Faunal Zones Research Articles

Paleobiogeographic significance of Tethyan Lower Cretaceous Cecrops septemporatus Zone radiolarian faunas

The Cecrops septemporatus Zone is widely applied in correlation of Valanginian to lower Hauterivian successions, but paleobiogeographic distributions of radiolarian fauna from this zone remain ambiguous. To address this issue this study compares radiolarian faunas from the Vispi Quarry section, Umbria–Marche Basin, central Italy with the Guigong section, southern Tibet. Similarity between these C. septemporatus Zone faunas suggests a close marine connection may have existed between western and eastern Tethys during Early Cretaceous time. Lithologies, depositional setting, associated fossil records, and paleomagnetic data from contemporaneous radiolarian occurrences in different areas globally are also assessed. The paleobiogeographic distribution of the C. septemporatus Zone fauna was mainly restricted to low latitudes in the Tethyan and Pacific regions, but also shows a significant migration from low latitudes in the Tethyan Realm to mid latitudes in the Boreal and Austral realms. Climatic and oceanographic conditions during the Weissert Event may have played important roles in the development of the paleobiogeographic distribution patterns observed for the C. septemporatus Zone faunas.

Wildlife species commonly involved in the WVC and roadkill along the roadway in plantation area

This paper aimed to discuss wildlife-vehicle collisions along the roadway in Wilayah Jengka, Pahang, Malaysia and provide the data sources for conservation, preservation and mitigation of wildlife. The primary objective of this survey is to reveal and prepare the roadkill inventory of fauna and avifauna mortality in Wilayah Jengka plantation zone due to wildlife-vehicle collisions. Some of the animals are listed under Schedule 1 and others in Schedule 2 of the Act 716. Wildlife-vehicle collisions (WVC) contributes to road mortality of wildlife species in Wilayah Jengka and little is known about roadkill in this area. The highest mortalities include Common Palm Civet (27.41%), Leopard Cat (14.51%), Large Indian Civet & Barn Owl (9.61% each), Clouded Monitor (8.06%), Long-Tailed Macaque & Wild Boar (6.45% each), Monitor Lizard (4.83%), Greater Coucal, Oriental Honey Buzzard & Red Junglefowl (3.22% each), and White-Breasted Waterhen (1.61%).

