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The Australian Museum has a large palaeontological collection of Triassic specimens from the Sydney Basin, including many type specimens. This study reviewed every presently described Sydney Basin Hawkesbury Sandstone plant and animal taxon that has representative specimens held in the Australian Museum. Fifty-two taxa are included from numerous sites. These include three amphibians, twenty-eight fishes, eleven insects, one horseshoe “crab”, one scorpion, three crustaceans, two molluscs and three plants. Basic taxonomic history is noted, together with specimen registration numbers and their position in the collection. Also included are references to relevant specimens held in the Geological Survey of New South Wales and the Natural History Museum, London collections. Images of every taxon are included. To place the collection in context, particularly for educators working with students, brief descriptions of the geology that forms the Hawkesbury Sandstone, and the inferred ecosystems that existed during the Middle Triassic, are included. The results of this study will help to facilitate further researchers by providing important details of the fossil collections held at the Australian Museum.

This list updates the fossil fish types deposited in the collections of the University of Alberta Laboratory for Vertebrate Palaeontology (UALVP). This collection contains 111 fish holotypes, 1073 fish paratypes, 62 casts of fish holotypes from other museums, and 31 casts of fish paratypes from other museums. The catalogue number, the latest classification, a short description of the material, the collector(s) of the holotype (if known), the type locality, the full citation including the pages on which it was described, tables, and listings of any figures are provided for each type specimen. As in Bruner's (2019) list, this includes unpublished “types” languishing in Ph.D. and M.Sc. theses, as these specimens are labeled in the collections as “types” on the museum labels and in the computer catalogue. Also, this type catalogue lists specimens incorrectly cited as holotypes and paratypes in the scientific literature, mistakes made in Bruner's (2019) listing, and type specimens on long term loan to the UALVP (Paleontology Collections (PAL) of the Institut Teknologi Bandung (ITB)).

The La Cantera Formation (Aptian) represents an underfilled lake system developed in an extensional basin during the Cretaceous hothouse and it bears an abundant and diverse fossil record. Our goal was to investigate paleoclimate conditions of the unit from a multiproxy approach. We analyzed two proxies: a) the stable isotope (carbon and oxygen) composition of basal Actinopterygii and Neopterygii fish remains and from indeterminate plant remains; and b) the clay mineral assemblage composition; providing two independent lines of evidence to reconstruct paleoclimate conditions including paleotemperature calculations for lake waters. The values obtained for fish remains for δ13C range between -8.4 and -1.3 ‰ (δ13C= χ -5.57‰; σ ± 2.25); and δ18O values that vary between -5.7 and -3.6‰ (δ18O= χ -4.33‰; σ ± 0.84); in the case of plant remains δ13C values range between -25.8 and -22.8‰ (δ13C= χ -25‰ -4.33). Paleotemperatures obtained from δ18O for the water column ranged between 23.33 to 35.80 °C. Plant δ13C signature allowed obtaining a δ13CCO2 composition of -5 ‰. This agrees with the interpretation of the La Cantera originating from sediment deposition in an underfilled lake basin and with the global climate context of the Cretaceous. The clay mineral assemblage is dominated by illite-smectite indicating enhanced hydrolysis and seasonal rainfall supporting temporal warmup of the lake. Our data supports aridity conditions during the La Cantera paleolake existence. These findings suggest that geochemical proxies of paleontological datasets are accurate for paleoclimate reconstructions for the deep time records of the La Cantera lacustrine system.

Until now it was believed that the discovery of the Early Cretaceous fossil fish of the Santana Formation, Araripe Plateu, Cearà, Brazil, dated back to the period between 1817 and 1820, when the two Austrian naturalists Johann Baptist von Spix and Carl Friedrich Philipp von Martius made an exploratory journey in Brazil. New documents show, however, that it was the German naturalist, naturalized Dutch, Maria Sibylla Merian (1647-1717) who came into possession of at least one specimen of fossil fish from the Araripe Plateau, during her exploratory journeys made in Suriname between 1669 and 1701. Merian inserted an unequivocal drawing of this fish (probably a specimen of Rhacolepis buccalis, insided in a typical concretion nodule from the Santana Formation) in Plate LIX of the book by Jorg Eberhardt Rumph (1628-1702) entitled "D'Amboinsche Rariteitkamer, etc.", which was published posthumously (1705) and which Merian was commissioned to illustrate. The pre-dating of this important scientific event places the discovery of the fossil fish of the Early Cretaceous of Cearà among the first discoveries of fossil fish that took place on a global level, reinforcing the importance of this locality also under a historical point of view. [ABSTRACT FROM AUTHOR]

