from Antarctica.

Late Palaeozoic sequence stratigraphy and brachiopod faunas of the Tarim Basin, Northwest China

This thesis deals with the stratigraphy and brachiopod systematic palaeontology of the latest Devonian (Famennian) to Early Permian (Kungurian) sedimentary sequences of the Tarim Basin, NW China. Brachiopod faunas of latest Devonian and Carboniferous age have been published or currently in press in the course of the Ph.D candidature and are herein appendixed, while the Early Permian brachiopod faunas are systematically described in this thesis. The described Early Permian brachiopod faunas include 127 species, of which 29 are new and 12 indeterminate, and six new genera (subgenera) are proposed; Tarimella, Bmntonella, Marginifera (Arenaria), Marginifera (Nesiotia), Baliqliqia and Ustritskia. A new integrated brachiopod biostratigraphical zonation scheme is proposed, for the first time, for the latest Devonian-Early Permian sequences of the entire Tarim Basin on the basis of this study as well as previously published information (including the Candidate's own published papers). The scheme consists of twenty three brachiopod acm biozones, most of which replace previously proposed assemblage or assemblage zones. The age and distribution of these brachiopod zones within the Tarim Basin and their relationships with other important fossil groups are discussed. In terms of regional correlations and biostratigraphical affinities, the Late Devonian to Early Carboniferous brachiopod faunas of the Tarim Basin are closest to those from South China, while the Late Carboniferous faunas demonstrate strong similarities to coeval faunas from the Urals, central Asia, North China and South China. During the Asselian-Sakmarian, strong faunal links between the Tarim Basin and those of the Urals persisted, while at the same time links with central Asia, North China and South China weakened. On the other hand, during the Artinskian-Kungurian times, affinities of the Tarim faunas with the Urals/Russian Platform rapidly reduced, when those with peri-Gondwana (South Thailand, northern Tibet) and South China increased. Thirty lithofacies (or microfacies) types of four facies associations are recognised for the Late Devonian to early Permian sediments. Based on detailed lithostratigraphy, biostratigraphy and facies analysis, 23 third-order sequences belonging to four supcrsequences are identified for the Late Devonian to Early Permian successions, from which sea-level fluctuation curves are reconstructed. The sequence stratigraphical analysis reveals that four major regional regressions, each marking a distinct supersequence boundary, can be recognised; they correspond to the end-Serpukhovian, end-Moscovian, late Artinskian and end-Kungurian times, respectively. The development of these sequences is considered to have been formed and regulated by the interplay of both eustasy and tectonism. Using the system tract of a sequence as the mapping time unit, a succession of 47 palaeogeographical maps have been reconstructed through the Late Devonian to Early Permian. These maps reveal that the Tarim Basin was first immersed by southwest-directed (Recent geographical orientation) transgression in the late Famennian after the Caledonian Orogeny. Since then, the basin had maintained its geometry as a large, southwest-mouthed embayment until the late Moscovian when most areas were the uplifted above sea-level. The basin was flooded again in late Asselian-Artinskian times when a new transgression came from a large epicontinental sea lying to its northwest. Thereafter, marine deposition was restricted to local areas (southwestern and northwestern margins until the late Kungurian, while deposition of continental deposits prevailed and continued through the Middle and late Permian into the Triassic.

Discovery of Early Devonian strata in northern Qiangtang, Tibet, and the establishment of the Pingshagou Formation

Although it is important to determine whether there exist sedimentary strata older than the Upper Permian in the northern Qiantang area in Tibet, there has been no report of such old strata in this area. During the geological mapping of the Mayigangri area, we discovered strata that contain the bivalves Eoschizodus roemeri (Beushausen), E. minor (Beushausen) , E. infiatus (Roemer), Actinodesma (Actinodesma) cf . maneiforme Sandberger, A . (Actindesma) cf . vespertilio Maurer, and the brachiopod Huananochonetes subquadratus Sun & Chen. These fossils indicate a late Early Devonian age (Emsian) , thus the strata represent the first discovered Lower Devonian rocks in northen Qiangtang, confirming the existence of strata older than the Upper Permian. A new stratigraphic term, the Pingshagou Formation , is introduced. The new data provide constraints on the tectonic, palaeogeographic, and palaeobiogeographic history of the north Qiangtang area in the Early Devonian.