相机陷阱法在潮间带底栖蟹类群落生态学中的应用研究

PDF HTML阅读 XML下载 导出引用 引用提醒 相机陷阱法在潮间带底栖蟹类群落生态学中的应用研究 DOI: 10.5846/stxb202102080404 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 科技基础资源调查专项（2017FY100701）；厦门大学研究生田野调查基金项目（2020FG022）；国家自然科学基金项目（42076161） Feasibility study on the application of camera trapping method in the study of benthic crab community ecology in the intertidal zone Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:潮间带大型底栖动物调查是滨海湿地生物多样性监测的重要环节。目前普遍应用的传统侵入性调查方法（挖掘法、手捕法和陷阱诱捕法）存在干扰强、耗时久和劳动密集等问题，无法客观反映活动性较强的蟹类等重要功能类群的群落结构和物种多样性。对陆地野生动物研究中常用的相机陷阱法进行了符合潮间带应用条件的便携式设计，并以红树林蟹类为例，通过与3种传统侵入性调查方法进行对比，探讨相机陷阱法在潮间带底栖蟹类群落生态学研究中的应用。结果表明：（1）相机陷阱法在种群密度测定方面比挖掘法提高2.1倍，比手捕法提高10.3倍，比陷阱诱捕法提高16.3倍；（2）相机陷阱法在调查物种数方面均高于3种传统侵入性调查方法，适用于沙蟹科（Ocypodidae）和方蟹科（Grapsidae）蟹类调查；（3）相机陷阱法对个体大小选择性弱，采样更加全面；（4）相机陷阱法在群落alpha多样性（Shannon-Wiener指数）、beta多样性（样方-多度矩阵总方差Var （Y））和功能多样性（Rao二次熵和功能离散度）调查方面整体不弱于侵入性调查方法。此外，相较于侵入性调查方法，相机陷阱法对沉积物结构破坏小、不干扰蟹类群落结构，在兼顾数据丰富性的同时又具有高效性。然而，由于相机陷阱法基于蟹类底表活动性，无法适用于冬季调查、夜行性蟹类和游泳型蟹类调查。未来，相机陷阱法的发展将与基于深度学习的图像处理技术结合以满足数据处理需求。研究揭示了相机陷阱法在潮间带底栖蟹类群落中的应用优越性与局限性，为潮间带大型底栖动物群落生态学的研究提供技术支撑。 Abstract:The investigation of macro-benthic fauna in the intertidal zone is a crucial part of biodiversity monitoring in coastal wetlands. However, there are still some critical gaps, such as the great effects of human disturbance, time-consuming and labor-intensive, that exist in the widely used traditional invasive survey methods (e.g., excavation, hand catch, and pitfall trapping) at present. Thus, it is hard for us to objectively investigate the community structure and biodiversity of important functional groups with intense activity such as crabs. The camera trap is commonly used in the study of terrestrial wildlife. A camera trapping method was designed with the character of portable to meet the application conditions of the intertidal zone. We took crabs in mangrove wetlands as the survey object. Then, the application of the camera trapping method in the study of intertidal benthic crab community ecology was discussed by comparing it with the three traditional invasive survey methods. The results showed that:(1) The camera trapping method was 2.1 times higher than the excavation method, 10.3 times higher than the hand catch method, and 16.3 times higher than the pitfall trapping method in population density determination. (2) The results of the number of species of camera trapping method was higher than the three traditional invasive survey methods. And camera trapping method was suitable for the investigation of Grapsidae and Ocypodidae. (3) The camera trapping method had weak selectivity on individual size and was more comprehensive in sampling. (4) The camera trapping method is no less than invasive survey methods on community alpha diversity (Shannon-Wiener index), beta diversity (total variance of the quadrat-abundance matrix, Var(Y)), and functional diversity (Rao quadratic entropy and functional dispersion). In addition, compared with the invasive survey methods, the camera trapping method has minor damage to the structure of sediment, does not interfere with the crab community structure, and has high efficiency while taking the data richness into account. However, because the camera trapping method is based on the surface activity of crabs, it cannot be applied to winter surveys and surveys of nocturnal crabs and swimming crabs. In the future, the development of camera trapping will be combined with image processing technology based on deep learning to meet data processing needs. This study revealed the advantages and limitations of the camera trapping method in the investigation of the intertidal benthic crab community. It also provided technical support for the study of intertidal macro-benthic community ecology. 参考文献 相似文献 引证文献

High inter-species variability in elemental composition of the twilight zone fauna varies implications for predators and exploitation by humans

While the importance of oceanic micronektonic species in biogeochemical cycles and in the transfer of matter in food webs is globally recognized, specific knowledge on elemental concentrations and their variability within this community is still poorly documented. Here, we report for the first time in the Bay of Biscay, North-East Atlantic, the body composition in various biological parameters and chemical elements of a meso-to bathypelagic micronektonic community. Stable carbon and nitrogen isotope compositions (δ13C, δ15N), C:N ratios, energy density, as well as the concentrations in 6 macro-minerals and 13 trace elements including essential (micro-nutrients) and non-essential elements (undesirables, with no know biological function) were measured in whole organisms of 4 crustacean and 11 fish species caught simultaneously around 800 m depth. The results showed a low variability of δ13C values, confirming that all studied species share the same habitat. On the contrary, large differences were observed among species for several elements. Trace elements showed the greatest variability (i.e. larger range of values), especially silver (Ag), arsenic (As), cadmium (Cd), cobalt and vanadium. Significant differences were also revealed among taxa for Ag, As, Cd, copper and strontium concentrations (with crustaceans > fish), as well as for δ15N values and phosphorus concentrations (with fish > crustaceans). Although concentrations varied greatly among species, they could be grouped according to their energy density and composition in 19 chemical elements, through hierarchical clustering analysis. Six functional groups of species have been thus identified, reflecting contrasted nutritional benefit and/or exposure to undesirables for predators feeding on this deep pelagic community. Finally, the concentrations measured for the potentially toxic trace elements (undesirables) exceeded the existing European thresholds for Cd and to a lesser extent mercury (Hg), which point out potential risks in the perspective of a future exploitation of these deep living resources by humans.

