scholarly journals VIEWPOINT. Is the Australian subterranean fauna uniquely diverse?

2010 ◽  
Vol 24 (5) ◽  
pp. 407 ◽  
Author(s):  
Michelle T. Guzik ◽  
Andrew D. Austin ◽  
Steven J. B. Cooper ◽  
Mark S. Harvey ◽  
William F. Humphreys ◽  
...  

Australia was historically considered a poor prospect for subterranean fauna but, in reality, the continent holds a great variety of subterranean habitats, with associated faunas, found both in karst and non-karst environments. This paper critically examines the diversity of subterranean fauna in several key regions for the mostly arid western half of Australia. We aimed to document levels of species richness for major taxon groups and examine the degree of uniqueness of the fauna. We also wanted to compare the composition of these ecosystems, and their origins, with other regions of subterranean diversity world-wide. Using information on the number of ‘described’ and ‘known’ invertebrate species (recognised based on morphological and/or molecular data), we predict that the total subterranean fauna for the western half of the continent is 4140 species, of which ~10% is described and 9% is ‘known’ but not yet described. The stygofauna, water beetles, ostracods and copepods have the largest number of described species, while arachnids dominate the described troglofauna. Conversely, copepods, water beetles and isopods are the poorest known groups with less than 20% described species, while hexapods (comprising mostly Collembola, Coleoptera, Blattodea and Hemiptera) are the least known of the troglofauna. Compared with other regions of the world, we consider the Australian subterranean fauna to be unique in its diversity compared with the northern hemisphere for three key reasons: the range and diversity of subterranean habitats is both extensive and novel; direct faunal links to ancient Pangaea and Gondwana are evident, emphasising their early biogeographic history; and Miocene aridification, rather than Pleistocene post-ice age driven diversification events (as is predicted in the northern hemisphere), are likely to have dominated Australia’s subterranean speciation explosion. Finally, we predict that the geologically younger, although more poorly studied, eastern half of the Australian continent is unlikely to be as diverse as the western half, except for stygofauna in porous media. Furthermore, based on similar geology, palaeogeography and tectonic history to that seen in the western parts of Australia, southern Africa, parts of South America and India may also yield similar subterranean biodiversity to that described here.

Insects ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 84
Author(s):  
Wolfgang Paill ◽  
Stephan Koblmüller ◽  
Thomas Friess ◽  
Barbara-Amina Gereben-Krenn ◽  
Christian Mairhuber ◽  
...  

The last ice age considerably influenced distribution patterns of extant species of plants and animals, with some of them now inhabiting disjunct areas in the subarctic/arctic and alpine regions. This arctic-alpine distribution is characteristic for many cold-adapted species with a limited dispersal ability and can be found in many invertebrate taxa, including ground beetles. The ground beetle Pterostichus adstrictus Eschscholtz, 1823 of the subgenus Bothriopterus was previously known to have a holarctic-circumpolar distribution, in Europe reaching its southern borders in Wales and southern Scandinavia. Here, we report the first findings of this species from the Austrian Ötztal Alps, representing also the southernmost edge of its currently known distribution, confirmed by the comparison of morphological characters to other Bothriopterus species and DNA barcoding data. Molecular data revealed a separation of the Austrian and Finish specimens with limited to no gene flow at all. Furthermore, we present the first data on habitat preference and seasonality of P. adstrictus in the Austrian Alps.


2010 ◽  
Vol 124 (3) ◽  
pp. 219
Author(s):  
C. Stuart Houston ◽  
Frank Scott ◽  
Rob B. Tether

Between 1975 and 2002, diminished breeding success of Ospreys was associated with drought and falling lake levels in the western half of our study area near the town of Loon Lake, west-central Saskatchewan. Only 46% of nest attempts were successful in the west compared to 72% in the east, producing 0.88 young per accessible nest in the west and 1.42 in the east. Breeding success was greater in the eastern half, where water levels were stable, in spite of increased human use of the resort lakes there. Our unique long-term Canadian data base results support Ogden's 1977 prediction that Osprey productivity may decrease when water levels drop and fish populations are reduced.