A biogeographically mixed late Guadalupian (late Middle Permian) brachiopod fauna from an exotic limestone block at Xiukang in Lhaze county, Tibet

A total of 17 brachiopod species belonging to 15 genera are recorded from a limestone block of about 3×4 km2 in the Indus–Tsangbo suture zone at Xiukang in Lhaze County of Tibet. The brachiopod fauna generally indicates a Late Guadalupian age (late Wordian–Capitanian, late Middle Permian) based on its association with the Timorites-bearing ammonoid fauna and the presence of the brachiopod Urushtenoidea crenulata. Palaeobiogeographically, the fauna exhibits transitional/mixed characters between the warm-water Cathaysian and cold to temperate Gondwanan faunas and may have developed on a carbonate build-up or seamount on the oceanic crust.

Lopingian (Late Permian) stratigraphy, sedimentation and palaeobiogeography in southern Tibet

Investigations of the Permian-Triassic sections and limestone blocks scattered in the Indus-Tsangbo Suture Zone in southern Tibet show widespread distribution of the Lopingian strata. The Lopingian deposits mostly contain rich brachiopod fossils and characteristic conodonts of the Mesogondolella shenz Zone of latest Changhsingian age in the topmost part. Brachiopod assemblages are largely comparable with those known from the upper Wargal and Chhidru Formations of the Salt Range, Pakistan, the Zewan Formation of Kashmir, the upper part of the Kuling Group in Spiti of India and the Hardman Formation of Western Australia. A revised Lopingian (Late Permian) age is proposed for the Selong Group and its equivalents in southern Tibet. The Lopingian deposits in southern Tibet can be grouped into three different sedimentary types, each of which reflects different sedimentary environments from coastal to continental shelfal settings on the northern peri-Gondwanan margin. The Qubu-type sequence represents marine coastal and proximal barrier-lagoon sediments during a gradual sea-level rise. Micaceous sandstone and shale of regressive origin, with abundant palynomorphs and acritarches, developed during the Late Lopingian sea-level lowstand, which is followed by a major rapid transgression at the very end of Permian. The Selong-type sequence in the Selong area consists of bioclastic limestone and calcareous shale in the lower part, and crinoid grainstone in the upper part. The latter part is believed to have been formed in a high-energy inner shelf shoal setting. The Chitichun-type sequence, sporadically distributed along the Indus-Tsangbo suture zone as small limestone blocks, consists of pure bioclastic sparite with the ammonoid Cyclolobus fauna. It is interpreted as the break-up products of sea-mounts and/or small isolated carbonate build-ups developed on the outer shelfal settings.

Late Guadalupian (Middle Permian) Fusuline fauna from the Xiala formation in Xainza county, central Tibet : implication of the rifting time of the Lhasa Block

A fusuline fauna consisting of 9 species of 4 genera from the Xiala Formation of the Mujiucuo section, Xainza County, Tibet, China is described. The fusuline fauna is dominated by Nankinella and Chusenella and indicates a Midian (Late Guadalupian) age. The earliest record of fusuline fauna during the Midian in the Lhasa Block suggests that the block rifted later than the Qiangtang Block to the north and the Baoshan and Tengchong blocks to the east, all of which yield much earlier fusuline faunas of Yakhtashian (Artinskian) age, but had drifted away from Gondwana to a relatively warm temperate zone in the Late Guadalupian (Middle Permian).