Patterns of spatial and temporal distribution of the macrobenthic fauna on an estuarine macrotidal sandy beach on the Amazon coast (Brazil)

AbstractSeveral attempts have been made to find universal zonation schemes for the benthic fauna in sandy beaches. Usually, the nature and number of zones are not fixed and depend on the beach type and temporal changes in environmental characteristics. We characterized spatial and temporal variations in the structure of macrobenthic communities on an Amazonian macrotidal sandy beach (Farol Beach, Algodoal‐Maiandeua Island, Brazil). Samples (macrobenthos and sediments) were collected during the rainy (March 2012 and 2013) and dry seasons (September 2011 and 2012) at six equidistant sites (50 m apart) from the high tide water mark to the swash zone. The physical gradients influenced the faunal distribution, with significant seasonal variations. Density and diversity increased seaward, while increasing moisture, organic matter content, and fine grains in sediments. Two faunal zonation schemes were observed. In the dry season, three faunal zones were distinguished: upper‐intertidal, mid‐intertidal, and low‐intertidal, whereas in the rainy season, only two faunal zones were distinguished: upper‐intertidal and low‐intertidal. In the rainy season, the physical gradients along the intertidal appeared to be smooth, allowing the expansion of the upper‐tidal zone. This study provides novel insights into macrobenthic distribution patterns, reinforcing that tropical macrotidal beaches have unique characteristics that strongly influence macrobenthic distribution patterns.

Anatomical, morphometric, and stratigraphic analyses of theropod biodiversity in the Upper Cretaceous (Campanian) Dinosaur Park Formation1

The Dinosaur Park Formation (DPF) of Alberta, Canada, has produced one of the most diverse dinosaur faunas, with the record favouring large-bodied taxa, in terms of number and completeness of skeletons. Although small theropods are well documented in the assemblage, taxonomic assessments are frequently based on isolated, fragmentary skeletal elements. Here we reassess DPF theropod biodiversity using morphological comparisons, high-resolution biostratigraphy, and morphometric analyses, with a focus on specimens/taxa originally described from isolated material. In addition to clarifying taxic diversity, we test whether DPF theropods preserve faunal zonation/turnover patterns similar to those previously documented for megaherbivores. Frontal bones referred to a therizinosaur (cf. Erlikosaurus), representing among the only skeletal record of the group from the Campanian–Maastrichtian (83–66 Ma) fossil record of North America, plot most closely to troodontids in morphospace, distinct from non-DPF therizinosaurs, a placement supported by a suite of troodontid anatomical frontal characters. Postcranial material referred to cf. Erlikosaurus in North America is also reviewed and found most similar in morphology to caenagnathids, rather than therizinosaurs. Among troodontids, we document considerable morphospace and biostratigraphic overlap between Stenonychosaurus and the recently described Latenivenatrix, as well as a variable distribution of putatively autapomorphic characters, calling the validity of the latter taxon into question. Biostratigraphically, there are no broad-scale patterns of faunal zonation similar to those previously documented in ornithischians from the DPF, with many theropods ranging throughout much of the formation and overlapping extensively, possibly reflecting a lack of sensitivity to environmental changes, or other cryptic ecological or evolutionary factors.

Macrozooplankton and micronekton community structure and diel vertical migration in the Heard Island Region, Central Kerguelen Plateau