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Thirty-eight otolith-based species of fishes and 41 foraminifera species have been recorded in the Borský Mikuláš-Vinohrádky section in the upper Badenian deposits in the eastern part of the Vienna Basin, in West Slovakia. Two new species of otoliths are introduced here: Thorogobius antirostratus n. sp. and Gerres mlynskyi n. sp. Among the foraminifera Biasterigerina planorbis and Elphidium crispum associated with other elphidiids, Lobatula lobatula and Cibicides crassiseptatum prevail. Overall, the family of Gobiidae dominate in the assemblage of otoliths (>90 % of specimens). Meso- and epipelagial fishes or diversified gadids and sciaenids are missing. From the molluscs, the first record of Aturia sp. in the Borský Mikuláš section is observed. Otoliths and foraminifera document a normal marine environment of well-aerated shallow water with a depth of 30-50 metres, with muddy to sandy bottoms of marine meadows and plenty of light in the subtropical climatic conditions. Several fish genera (for example Gerres) give evidence for the nearness of reef structures. There are no species (excepting Lesueurigobius vicinalis) in common with the known Lower Serravallian otolith fauna from the Eastern Paratethys. Some species from the Borský Mikuláš-Vinohrádky section can also be found in the Mediterranean Langhian-Serravallian interval and are interpreted as a relic of the lower Badenian (Langhian) fish assemblages. [ABSTRACT FROM AUTHOR]

Thirty-eight otolith-based species of fishes and 41 foraminifera species have been recorded in the Borský Mikuláš-Vinohrádky section in the upper Badenian deposits in the eastern part of the Vienna Basin, in West Slovakia. Two new species of otoliths are introduced here: Thorogobius antirostratus n. sp. and Gerres mlynskyi n. sp. Among the foraminifera Biasterigerina planorbis and Elphidium crispum associated with other elphidiids, Lobatula lobatula and Cibicides crassiseptatum prevail. Overall, the family of Gobiidae dominate in the assemblage of otoliths (>90 % of specimens). Meso- and epipelagial fishes or diversified gadids and sciaenids are missing. From the molluscs, the first record of Aturia sp. in the Borský Mikuláš section is observed. Otoliths and foraminifera document a normal marine environment of well-aerated shallow water with a depth of 30-50 metres, with muddy to sandy bottoms of marine meadows and plenty of light in the subtropical climatic conditions. Several fish genera (for example Gerres) give evidence for the nearness of reef structures. There are no species (excepting Lesueurigobius vicinalis) in common with the known Lower Serravallian otolith fauna from the Eastern Paratethys. Some species from the Borský Mikuláš-Vinohrádky section can also be found in the Mediterranean Langhian-Serravallian interval and are interpreted as a relic of the lower Badenian (Langhian) fish assemblages.

The Redbank Plains Formation, between Brisbane and Ipswich in South East Queensland, provides fossil evidence of the fauna and flora of the earliest part of the Cenozoic era, and is dated from the Paleogene Period, specifically the late Paleocene--early Eocene (66--55 Ma). These fossils have been collected and studied for over 120 years, but the conjunction of agriculture in the then-rural Redbank Plains district, and the mapping of the valuable Ipswich coalfields, led to their palaeontological significance being recognised and documented. Scientific study began in 1916 and has continued since, revealing some of the earliest evidence of modern Australian fauna and flora. However, the area's rich underground coal resources and a hunger for residential land in a rapidly developing urban corridor, has resulted in the loss of or threats to the fossil sites. One deposit has been given local government status as a Conservation Park and remains accessible for scientific study, but the lack of either national or state protection for such significant sites in Queensland and Australia imperils our national geological heritage and its scientific contribution. [ABSTRACT FROM AUTHOR]

Shark teeth discovered in the late Paleocene-early Eocene Chehel-Kaman Formation in NE Iran bring new data on the fossil fish record from this country. Two genera from the location are described and figured. The present record is one of the very few reports of fossil shark teeth from the Cenozoic of Iran and the first one from this formation and region. The marine vertebrates known from this region of the Tethys Sea are very scarce.