2007 ◽  
Vol 3 (3) ◽  
pp. 323-326 ◽  
Author(s):  
Knud A Jønsson ◽  
Jon Fjeldså ◽  
Per G.P Ericson ◽  
Martin Irestedt

Biogeographic connections between Australia and other continents are still poorly understood although the plate tectonics of the Indo-Pacific region is now well described. Eupetes macrocerus is an enigmatic taxon distributed in a small area on the Malay Peninsula and on Sumatra and Borneo. It has generally been associated with Ptilorrhoa in New Guinea on the other side of Wallace's Line, but a relationship with the West African Picathartes has also been suggested. Using three nuclear markers, we demonstrate that Eupetes is the sister taxon of the South African genus Chaetops , and their sister taxon in turn being Picathartes , with a divergence in the Eocene. Thus, this clade is distributed in remote corners of Africa and Asia, which makes the biogeographic history of these birds very intriguing. The most parsimonious explanation would be that they represent a relictual basal group in the Passerida clade established after a long-distance dispersal from the Australo-Papuan region to Africa. Many earlier taxonomic arrangements may have been based on assumptions about relationships with similar-looking forms in the same, or adjacent, biogeographic regions, and revisions with molecular data may uncover such cases of neglect of ancient relictual patterns reflecting past connections between the continents.


2013 ◽  
Vol 58 (4) ◽  
Author(s):  
Kurt Galbreath ◽  
Kristina Ragaliauskaite ◽  
Leonas Kontrimavichus ◽  
Arseny Makarikov ◽  
Eric Hoberg

AbstractHymenolepidid cestodes in Myodes glareolus from Lithuania and additional specimens originally attributed to Arostrilepis horrida from the Republic of Belarus are now referred to A. tenuicirrosa. Our study includes the first records of A. tenuicirrosa from the European (western) region of the Palearctic, and contributes to the recognition of A. horrida (sensu lato) as a complex of cryptic species distributed broadly across the Holarctic. Specimens of A. tenuicirrosa from Lithuania were compared to cestodes representing apparently disjunct populations in the eastern Palearctic based on structural characters of adult parasites and molecular sequence data from nuclear (ITS2) and mitochondrial (cytochrome b) genes. Morphological and molecular data revealed low levels of divergence between eastern and western populations. Phylogeographic relationships among populations and host biogeographic history suggests that limited intraspecific diversity within A. tenuicirrosa may reflect a Late Pleistocene transcontinental range expansion from an East Asian point of origin.


MycoKeys ◽  
2019 ◽  
Vol 46 ◽  
pp. 1-54 ◽  
Author(s):  
Cathy Cripps ◽  
Ursula Eberhardt ◽  
Nicole Schuetz ◽  
Henry Beker ◽  
Vera Evenson ◽  
...  

Numerous taxa ofHebelomahave been reported in association withSalix,Dryas, andBetulain arctic-alpine habitats. However, species are notoriously difficult to delineate because morphological features overlap, and previously there was little reliable molecular data available. Recent progress in ITS-sequencing within the genus, coupled with an extensive database of parametrically described collections, now allows comparisons between species and their distributions. Here we report 16 species ofHebelomafrom the Rocky Mountain alpine zone from some of the lowest latitudes (latitude 36°–45°N) and highest elevations (3000–4000 m) for arctic-alpine fungi in the northern hemisphere. Twelve of these species have been reported from arctic-alpine habitats in Europe and Greenland and are now molecularly confirmed from the Middle and Southern Rockies, greatly expanding their distribution. These are:Hebelomaalpinum,H.aurantioumbrinum,H.dunense,H.hiemale,H.marginatulum,H.mesophaeum,H.nigellum,H.oreophilum,H.subconcolor,H.spetsbergense,H.vaccinum, andH.velutipes. Hebelomahygrophilumis known from subalpine habitats in Europe, but was never recorded in arctic-alpine ecology. Three species recorded from the Rockies, but as yet not reported from Europe, areH.alpinicola,H.avellaneum, andH.excedens. The last two have never previously been reported from an arctic-alpine habitat. For all three of these species, the holotypes have been studied morphologically and molecularly, and have been incorporated into the analysis.


