Unexpected diversity of ratites (Aves,Palaeognathae) in the early Cenozoic of South America: palaeobiogeographical implications

Agnolin, F.L., July 2016. Unexpected diversity of ratites (Aves, Palaeognathae) in the early Cenozoic of South America: palaeobiogeographical implications. Alcheringa 41, xxx–xxx. ISSN 0311-5518.

Ratitae is represented in South America exclusively by Rheidae. Recently, the oldest purported fossil rheid, Diogenornis fragilis, was attributed by several authors to various other ratite clades. A new revision of museum fossil specimens from Argentina has resulted in the discovery of several ratite specimens that clearly do not belong to Rheidae, but resemble other clades. The newly identified specimens derive from Paleogene and Miocene strata. The great diversity of non-rheid Patagonian ratites ended via extinction of several groups by the late Miocene, probably owing to enhanced aridity that also favoured the dispersal of arid-adapted rheids. The new specimens described here reinforce the hypothesis that the traditional vicariant biogeographical model, which proposes ratite clades originated exclusively before the breakup of the Gondwana supercontinent, is questionable owing to the unexpected diversity of various ratite clades in South America, and also in Europe and Africa. This might indicate that the history of Ratitae was more complex than previously envisioned.

Federico L. Agnolin* [fedeagnolin@yahoo.com.ar], Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’, Av. Ángel Gallardo, 470 (1405), Buenos Aires, Argentina. *Also affiliated with: Fundación de Historia Natural ‘Félix de Azara’, Departamento de Ciencias Naturales y Antropología, Universidad Maimónides, Hidalgo 775 (C1405BDB) Ciudad Autónoma de Buenos Aires, República Argentina.     

Early Permian Foraminifera from Eastern Himalaya and their palaeobiogeographic significance

Foraminiferal assemblage from Permian rocks of Eastern Himalaya, India are recorded for the first time. Twenty-two genera and twenty-eight species are documented from the Garu Formation, Eastern Himalaya. The foraminiferal assemblage supports previous age determinations based on megafauna. The distinctive foraminiferal assemblage from India supports the recognition of Australian and Afghanistan-Indian provinces in the Early Permian Austral realm. An appreciable number of common species in these provinces is indicative of close geographic links.     

A new Ordovician rostroconch mollusc from Kazakhstan

The rostroconch mollusc Eopteria aiteneria sp. nov. is described from the Late Ordovician Angrensor Formation of north-eastern Central Kazakhstan; it is the first and only known representative of this group from the Ordovician of central Asia. By the beginning of the Late Ordovician Eopteria and the family Eopteriidae were on the verge of extinction and the new Kazakhstan species represents the youngest preserved record of the family in the Ordovician. It is likely that the group found a refuge in the diverse, but rather conservative, faunal assemblage of the Hiberno-Salairian type associated with Late Ordovician carbonate algal build-ups and mud mounds which spread widely during the late Caradoc to mid Ashgill across Kazakhstanian volcanic island arcs and microplates.     

Australian Cainozoic Bryozoa, 1: Nudicella gen. nov. (Onychocellidae,Cheilostomata): taxonomy,palaeoenvironments and biogeography

The new bryozoan genus Nudicella (Onychocellidae, Cheilostomata) is proposed to accommodate the common and widespread Australian Cainozoic cheilostome bryozoan Eschara clarkei Tenison Woods, which is redescribed and subdivided into four species: N. clarkei (Tenison Woods), N. cribriforma sp. nov., N. latiramosa sp. nov. and N. tenuis sp. nov. Cellaria gigantea Maplestone is also reassigned to Nudicella. Colonies of this genus display a wide variety of growth forms, including cribrate fenestrate, flat robust branching, foliose, delicate branching and encrusting; their occurrences correlate with changes in sedimentary facies and palaeoenvironments. The distinctive cribrate style of fenestrate growth form has evolved convergently in unrelated bryozoan groups at various geological intervals. It is found in a wide variety of sedimentary facies, as in other coexisting opportunistic genera such as Celleporaria, indicating a wide ecological tolerance. The oldest recorded occurrence of Nudicella is in the Paleocene of north western Australia. From there it appears to spread south in the Eocene and then east towards the Otway Basin in southeastern Australia, where it occurs in the Oligocene and Miocene; no post-Miocene representatives of this genus are yet known.     