A new genus of Rhynchonellid Brachiopod from the Lower Triassic of South China and Implications for timing the recovery of Brachiopoda after the end-Permian mass extinction

A new genus, Meishanorhynchia, is proposed based on new material from the Lower Triassic of the Meishan section, South China. It is of a late Griesbachian age based on both associated biozones (ammonoids and
bivalves) and radiometric dates of the intercalated volcanic ash beds. Comparison with both Palaeozoic and Mesozoic-Cenozoic-related genera suggests that it may represent the first radiation of progenitor brachiopods in the aftermath of the end-Permian extinction. The lowest brachiopod horizon that contains the genus is estimated to be about 250.1±0.3 Ma. This implies that the initial stage of recovery of Brachiopoda in the Early Triassic was probably about 1.3±0.3 myr after the major pulse of the end-Permian mass extinction (dated as 251.4±0.3 Ma). This is in agreement with Hallam's expectancy that biotic recovery typically begins within one million years or so of major mass extinctions, in contrast to current views on the end-Permian extinction event which propose that the recovery of most if not all biotic groups in the Early Triassic was severely delayed and only began about five million years after the end-Permian extinction.

The global mio-pliocene climatic equability and coastal ostracod faunas of southeast Australia

This study on the Mio–Pliocene ostracod successions of southeast Australia outlines several faunal events indicative of climate warming and/or increased rainfall events. Ostracod faunas associated with a late Late Miocene sea level rise event suggest that the climate of this time in southeast Australia was similar to, or slightly warmer than that of present day southeast Australia. However, it was probably wetter and significantly warmer than immediately preceding (mid Late Miocene) palaeoclimatic conditions within the region. Evidence for a change to wetter and warmer conditions during the late Late Miocene is seen in the appearance of various extant euryhaline and semi-thermophilic ostracod species in coastal ostracod faunas. The appearance of euryhaline species, which are mostly absent from older shallow marine Cenozoic strata of the Bass Strait hinterland, suggests a major influx of fresh water into coastal marine settings, which contributed to the initial phase of development of the southeast Australian late Neogene barrier coastline and associated marginal marine palaeoenvironments.

During the time interval latest Miocene to earliest Pliocene, and during the early Late Pliocene, two subsequent global sea level rise events are also preserved in the southeast Australian coastal plain. Many of the species present in ostracod faunas associated with these two events are the same as in older local late Late Miocene faunas. In earliest (?) Pliocene faunas, there is minor evidence for the reappearance of semi-thermophilic ostracods. Faunas of early Late Pliocene age often exhibit a conspicuous faunal dominance by, or large abundance of euryhaline species, indicating the particularly strong influence of fresh water influxes into coastal marine palaeoenvironments. This may reflect the presence of especially wet local temperate palaeoclimatic conditions during a time of equable global climates.

Succeeding estuarine, lagoonal and coastal embayment ostracod faunas of late Late Pliocene age are associated with marginal marine sediments that are interbedded with coastal dune aeolianites. This suggests an overall seaward retreat of marginal marine environments that was initiated by a major global sea level fall linked to the onset of cooler Late Pliocene and Quaternary global climates.

Guadalupian (Middle Permian) brachiopods from Sungai Toh, a Leptodus Shale locality in the Central Belt of Peninsular Malaysia. Part I: Lower Horizons

This work presents a systematic study of Permian Brachiopoda from the Sungai Toh Leptodus Shale locality, Pahang State, Peninsular Malaysia. This locality lies within the Central Belt of Peninsular Malaysia, a tectonic unit characterised.by tuffaceous sediments and limestones of Late Palaeozoic age. Two brachiopod-bearing horizons were studied in detail at this locality, the lower one (Horizon 2) bearing a mixed plant and invertebrate assemblage, including the brachiopods Urushtenoidea chaoi (CHING), Leptodus richthofeni KAYSER, Anidanthus cf. sinosus HUANG, Acosarina dorashamensis (SOKOLSKAJA), A. minuta (ABleH) and unidentifiable species of Linoproduetus, Neochonetes, and Strophalosiina. Horizon 3 contains a more abundant and diverse brachiopod fauna, comprising a total. of 57 species representing 47 genera, including Vediproductus punetatiformis (CHAO), Permianella typica HE & ZHU, Tranrennatia gratiosa (WAAGEN), Leptodus richthofeni KAYSER, Leptodus cf. tenuis (WAAGEN) and "Semibrachythyrina" [= Alphaneospirifer] cf. pyramidiformis LIANG. It is
suggested in this study that the age of the Sungai Toh locality is Capitanian (late Guadalupian) to possibly Wuchiapingian (early Lopingian),
as it appears to correlate well with the Lengwu fauna from Zhejiang in eastern China. The palaeobiogeographical affinities of the Sungai Toh fauna are interesting, mainly indicating strong Palaeo-equatorial affinities, while there are also some elements more typical of the cooler periGondwana
Region.