The Kerguelen Plateau is the largest topographic barrier to the eastward flowing Antarctic Circumpolar Current (ACC) in the Indian Sector of the Southern Ocean. The plateau is separated into a northern and southern plateau by the Fawn Trough. The northern plateau has a shallow bathymetry (<700 m) with two prominent island systems, the Kerguelen Islands on the northern end and Heard and McDonald Islands on the southern end. The interaction of the northern and southern branches of the Polar Front with the northern plateau results in a complex oceanographic environment, with potential for dynamic mixing of sub-Antarctic and Antarctic fauna. Furthermore, the High Nutrient Low Chlorophyll (HNLC) water that flows over the northern plateau is subject to natural iron fertilization from the shallow bathymetry (< 700 m), leading to extensive phytoplankton blooms each summer, particularly to the southeast of the Kerguelen Islands. The Heard Island region on the central plateau has been relatively underexplored. In January 2004, the Heard Island Predator-Prey Investigation and Ecosystem Study (HIPPIES) conducted macrozooplankton (RMT-8 trawl) and micronekton (IYGPT trawl) sampling in foraging areas used by top predators in the vicinity of the island. Macrozooplankton and micronekton were sampled day and night from three depth strata (0–100 m, 100–300 m and 300–600 m). In the area south and east of Heard Island, over bathymetry ≥1000 m depth, the water column had characteristics of the southern branch of the Polar Front (S-PF) and the macrozooplankton and micronekton were dominated by Antarctic Zone fauna (e.g., the euphausiids Euphausia triacantha and Euphausia frigida, and the myctophids Krefftichthys anderssoni, Electrona antarctica, Gymnoscopelus braueri and Gymnoscopelus nicholsi). Shallow slope and shelf stations were located north of the S-PF and the macrozooplankton assemblages were influenced by Polar Frontal Zone species (e.g., Euphausia vallentini), while the shelf micronekton were dominated by the bentho-pelagic channichthyids Champsocephalus gunnari and Channichthys rhinoceratus, together with G. nicholsi. Most macrozooplankton migrated from the deep epipelagic (100–300 m) into the surface epipelagic (<100 m) at night, although some macrozooplankton occurred at high densities in the surface epipelagic during the day (e.g., Rhincalanus gigas, Themisto gaudichaudii). Most micronekton species occurred in the mesopelagic layers (300–600 m) during the day, and migrated into the deep and surface epipelagic at night. Only the small but very abundant K. anderssoni utilized the top 300 m during the day. The vertical distributions of macrozooplankton and micronekton are discussed with respect to the foraging behavior and diets of top predators.

Tapeworms in Rodents from the Lower Anabar River Basin, with a Review of Species Diversity of Cestodes in Yakutia, Russia.

We aimed to explore the first data on the fauna of cestodes in rodents from the Lower Anabar River Basin situated in extreme north-western Yakutia, Russia and to develop a biological and biogeographical framework for examination of the species diversity of cestodes from Yakutia, which is an important faunal transition zone in the eastern Palaearctic. Field inventory of cestodes from rodents was conducted for the first time in the region of north-western Yakutia. Species diversity, intensity and prevalence of infection were assessed. It was noted a rather high (up to 82.5%) total cestode prevalence in rodents in the extreme north-western area of Yakutia. In Arvicolinae hosts, we collected specimens of six cestode species of four genera and three families. Arostrilepis microtis and Douthittia nordenskioeldi were first collected in voles Lasiopodomys gregalis from Yakutia (new host and geographical records). The zoonotic parasite Echinococcus multilocularis was found in the liver of L. gregalis. The list of cestodes from rodents in Yakutia based on review of previous publications and the material obtained in the present study includes 24 species of 16 genera and five families. Out of these, 17 parasitise rodents as adults stage and seven as larvae. The fauna of rodent tapeworms from the south subarctic tundra and pre-tundra larch woodlands of the north-western Yakutia is characterised by relatively impoverished species diversity compared to the fauna of cestodes from the taiga zone of the central Yakutia. The decrease in the species diversity of tapeworms does not affect the total infection prevalence of the definitive hosts, which is relatively high in this region.

Cephalopods from the Cretaceous-Paleogene (K-Pg) Boundary Interval on the Brazos River, Texas, and Extinction of the Ammonites