1987 ◽  
Vol 47 (3) ◽  
pp. 627-647 ◽  
Author(s):  
David F. Weiman

The Upcountry of the Lower South was located on the periphery of the antebellum cotton economy, but some of its subregions were integrated into the market system in the 1850s. An analysis of sample counties in the Georgia Upcountry demonstrates that the spread of market production into the western half of the region depended on local development which created opportunities for diversified market production and increased household wealth through capital gains on improvements. The absence of market development in the eastern half of the region, in contrast, limited the wealth of farm households, reinforcing their economic isolation.


1961 ◽  
Vol S7-III (5) ◽  
pp. 492-500
Author(s):  
Andre R. Meunier

Abstract A region of 40,000 km <sup>2</sup> in the States of Pernambuco, Paraiba, and Rio Grande do Norte in northeastern Brasil, drained to the north by the Piranhas river and to the east by the Paraiba river, exhibits a series of Cenozoic erosion levels showing the morphologic characteristics of littoral and interior zones. Rocks of the region are a poorly-known Precambrian complex attributed to the Algonkian. In the semi-arid western half of the region, west of the meridian of Campina Grande, are the Chapadas, Soledad, and Patos levels, respectively at 830-650, 600-550, and 300-250 m elevation. In the eastern half of the littoral region are the Borborema and Umbuzeiro surfaces, the probably Pliocene Tabuleiros gently sloping from 200 to 20 m at the seacoast, and the Itabaiana surface at about 90 m. These features reflect successive border flexures of the Brazilian shield, and progressive accentuation of an enormous fold at depth.


1986 ◽  
Vol 26 (1) ◽  
pp. 27-48 ◽  
Author(s):  
Stephen C. Porter

Time series depicting mountain glacier fluctuations in the Alps display generally similar patterns over the last two centuries, as do chronologies of glacier variations for the same interval from elsewhere in the Northern Hemisphere. Episodes of glacier advance consistently are associated with intervals of high average volcanic aerosol production, as inferred from acidity variations in a Greenland ice core. Advances occur whenever acidity levels rise sharply from background values to reach concentrations ≥1.2 μequiv H+/kg above background. A phase lag of about 10–15 yr, equivalent to reported response lags of Alpine glacier termini, separates the beginning of acidity increases from the beginning of subsequent ice advances. A similar relationship, but based on limited and less-reliable historical data and on lichenometric ages, is found for the preceding 2 centuries. Calibrated radiocarbon dates related to advances of non-calving and non-surging glaciers during the earlier part of the Little Ice Age display a comparable consistent pattern. An interval of reduced acidity values between about 1090 and 1230 A.D. correlates with a time of inferred glacier contraction during the Medieval Optimum. The observed close relation between Noothern Hemisphere glacier fluctuations and variations in Greenland ice-core acidity suggests that sulfur-rich aerosols generated by volcanic eruptions are a primary forcing mechanism of glacier fluctuations, and therefore of climate, on a decadal scale. The amount of surface cooling attributable to individual large eruptions or to episodes of eruptions is simlar to the probable average temperature reduction during culminations of Little Ice Age alacier advances (ca. 0.5°–1.2°C), as inferred from depression of equilibrium-line altitudes.


2004 ◽  
Vol 41 (3) ◽  
pp. 255-269 ◽  
Author(s):  
Henry C Halls ◽  
Donald W Davis

U–Pb dates on baddeleyite yield ages of 2167.8 ± 2.2 and 2171.6 ± 1.2 Ma on two northeast-trending dykes west of the Kapuskasing Zone in Ontario, Canada. These ages identify the dykes as belonging to the Biscotasing dyke swarm east of the Kapuskasing Zone, which was previously dated at 2166.7 ± 1.4 Ma by U–Pb on baddeleyite and zircon. The new dates show that the Biscotasing swarm was emplaced over an area of at least 300 000 km2, much larger than hitherto suspected, and in a geologically short period of time of about 5 million years. A comparison of paleomagnetic data from Biscotasing and 2.45 Ga Matachewan dykes on either side of the Kapuskasing Zone suggests that the western half of the Superior Province has rotated about 10°–20° counterclockwise relative to the eastern half across the Kapuskasing Zone. This movement may have been accompanied by rifting farther north which ultimately led to the Paleoproterozoic embayment, underlying Hudson Bay, that gives the Superior Province its characteristic butterfly-shaped outline.


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