Permian brachiopods from the Tupe formation, San Juan Province, Precordillera, Argentina

The brachiopod fauna from the Tupe Formation at La Herradura Creek, located on the west flank of Perico Hill, San Juan Province, Argentina, palaeogeographically belongs to the western sector of the Paganzo basin ('Guandacol embayment'). The stratigraphical section of the Tupe Formation at La Herradura Creek is the stratotype of the Tivertonia jachalensis-Streptorhynchus inaequiornatus biozone, was previously regarded as being of Late Carboniferous age but here is assigned to the earliest Permian (Asselian). We describe and review the biozone assemblage, which consists of Streptorhynchus inaequiornatus, Tivertonia jachalensis, Kochiproductus sp., Costatumulus sp., Coronalosia argentinensis, Tupelosia paganzoensis, Trigonotreta pericoensis, Septosyringothyris sp. aff. Septosyringothyris jaguelensis and Crurithyris? sp. This brachiopod assemblage is related to Indian and Australian Early Permian faunas and its presence in the La Herradura Creek section provides new evidence in support of an Asselian (Early Permian) age for the Tivertonia jachalensis-Streptorhynchus inaequiornatus biozone. This assemblage is also important for intra- and inter-basinal correlation because several of its characteristic species have been identified from other sections of the Paganzo basin and the Riacuteo Blanco basin. The proposed age for this biozone is consistent with the age of palynological data from slightly above the marine faunas from the stratotype locality.

Uppermost Mississippian Brachiopods from the Basal Itaituba formation of the Amazon Basin, Brazil

This paper describes 19 brachiopod species (including six indeterminate species) in 15 genera and one indeterminate genus from the basal Itaituba Formation at the Caima Quarry 1 section of Itaituba, Amazon Basin, Brazil. The faunal correlations of the brachiopods and the associated fusulinids and conodonts indicate a late Chesterian (late Serpukhovian) age for the described fauna, therefore confirming for the first time the presence of uppermost Mississippian rocks in the Amazon Basin. A new species, Composita caimaensis, is created, and two species, Inflatia cf. gracilis and Marginovatia cf. catinulus, are described for the first time from the Amazon Basin. The Amazon brachiopods appear to be of strong affinity with coeval faunas of the North American midcontinent.

Early Triassic lingulidae and associated marine faunas in south China

The survival strategies of Early Triassic Lingulidae fauna and its associated shallow marine faunas across the end-Permian mass extinction 250 million years ago are discussed. Three new genera and nine new species are erected. A comprehensive database of all Lingulidae species through the Late Devonian to Present is also constructed.

Ontogeny of energy allocation reveals selective pressure promoting risk-taking behaviour in young fish cohorts

Given limited food, prey fishes in a temperate climate must take risks to acquire sufficient reserves for winter and/or to outgrow vulnerability to predation. However, how can we distinguish which selective pressure promotes risk-taking when larger body size is always beneficial? To address this question, we examined patterns of energy allocation in populations of age-0 trout to determine if greater risk-taking corresponds with energy allocation to lipids or to somatic growth. Trout achieved maximum growth rates in all lakes and allocated nearly all of their acquired energy to somatic growth when small in early summer. However, trout in low-food lakes took greater risks to achieve this maximal growth, and therefore incurred high mortality. By late summer, age-0 trout allocated considerable energy to lipids and used previously risky habitats in all lakes. These results indicate that: (i) the size-dependent risk of predation (which is independent of behaviour) promotes risk-taking behaviour of age-0 trout to increase growth and minimize time spent in vulnerable sizes; and (ii) the physiology of energy allocation and behaviour interact to mediate growth/mortality trade-offs for young animals at risk of predation and starvation.