Relationships of tristichopterids (osteolepiform lobe-finned fishes) from the Middle–Late Devonian of East Gondwana

Wang, Z-B., Gao, J-H., Wang, G-H. &; Kang, Z-H., June 2018.2018. Foraminiferal biostratigraphy and facies analysis of the Permian Longge Formation in the Rongma Area, Tibet, China: implications for the palaeogeography of the South Qiangtang Block. Alcheringa XX, x–x.

The Permian Longge Formation in the South Qiangtang Block, Tibet, is overwhelmingly composed of carbonate rocks with various skeletal (brachiopods, foraminifers, gastropods, echinoderms, ostracods, corals, bivalves, algae, and bryozoans) and non-skeletal (intraclasts and ooids) components. Three stratigraphic sections of the Longge Formation in the Rongma area of north-central Tibet—known as South Yibug Caka, Niushan and East Yibug Caka—were selected for this study, which examined both sedimentary facies and foraminiferal assemblages. The foraminifers in these sections consist of at least 38 species belonging to 18 genera. Based on the distribution of the foraminifers throughout the composite section, two foraminiferal assemblages were established, and the age of the Longge Formation was determined to be late Kungurian to Capitanian. During lithological studies, ten microfacies were identified using depositional textures, petrographic analysis and faunal content: mudstone, bioclast wackestone, bioclast perforated-foraminifera packstone, bioclast crinoid grainstone, intraclast wackestone, breccia, intraclast grainstone, ooid grainstone, fine crystalline dolostone and residual-grain dolostone. These microfacies are interpreted to represent four depositional environments—restricted lagoon, open marine, shoal and slope—which together suggest a shoal-rimmed carbonate platform. The non-fusuline foraminifers show transitional palaeobiogeographic affinities (Tethyan Cimmerian subregion), and the assemblage is considered to be influenced by the northward drift of the South Qiangtang Block, the climatic warming after the Late Paleozoic Ice Age and warm-water oceanic currents caused by the newly formed Neotethys Ocean. This indicates that the South Qiangtang Block was located in a relatively warm-water, low-latitude area during the middle Permian. The Permian depositional sequences in the Rongma area were also influenced by the palaeogeographic evolution of the South Qiangtang Block.

Zhong-Bao Wang [zbwang@cugb.edu.cn] and Zhi-Hong Kang [kangzh98@cugb.edu.cn] School of Energy Resource, China University of Geosciences (Beijing), 29 Xueyuan Road, Beijing 100083, PR China; Jin-Han Gao* [wang_zhongbao@126.com] and Gen-Hou Wang [wgh@cugb.edu.cn] School of Earth Sciences and Resources, China University of Geosciences (Beijing), 29 Xueyuan Road, Beijing 100083, PR China.     

A Devonian fish fauna from subsurface sediments in the eastern Officer Basin,South Australia

This paper reports the discovery of three of the most iconic New Caledonian endemic genera, Amphorogyne, Paracryphia and Phelline, as dispersed leaf cuticle fossils in the early Miocene of New Zealand. New Caledonia's endemic angiosperm families have given it a reputation as one of the most interesting botanical regions in the world, but unfortunately it has no known pre-Pleistocene Cenozoic plant fossil record. A once more widespread distribution of its key plants in the context of a cooling and drying Neogene world suggests the current vegetation of New Caledonia is the result of contraction, or even a migration, from more southerly landmasses. Thus, New Zealand may have been a source of at least some of New Caledonia's plants.     