Two species of fossil cichlid are described from Oligocene deposits of Libya. One is formally described as Libyachromis fugacior gen. et sp. nov. This species is considered to be the sister group to most of the remaining members of the African subfamily Pseudocrenilabrinae, perhaps close to Heterochromis, and is characterized by two predorsal bones, dorsal fin with 12–14 spines and 9–12 rays, 24–28 vertebrae, cycloid scales present on body and head including cheek, and only unicuspid teeth present on the oral and pharyngeal jaws. The second fossil form is less complete, and so we do not formally name it, but it appears to be most closely related to Tylochromis, and thus we place it in the Tylochromini. These new fossils increase our understanding of the diversity of cichlid lineages in the Palaeogene. The unnamed fossil supports the presence of Tylochromini in the Eocene and Oligocene of North Africa, as was previously suggested by the remains of partial lower pharyngeal jaws from Egypt and Libya. The named fossil adds to the known diversity of early Cenozoic cichlids that document the presence of probably Heterochromini along with Tylochromini in North Africa. [ABSTRACT FROM AUTHOR]

Ray-finned fishes (Actinopterygii) comprise nearly half of all modern vertebrate diversity, and are an ecologically and numerically dominant megafauna in most aquatic environments. Crown teleost fishes diversified relatively recently, during the Late Cretaceous and early Paleogene, although the exact timing and cause of their radiation and rise to ecological dominance is poorly constrained. Here we use microfossil teeth and shark dermal scales (ichthyoliths) preserved in deep-sea sediments to study the changes in the pelagic fish community in the latest Cretaceous and early Paleogene. We find that the Cretaceous-Paleogene (K/Pg) extinction event marked a profound change in the structure of ichthyolith communities around the globe: Whereas shark denticles outnumber ray-finned fish teeth in Cretaceous deep-sea sediments around the world, there is a dramatic increase in the proportion of ray-finned fish teeth to shark denticles in the Paleocene. There is also an increase in size and numerical abundance of ray-finned fish teeth at the boundary. These changes are sustained through at least the first 24 million years of the Cenozoic. This new fish community structure began at the K/Pg mass extinction, suggesting the extinction event played an important role in initiating the modern "age of fishes."

A compressed fossil fish bearing close resemblance to sub-family Leuciscinae (family: Cyprinidae) is reported from latest Neogene (?Pliocene) sediments of Chotanagpur plateau, eastern India. The recovered fossil fish contains exceptionally well-preserved skeleton. It is characterized by compressed belly, medium-sized head, well-preserved skull, ten caudal vertebrae, moderately long vertebral spines, cycloid scales, and well-preserved dorsal, pectoral, pelvic, anal and caudal fins. The fossil material and associated angiospermic flora indicate the existence of Leuciscinae and freshwater lacustrine environment (with intermittent fluvial incursions during flood events) in the Chotanagpur plateau during the depositional period. [ABSTRACT FROM AUTHOR]

The new genus Thiollierepycnodus is erected here to accommodate ' Gyrodus ' wagneri or ' Proscinetes ' wagneri , a taxon known since the 19th century from the marine Kimmeridgian Plattenkalk of Cerin (France) and since 2014 at the excavation site of the Naturkunde-Museum Bamberg in Wattendorf (Germany). Thiollierepycnodus is placed in Pycnodontidae (Upper Jurassic to Eocene), which is the most advanced family of Pycnodontiformes. With 154–152 Myr (Upper Jurassic), Thiollierepycnodus belongs to the stratigraphically oldest Pycnodontidae, still possessing some primitive features such as four incisiform teeth in the dentary, a crown of bifurcated anterior dentary teeth, reduced scale bars posterior to the dorsal fin origin, but the area of pterygiophores without scales and nine to 10 postanal ventral keel scales and approximately 10 complete scale rows posterior to the cloaca. A phylogenetic analysis leads to the placement of this taxon in Proscinetinae. This and the introduction of two additional taxa from the Cretaceous of Lebanon in the phylogeny are further steps to enlighten the broader evolutionary patterns of Pycnodontidae. [ABSTRACT FROM AUTHOR]

During the first 70 years of the XX century very few researches have concerned the marine Triassic fishes. They were prevalently related to the many scientific expeditions carried out in the first half of that century in localities situated along the Pangea margins during the Early Triassic: Greenland, Canada, Spitzbergen, Madagascar. My story starts when, still undergraduate, in 1975 I joined Prof. Maurizo Gaetani on a mapping trip in the Belluno Dolomites: there I found my first fossil remain of a Triassic fish. Since then, excavations and field works have followed one another, almost always concerning new fossil- bearing levels, going back very recently to the same spot in Dolomites, Last September, 41 years after my first discovery of a Triassic fossil fish, I had the opportunity of a new survey on Monte Civetta where I found much more than I expected.