Lower Permian brachiopods from Wasp Head Formation, Sydney Basin, southeastern Australia

Although there is a generally accepted framework for the Permian marine biogeography of Australia, significant uncertainties remain concerning the temporal biogeographical changes closely related to the timing of Permian glacial-interglacial events. Several recent studies along these research lines demonstrate the importance of a reliable high-resolution biostratigraphical timescale for paleobiogeographical and paleoclimatic reconstructions. This paper provides, for the first time, a full taxonomic and biostratigraphical study of the brachiopod fauna from the Wasp Head Formation, southern Sydney Basin, southeastern Australia. The fauna is associated with deposits of the first Permian glacial interval suggested for eastern Australia. Three brachiopod assemblages are recognized. The lower and middle assemblages contain scarce brachiopods although associated bivalves are comparatively more common. Despite very low diversity and low abundance, these two brachiopod assemblages contain characteristic species of the Strophalosia concentrica and Strophalosia subcircularis brachiopod zones, both considered of late Asselian age. The third assemblage, occurring in the uppermost part of the formation, contains more brachiopods than bivalves and is referred to early Sakmarian in age. The species diversity and stratigraphic occurrences of the brachiopod assemblages in relation to sedimentary facies suggest that the lower two assemblages may represent an intra-glacial interval while the younger third assemblage, characterized by abundant occurrences of Trigonotreta and Tomiopsis species, accompanied by the bivalve Eurydesma, is more indicative of a post-glacial benthic marine fauna comparable to coeval brachiopod faunas found elsewhere in Gondwana. © 2014, The Paleontological Society.

Proliferation of MISS-related microbial mats following the end-Permian mass extinction in the northern Paleo-Tethys: evidence from southern Qilianshan region, western China

As a consequence of the end-Permian mass extinction, microbes proliferated in the post-extinction shallow marine ecosystems, in which they grew as various microbially induced sedimentary structures (MISSs) in siliciclastic settings. This paper reports, for the first time, the discovery of abundant MISSs from the lowest Triassic sandstones of shallow-water margin origin in the Zhihema sections of the southern Qilianshan region, West China. The sandstones are characterized by well-developed cross-beddings and ripple marks, and a Claraia-dominated bivalve assemblage of middle-late Griesbachian age. These sedimentary structures, together with the bivalves, suggest a high-energy peritidal zone of a shoreface setting in a clastic shallow sea environment. Seven types of MISSs are recognized and described here: pictograph-like sand cracks/crack-fills, polygonal sand crack-fills, erosional remnants, multidirectional linear grooves, sinuous crack-fills, fusiform sand cracks/crack-fills, and leveled ripple marks. Most of the newly found MISSs are morphologically comparable with their ancient and modern counterparts. Detailed optical microscope and scanning electron microscope (SEM) analyses reveal that thin clayey laminae and filamentous mica grains are aligned parallel to bedding plane, and that the matrix-supported quartz grains, overall, are oriented; both of which are interpreted to indicate biogenic origin. The biogenic origin of these MISSs is reinforced by the presence of copious putative nanoglobules and filamentous biofilm-like organic objects in the interspaces of clay minerals in laminated layers. These nanometer-scale objects are interpreted as bacterial bodies or remains that have been replaced with inorganic minerals upon fossilization. The presence of MISSs on the northern margins of Paleo-Tethys indicates that the post-extinction microbial mats had expanded their distributions from low-latitude to moderate-high latitude regions. Moreover, unlike some previously reported microbial mats that contain very rare body and trace fossils, the southern Qilianshan MISSs were found in association with abundant vertical burrows and bivalves, suggesting that the MISS-forming microbial mats may have served as oases for trace-making organisms and opportunistic bivalves to flourish in shallow-marine habitats immediately after the end-Permian mass extinction.