Late quaternary Palorchestes azael (Mammalia,Diprotodontidae) from northwestern Tasmania

A fossil mandible and incisor of the diprotodontid marsupial Palorchestes azeal Owen is reported from a new locality at Pulbeena, near Smithon, in northwestern Tasmania. The fossils occurred with a piece of wood which has a ¹⁴C age of 54,200_-4,500 ^+11,000 B.P. Both fossils and wood were deposited contemporaneously in shallow-lake shell marls and swamp peat deposits of late Quaternary age. Pollen analysis indicates that this P. azael inhabited a Eucalyptus woodland.     

Prehistoric Molluscan Faunas of the Yazoo River,Mississippi, USA: Archaeological Perspectives for Modern Conservation

Archaeological faunal assemblages can provide data valuable to modern conservation ecology. For example, while freshwater mussels (Bivalvia: Unionidae, Margaritiferidae) are common constituents in the archaeological record of North America, today they are one of the world’s most imperiled faunal groups. Efforts to aid habitat restoration, population growth, and species reintroduction can be informed by studies of prehistoric mussel assemblages. These data can provide a historical perspective, cataloging communities as they existed prior to extensive modern impacts, thus representing an ecological baseline to be compared with modern populations. This study focuses on two late prehistoric (ca. 300–600 AD) sites on the Yazoo River, where nearly 24,000 freshwater mussel valves were recovered. Though modern data are extremely limited for the river, analysis revealed it once supported a diverse mussel community containing numerous species currently considered rare, endangered, or extinct in Mississippi. In total, the combined shell assemblages yielded 23 new river records for the Yazoo River. One species in particular, Quadrula fragosa, represents the second such occurrence in Mississippi, and bolsters its candidate status as a new state record, as argued in a recent report from a neighbouring river in the Yazoo Basin.     

The Archaeological Record of Human Impacts on Animal Populations

Recent archaeological research has fundamentally altered our understanding of the scope of past human impacts on nondomesticated animal populations. Predictions derived from foraging theory concerning the abundance histories of high-return human prey and diet breadth have been met in many parts of the world. People are known to have introduced a broad variety of nondomesticated animals, from sponges to agoutis and rats, to a remarkably broad set of contexts, in turn causing a wide variety of secondary impacts. By increasing the incidence of fire, human colonists have in some cases transformed the nature of the vegetation on the colonized landscape, in turn dramatically affecting animal populations on those landscapes. In island settings, these triple threats--predation, biotic introductions, and vegetation alteration--routinely led to extinctions but there is no archaeological evidence that small-scale societies caused extinction by predation alone on islands or continents. Indeed, the recent history of this famous argument suggests that it is better seen as a statement of faith about the past rather than as an appeal to reason. Perhaps most importantly, our burgeoning knowledge of past human impacts on animals has important implications for the conservation biology of the future.     

A new Late Famennian lungfish from New South Wales,Australia, and its bearing on Australian-Asian terrane relations

A new genus and species of lungfish with toothplates, Adelargo schultzei, is described from the Hunter Siltstone (Devonian, Late Famennian) near Grenfell, New South Wales. Materials assigned to Adelargo schultzei gen. et sp. nov., include a portion of the left side of the skull comprising B, I (postparietal) and J (parietal) bones, pterygoid and prearticular toothplates, a parasphenoid with a long posterior stalk, vertebrae, ribs, anal fin supports and scales. Toothplates are similar to Dipterus, although morphology of the skull, parasphenoid and postcranial elements is more derived. Biogeographic relationships of the Grenfell fauna were based on the presence of the antiarch group Sinolepidoidei, also present on Asian terranes during the Late Devonian. A small number of lungfish scales have been described from Asian sinolepid localities of this age, but differ from those of Adelargo schultzei, and other faunal similarities between these areas appear limited. Paucity of eastern Australian Devonian taxa on the North and South China blocks implies that strong biogeographic relationships between eastern Australia and Euramerican localities during the Late Devonian were not the result of Asian migration routes, but the closer proximity of these areas.