We report on new collections of cephalopods (ammonites and nautilids) from the Cretaceous-Paleogene (K-Pg) successions of the Corsicana and Kincaid formations exposed along the Brazos River in Falls County, Texas. An abundant fauna of eight species comprising four genera of ammonites is described from the Corsicana Formation, including Discoscaphites mullinaxorum n. sp. The presence of abundant aptychi (probably lower jaws) of Discoscaphites and Eubaculites, as well as juvenile specimens, indicates a living population that experienced little postmortem drift. The lytoceratid genus Gaudryceras is also reported for the first time from the Brazos River area. Presence of the index taxon Discoscaphites iris (Conrad, 1858) indicates that the fauna belongs to the D. iris Range Zone, the highest ammonite range zone in North America. Correlation with new and existing microfossil data indicates that the fauna represents the uppermost Maastrichtian, and comparison with published records further suggests that this is the most diverse D. iris Zone fauna yet reported from the Gulf and Atlantic Coastal Plains of North America. Three ammonite genera are recorded from the basal units of the K-Pg event deposit at Brazos, which likely represents deposition in the immediate aftermath of the Chicxulub impact event. A single specimen of the nautilid Eutrephoceras is reported from the Danian Kincaid Formation, less than 300 kyr after the K-Pg boundary. These data provide new information on the differing fate of these cephalopod groups during the K-Pg mass extinction and add to the picture of diverse and abundant Maastrichtian ammonite faunas prior to the Chicxulub impact event.

Upper Oligocene–lower-Middle Miocene peramelemorphians from the Etadunna, Namba and Wipajiri formations of South Australia

The oldest fossils referable to the marsupial order Peramelemorphia (which includes modern bandicoots and bilbies) stratigraphically date from the upper Oligocene of Australia. Here we describe new ancient peramelemorphian remains from the Etadunna, Namba and Wipajiri formations, which fill gaps in the documented evolutionary history of the clade spanning some 10 million years. The identified taxa include three new species of Bulungu that incorporate the oldest stem peramelemorphian known to date from Faunal Zone A of the Etadunna Formation. We also report a new genus and species of potential thylacomyid, which pushes back the divergence of bilbies by ∼10 million years. Finally, we present a phylogenetic analysis that clarifies the evolutionary relationships of these new taxa with a reassignment of the genus Bulungu to Yaraloidea. Kenny J. Travouillon* [Kenny.Travouillon@museum.wa.gov.au], Western Australian Museum, Collections and Research, 49 Kew Street, Welshpool, Western Australia, 6106, Australia; Robin M. D. Beck [R.M.D.Beck@salford.ac.uk], Ecosystems and Environment Research Centre, School of Science, Engineering and Environment, University of Salford, Manchester, UK; Judd A. Case [jcase@ewu.edu], Department of Biology, Eastern Washington University, Cheney, WA, 99004, USA.

Macrofaunal diversity and community structure of the DeSoto Canyon and adjacent slope

Northern Gulf of Mexico canyons are centers of organic matter accumulation and biodiversity, but studies of their finer-scale (sub-100 km) ecological patterns are scarce. Detailed sampling of macrofauna within the DeSoto Canyon was undertaken along 3 depth transects on the canyon wall, axis, and adjacent slope. Sediment, terrain, and water mass parameters were also compiled for the same stations. Within the canyon, macrofaunal abundance decreased, evenness increased, and richness followed the expected parabolic curve with depth, peaking at 1100 m. Cluster analysis identified 3 canyon depth groups that conformed to established bathymetric boundaries for the non-canyon Gulf of Mexico slope: Group I at &lt;500 m, Group II at 669-1834 m, and Group III at &gt;2000 m. Explanatory environmental models indicate that canyon community structure was strongly correlated with oxygen concentration and fluorescence, with a weaker potential influence from any of salinity, particulate organic carbon, sediment organic carbon, or slope. Comparisons of the habitats indicated that abundances were highest on the canyon wall. Slope community structure differed from that of either of the canyon habitats. Environmental models consisted of single variables including oxygen concentration, sediment organic carbon, slope, and temperature with similar explanatory values. Community differences within the canyon and between the canyon and adjoining slope contradict previous findings of a single faunal zone for the whole study area. Factors that may contribute to inter-habitat heterogeneity include potential hydrocarbon seepage, organically enriched sediment deposits along channels, or remnant influence from the Deepwater Horizon spill, warranting more research into this dynamic ecosystem.