A new Mesozoic fossiliferous locality was discovered in the Mae Sot Basin, western Thailand. Ginglymodian fish scales and bones are reported, as well as wood (Brachyoxylon sp.) and leafy twigs (cf. Cupressinocladus sp.). These are associated with Skolithos and Scoyenia ichnofacies. The biotic remains were deposited in an anoxic fluvial environment and wood underwent humification. Fossil wood specimens show a wide range of composition, ranging from nearly pure carbon to mixtures of coal and siliceous sediment. The limited fossil record makes biogeographical comparisons and stratigraphic deductions difficult. It is however the first time that terrestrial Mesozoic biota is reported from the Shan-Thai terrane west of the Chiang Mai suture and north of the Three Pagoda fault. Further research in and around this locality may refine our still fragmentary knowledge of Mesozoic continental ecosystems west of the Nan-Uttaradit suture. [ABSTRACT FROM AUTHOR]

Pycnodontiformes are an extinct order of Actinopterygian fishes, present from the Late Triassic (Norian) to the Eocene. With their mostly deep, laterally compressed bodies and comparatively large fins, these fishes were mostly highly manoeuvrable reef fish. The genus Macromesodon Blake, 1905 (sensu Poyato-Ariza and Wenz, 2004) is divided again in the genus Macromesodon, with Macromesodon macropterus (Agassiz, 1834) as the only species and the genus Apomesodon Poyato-Ariza and Wenz, 2002.

Recent pike-like predatory fishes attack prey animals by a quick strike out of rest or slow movement. This fast-start behaviour includes a preparatory, a propulsive and a final phase, and the latter is crucial for the success of the attack. To prevent prey from escape, predators tend to minimise the duration of the interaction and the disturbance caused to surrounding water in order to not be detected by the prey's lateral line sensory system. We compared the hydrodynamic properties of the earliest fossil representative of the pike-like morphotype, the Triassic actinopterygian Saurichthys, with several recent pike-like predators by means of computational fluid dynamics (CFD). Rainbow trout has been used as a control example of a fish with a generalist body shape. Our results show that flow disturbance produced by Saurichthys was low and similar to that of the recent forms Belone and Lepisosteus, thus indicative of an effective ambush predator. Drag coefficients are low for all these fishes, but also for trout, which is a good swimmer over longer distances but generates considerable disturbance of flow. Second-highest flow disturbance values are calculated for Esox, which compensates the large disturbance with its extremely high acceleration performance (i.e. attacks at high speeds) and the derived teleostean protrusible mouth that allows prey catching from longer distances compared to the other fishes. We show CFD modelling to be a useful tool for palaeobiological reconstruction of fossil fishes, as it allows quantification of impacts of body morphology on a hypothesised lifestyle.

The Upper Mississippian Bluefield Formation of the Mauch Chunk Group in southeastern West Virginia is known for its preservation of a variety of invertebrate taxa and early tetrapod trackways, but no lower actinopterygian remains have been formally described from these Carboniferous rocks. Here, the first lower actinopterygian fish is described from the Bluefield Formation of West Virginia. This fish is represented by a nearly complete articulated specimen with a three-dimensional snout and an unobstructed view of the gular and branchiostegal region. This new taxon is defined by a unique set of characters, which include features of the snout, circumorbital series, cheek, and operculo-gular region. These features make this fish different and distinct from previously described Carboniferous fishes. Some of the morphological features of note include the presence of a distinct lacrimal, premaxillary, ventral rostral and dorsal rostral bones, a narrow infraorbital ventral to the orbit, and a large crescent shaped infraorbital that contacts a single dermosphenotic. There is an anteriorly inclined hatchet-shaped preoperculum and six small suborbital bones anterior to the expanded region of this bone that filling the space between the preoperculum, dermosphenotic, and infraorbital. Posterior to the preoperculum, there is a single wedge-shaped dermohyal and a series of three rectangular anteopercular bones. The anteopercular bones extend halfway down the anterior border of the rectangular operculum. A median gular, two pairs of lateral gulars, and at least eight branchiostegal rays are present. The heterocercal caudal fin is deeply cleft and inequilobate. The scales have pectinated posterior margins and bear diagonal ridges of ganoine. The description of this new taxon represents the first actinopterygian and the first vertebrate body fossil described from the Bluefield Formation and the second actinopterygian taxon described from the Mauch Chunk Group in West Virginia.

The Upper Mississippian Bluefield Formation of the Mauch Chunk Group in southeastern West Virginia is known for its preservation of a variety of invertebrate taxa and early tetrapod trackways, but no lower actinopterygian remains have been formally described from these Carboniferous rocks. Here, the first lower actinopterygian fish is described from the Bluefield Formation of West Virginia. This fish is represented by a nearly complete articulated specimen with a three-dimensional snout and an unobstructed view of the gular and branchiostegal region. This new taxon is defined by a unique set of characters, which include features of the snout, circumorbital series, cheek, and operculo-gular region. These features make this fish different and distinct from previously described Carboniferous fishes. Some of the morphological features of note include the presence of a distinct lacrimal, premaxillary, ventral rostral and dorsal rostral bones, a narrow infraorbital ventral to the orbit, and a large crescent shaped infraorbital that contacts a single dermosphenotic. There is an anteriorly inclined hatchet-shaped preoperculum and six small suborbital bones anterior to the expanded region of this bone that filling the space between the preoperculum, dermosphenotic, and infraorbital. Posterior to the preoperculum, there is a single wedge-shaped dermohyal and a series of three rectangular anteopercular bones. The anteopercular bones extend halfway down the anterior border of the rectangular operculum. A median gular, two pairs of lateral gulars, and at least eight branchiostegal rays are present. The heterocercal caudal fin is deeply cleft and inequilobate. The scales have pectinated posterior margins and bear diagonal ridges of ganoine. The description of this new taxon represents the first actinopterygian and the first vertebrate body fossil described from the Bluefield Formation and the second actinopterygian taxon described from the Mauch Chunk Group in West Virginia. [ABSTRACT FROM AUTHOR]

in past ana present ecosystems, tropnic interactions determine material ana energy transiers among species, regulating population dynamics and community stability. Food web studies in past ecosystems are helpful to assess the persistence of ecosystem structure throughout geological times and to explore the existence of general principles of food web assembly. We determined and compared the trophic structure of two Devonian fish assemblages [(1) the Escuminac assemblage (ca. 380 Ma). Miguasha. eastern Canada and (2) the Lode assemblage (ca. 390 Ma), Straupe. Latvia] with a closer look at the Escuminac assemblage. Both localities are representative of Middle to Late Devonian aquatic vertebrate assemblages in terms of taxonomic richness (ca. 20 species), phylogenetic diversity (all major groups of lower vertebrates) and palaeoenvironment (palaeoestuaries). Fossil food web structures were assessed using different kinds of direct (i.e. digestive contents and bite marks in fossils) and indirect (e.g. ecomorphological measurements, stratigraphic species co-occurrences) indicators. First, the relationships between predator and prey body size established for the Escuminac fishes are comparable to those of recent aquatic ecosystems, highlighting a consistency of aquatic food web structure across geological time. Second, non-metric dimensional scaling on ecomorphological variables and cluster analysis showed a common pattern of functional groups for both fish assemblages; top predators, predators, primary and secondary consumers were identified. We conclude that Devonian communities were organized in multiple trophic levels and that size-based feeding interactions were established early in vertebrate history. [ABSTRACT FROM AUTHOR]

A new osteichthyan fauna from the lower Campanian Aguja Formation of West Texas represents a critical southern datum regarding the interpretation of faunal differences observed among Upper Cretaceous, non-marine fish assemblages of the Western Interior. Bony fish are represented within the "Lowerverse" local fauna by as many as 21 primitive and advanced species. The Lowerverse locality is situated at the southern end of a geographic range of paracontemporaneous localities in Laramidia that have produced a number of similarly well-sampled osteichthyan assemblages. A comparison of the Lowerverse bony fish fauna with those of southern Utah and southern Alberta supports previous hypotheses regarding the latitudinal segregation of some species in the Western Interior. Given their ubiquity throughout Late Cretaceous North America in both time and space, the north-south geographical segregation of garfishes in the Western Interior is especially revealing in this regard and reveals that some species were markedly provincial during the Campanian. Taxonomic inconsistencies among these regional faunas are observed even at higher taxonomic ranks and infer that such differences are sending meaningful ecological signals. [ABSTRACT FROM AUTHOR]

Ray-finned fishes (Actinopterygii) comprise nearly half of all modern vertebrate diversity, and are an ecologically and numerically dominant megafauna in most aquatic environments. Crown teleost fishes diversified relatively recently, during the Late Cretaceous and early Paleogene, although the exact timing and cause of their radiation and rise to ecological dominance is poorly constrained. Here we use microfossil teeth and shark dermal scales (ichthyoliths) preserved in deep-sea sediments to study the changes in the pelagic fish community in the latest Cretaceous and early Paleogene. We find that the Cretaceous–Paleogene (K/Pg) extinction event marked a profound change in the structure of ichthyolith communities around the globe: Whereas shark denticles outnumber ray-finned fish teeth in Cretaceous deep-sea sediments around the world, there is a dramatic increase in the proportion of ray-finned fish teeth to shark denticles in the Paleocene. There is also an increase in size and numerical abundance of ray-finned fish teeth at the boundary. These changes are sustained through at least the first 24 million years of the Cenozoic. This new fish community structure began at the K/Pg mass extinction, suggesting the extinction event played an important role in initiating the modern "age of fishes." [ABSTRACT FROM AUTHOR]

The Pirabas Formation of Early Miocene age represents the final stage of the central western Atlantic carbonate platform in northeastern South America, predating the emplacement of the Amazon delta system. The otolith-based fossil fish fauna is represented by 38 species typical of a shallow marine environment. A total of 18 species are described new to science from the families Congridae, Batrachoididae, Bythitidae, Sciaenidae and Paralichthyidae. The fish fauna was associated with high benthic and planktic primary productivity including seagrass meadows, calcareous algae and suspension-feeders. The break of todays shallow marine bioprovince at the Amazonas delta mouth is not evident from the fish fauna of the Pirabas Fm., which shows good correlation with the Gatunian/proto-Caribbean bioprovince known from an only slightly younger time window in Trinidad and Venezuela. Differences observed to those Early Miocene faunal associations are interpreted to be mainly due to stratigraphic and geographic and not environmental differences. We postulate that the emergence of the Amazonas river mouth close to its present day location has terminated the carbonate cycle of the Pirabas Fm. and pushed back northwards a certain proportion of the fish fauna here described. [ABSTRACT FROM AUTHOR]

Abstract: The paleoenvironmental context and diagenetic history of the middle Frasnian Escuminac Formation were investigated through geochemical (rare earth elements) and isotopic (Rb–Sr, Nd–Sm) analyses of fossil fish material and sediments. Samples of sediments and bioapatite were collected from the base to the top of the Escuminac Formation. Strontium isotope ratios (87Sr/86Sr) for bioapatites vary from 0.70804 to 0.70845 and overlap with Frasnian seawater Sr isotope compositions, though most of the biogenic apatites analyzed show a variable drift from marine values toward a more radiogenic continental signature. This trend is possibly the result of post-mortem Sr exchange between fossils and a fluid isotopically distinct from the waters in which they developed. All bioapatites are heavily enriched in rare earth elements (REE) and display a shale-normalized pattern that shows heavy-REE (HREE) depletion and a slight middle-REE (MREE) enrichment. The εNd (t) values of the sediments range from −4.8 to −6.4 and are consistent with a sedimentary provenance derived from an Appalachian source for the Escuminac Formation. In contrast, more radiogenic εNd (t) values (ranging from −2.6 to −4.6) were obtained for the bioapatites. The discrepancy between sediments and fossil material εNd (t) implies the presence of a second, diagenetic, Nd reservoir for the Escuminac bioapatites. We propose that this reservoir reflects, in part, seawater. The similarity between the Nd isotope compositions of the Escuminac fossils and Late Devonian conodonts from Poland argues for a close connection between waters of the Devonian Rheic Ocean and the Escuminac Formation collector basin. [Copyright &y& Elsevier]

The Green River Formation, Wyoming, contains such an abundance of well-preserved flora and fauna that this late early Eocene Lagerstätte is one of the best known from North America. Despite having being studied since the mid-nineteenth century, little is known about the taphonomic processes that resulted in a diverse suite of organisms, especially abundant fossil fish, being preserved in exquisite detail. Two distinct patterns of completeness and articulation recur among the fossil fish: complete and fully articulated, or extensive disarticulation of the anterior part of the fish only ('half and half' preservation). To decipher the processes involved in the preservation of Fossil Lake fish, specimens of the extant taxon Carassius auratus were decayed experimentally over a 6-month period. Various scenarios approximating conditions in the Eocene lake were replicated in the laboratory and each monitored to record the rate of degradation and how different starting conditions impacted on the taphonomy of the fish. Varying salinity or oxygen level did not induce any discernable differences in the pattern of decay; degradation occurred faster at higher temperatures. Unexpectedly, decay rates varied greatly between replicate samples. Soft tissues decomposed rapidly and extensively, and, even in the absence of any disturbance, the skeletal disarticulation that followed was repeatedly much greater than that exhibited by the vast majority of fossil fish from the Green River Formation. The results indicate clearly that decay in a quiet-water environment is, on its own, insufficient to explain the consistently high fidelity preservation of Green River fish: some additional factor is implicated. We propose that microbial mats at the sediment-water interface were key; fish carcasses became adhered to the sediment surface inhibiting floating, disarticulation and loss of bones, with 'half and half' specimens curving laterally and not fully adhering, thus only that part (typically the posterior) in contact with the substrate retained a high degree of skeletal fidelity. [ABSTRACT FROM AUTHOR]

Abstract: A freshwater diatomite deposit near Dunedin, South Island, New Zealand provides an exceptional archive of mid-latitude, seasonal climate variation during latest Oligocene-early Early Miocene time. The diatomite accumulated in a small ~1.5 km diameter maar-floored lake that formed during basaltic volcanism. Except for exposures of basanite dated at 23.2 Ma by 40Ar/39Ar, and remnants of a Paleogene sandstone and conglomerate cover, the diatomite body is surrounded by Otago Schist. Geophysical profiles indicate that the total diatomaceous sediment thickness may exceed 100 m. Two depositional facies are described from 15.5 m of weakly-consolidated fresh diatomite accessible in two pits. A thinly laminated facies, comprising 60% of the section, consists of dark brown and white couplets of average thickness 0.5 mm. Both brown and white laminae are composed essentially of frustules of a single pennate diatom, along with 1–2% of siliceous sponge spicules. Dark laminae also contain abundant 5–7.5 µm diameter siliceous chrysophycean stomatocysts and organic matter. Decalcified complete skeletons of Galaxias, a southern hemisphere group of freshwater or diadromous fish, are found throughout. Diverse well-preserved leaves, some with attached scale insects, are dominated by Lauraceae. Rare flowers are also present. Trace fossils preserved in the laminated comprise 1–1.5 mm wide pale diatomaceous strings of probable faecal origin, and isolated 20–40 mm diameter sand lenses interpreted as faecal remains of swimming waterfowl. The second diatomite facies group comprises dark brown speckled beds, interpreted as sediment gravity flows. Up to 14 cm thick and interspersed throughout the study section, they incorporate abundant laminated diatomite flecks and leaves, and minor woody plant matter and terrigenous silt. Almost all are capped by 1–8 mm of white diatomite that is interpreted as post-flow fall-out of resuspended diatom frustules. Associated breccia and swirly beds up to 8 cm thick are composed of variably contorted clasts of laminated diatomite in a speckled matrix. Nodules, spheroids, and films of authigenic framboidal pyrite are commonly associated with plant and fish remains. As in modern lakes, white laminae likely formed from diatom blooms when light flux, temperature, or nutrients were optimal during spring–early summer; dark laminae accumulating during autumn–winter months. Laterally continuous pinstripe lamination, absence of bioturbation, and excellent fish and plant preservation indicate that the profundal lake and floor were anoxic. Periodic variations in couplet thickness of ~3–10 years compare with Quaternary records of El Niño–Southern Oscillation variability and indicate that the early Early Miocene low altitude New Zealand climate was seasonal and strongly ocean-influenced, as it is today. [Copyright &y& Elsevier]

The paper presents information about the first find of Trachinus minutus (Jonet, 1958) in the Šitbořice Beds (Middle Oligocene) in the Czech Republic. The exemplar is relatively well ossified, however the total length is only 16.5mm. A comparison of preserved morphologic and meristic characters with features in exemplars from other Europian localities shows its similarity to the specimens from Poland. Slightly different praeoperculare morphology is probably caused by ontogeny. The taphonomic information is combined with information about finds of terrestrial elements in Menilitic shale and selected bathymetric and paleoecological data are discussed as possible evidences of coastal upwelling. [ABSTRACT FROM AUTHOR]

Abstract: Thousands of vertebrate fossils have been recovered from the lower Omo River Valley, in southern Ethiopia, however, fishes have been poorly reported. Here we describe fossil fish remains deriving from the Shungura Formation, part of the Omo Group of deposits ranging in date from 1.8 to 3.4 my. Two new species are reported, Sindacharax omoensis (Characiformes) and Lates arambourgi (Perciformes), which suggest greater diversity of these genera than previously documented. [Copyright &y& Elsevier]

A taxonomic revision of mackerel-like fishes (Scombridae, Scombroidei, Perciformes) from the Monte Bolca localities in Italy is presented as part of continuing research into phylogenetic relationships of fossil and Recent scombroids. Three new genera are proposed: † Godsilia, † Pseudauxides and † Thunnoscomberoides. In addition, species generally known as † Thynnus bolcensis, † Thynnus lanceolatus, † Scombrosarda propterygia, † Scomberomorus speciosus and † Scomberomorus tenuis are renamed † Thunnoscomberoides bolcensis comb. nov., † Godsilia lanceolata comb. nov., † Auxides propterygius comb. nov. and † Pseudauxides speciosus comb. nov., respectively. † S. tenuis, a nomen nudum, is a junior synonym of † P. speciosus. Provisional phylogenetic hypotheses of these Monte Bolca scombrids are as follows. † Auxides and † Pseudauxides are most likely primitive sister taxa of the mackerels Scomber and Rastrelliger with † Pseudauxides as the most primitive. † Godsilia may be placed between Scombrinae and Scomberomorinae. † Thunnoscomberoides seems to fit between Scombrinae and Thunnini. [ABSTRACT FROM AUTHOR]

During the last 20 years of paleontological expeditions in different sedimentary basins of Brazil, Colombia, Costa Rica, Ecuador, Jamaica, Trinidad, Panama, the Dominican Republic and Venezuela, teleost otoliths have been found along the tropical western central Atlantic (TWCA) and the tropical eastern central Pacific (TECP); these otoliths relate to the amphi-American distribution of fishes and the paleoceanographic and paleoenvironmental changes in the region during the Cenozoic. This study analyzes of the marine fish fossil based on comprehensive species records belonging to the Neogene period and listed at the generic level. Joint classification and ordination techniques were used to identify and analyze data comprising 169 genera belonging to 56 families and 20 orders, which were mostly represented by the demersal species that inhabit shallow waters. Analyses of principal components were used to calculate the covariance and the variance between formations, countries, basins, and age. The results showed that the main faunistic changes along the geochronological sequence in the Neogene basins of tropical America were a consequence of paleoenvironmental changes. • Review of Teleostean fossil otoliths from tropical America. • Paleobiogeographic analyses of Neogene fish assemblage. • Fish otoliths may be used as geochronoindicators [ABSTRACT FROM AUTHOR]

Fish fossils were recovered from three different depositional contexts at the Pliocene Kanapoi site to: 1) test the assumption that habitat and ecology of modern fish taxa can predict habitat and ecology of fossil taxa; 2) reconstruct the lake and river environments in the Kanapoi Formation, with reference to fish fossils from the nearby Lothagam site deposits; and 3) investigate biogeographical inferences from the fossils. We compare the Kanapoi fish taxa and their depositional environments with the taxa and environments in modern Lake Turkana, and with another Plio-Pleistocene fauna from the eastern Turkana Basin. Taphonomic caveats are discussed. Our results support the use of ecological preferences of modern fish to predict past preferences. Our analysis of the Kanapoi fossils also indicates that the Pliocene Lonyumun Lake had a diverse fauna, with an unusual mix of taxa compared to the modern lake. The presence of possibly endemic species in the Pliocene lake may additionally represent a period of isolation during this epoch. Few fish fossils were recovered in the deposits of the ancestral Kerio River, a primary affluent of Lonyumun Lake then as now, but those present indicate a different ecology than that interpreted for the modern lake. Previously unknown fish taxa which enter the lake during the Pliocene suggest the existence of a connection between the Nile River and the Turkana Basin, which may have been viable for other vertebrates, including hominins., (Copyright © 2018 Elsevier Ltd. All rights reserved.)