The ammonite Kamerunoceras Reyment, 1954 from the Lower Turonian (Upper Cretaceous) of Goulmima, south-eastern Morocco

The classic Lower Turonian Mammites nodosoides Zone fauna of the Akrabou Formation of Goulmima in south-eastern Morocco has yielded a specimen of Kamerunoceras ganuzae (Wiedmann, 1960), the first record of the genus from the fauna; the species was originally described from the Ganuza section in Navarra Province, north-eastern Spain.

Biostratigraphy of the Cistecephalus Assemblage Zone (Beaufort Group, Karoo Supergroup), South Africa

Abstract The late Permian (Lopingian) Cistecephalus Assemblage Zone (CiAZ) of the Karoo Supergroup in South Africa has recently been radiometrically-dated to range from 256 to 255 My. It encompasses approximately one million years of the late Wuchiapingian epoch, at a time when the ancient intra-continental lowlands of southern Gondwana had fully recovered from the end-Guadalupian mass extinction. The diverse Cistecephalus Assemblage Zone fauna is dominated by the small herbivorous dicynodonts Diictodon, Pristerodon and the molelike Cistecephalus, along with a range of larger dicynodont herbivores including Oudenodon, Aulacephalodon, Rhachiocephalus, Dinanomodon and rare Endothiodon. The attendant large carnivores include the gorgonopsians Aelurognathus, Rubidgea, and Smilesaurus, while smaller carnivores are represented by eutherocephalians (e.g., Ictidosuchoides, Ictidosuchops) and small gorgonopsians (e.g., Aloposaurus, Scylacocephalus). Of the parareptiles, the large-bodied taxon Pareiasaurus is most common, with the diminutive pareiasaurs Anthodon, Nanoparia, and Pumiliopareia making their first appearance. Lithostratigraphically, the biozone for the most part coincides with the arenaceous Oukloof and lower Steenkampsvlakte members in the western sub-basin and the equivalent Oudeberg and lower Daggaboersnek members in the east, where it reaches its maximum thickness of 300 m. The Cistecephalus Assemblage Zone thins westwards to 120 m at Teekloof Pass, and eastwards to approximately 100 m near the town of Fort Beaufort.

Trophic ecology of elasmobranch and teleost fishes in a large subtropical seagrass ecosystem (Florida Big Bend) determined by stable isotope analysis

Carbon and nitrogen stable isotope analyses were used to infer relative trophic structure and examine regional variation in trophic dynamics of fishes in the Florida Big Bend, an approximately 300 km stretch of relatively pristine coastline in the eastern Gulf Of Mexico that contains over 250,000 ha of seagrass. The Florida Big Bend is home to a diverse assemblage of fauna; and the ecosystem is regionally important through its support of robust fishing (recreational and commercial) and eco-tourism industries. Stable isotope analyses suggest assemblages of fishes in the Florida Big Bend are trophically diverse, with considerable isotopic overlap across many taxa. Patterns of trophic structure corroborated the results of similar studies of these and related taxa and in other seagrass ecosystems, and there appear to be multiple channels of primary production. Large elasmobranch fishes were most enriched in δ 15N with values well above the teleost fishes sampled, while smaller and demersal elasmobranchs had δ 15N signatures comparable to several species of predatory teleosts. Results of stable isotope analyses suggested high trophic redundancy and overlap in resource use among both teleost and elasmobranch fishes. Comparisons of regional stable isotope values revealed some spatial variability and indicated the southern Big Bend is isotopically distinct, suggesting a distinct regional faunal zone in this region, potentially due to greatly reduced river influence in the southern portion of the system.

Salt-Marsh Foraminiferal Distributions from Mainland Northern Georgia, USA: An Assessment of Their Viability for Sea-Level Studies

We investigated foraminiferal distributions from two salt-marsh sites at Thunderbolt and Georgetown, in mainland northern Georgia, U.S. Atlantic coast. We analyzed modern epifaunal foraminiferal assemblages across multiple transects consisting of 54 surface samples. Multivariate statistical analysis (Partitioning Around Medoids and Detrended Correspondence Analysis) revealed that dead foraminiferal assemblages are divided into three faunal zones, which are elevation-dependent and site-specific. At Thunderbolt, an intermediate salinity marsh (17‰), high marsh assemblages are dominated by Haplophragmoides spp. with an elevational range of 1.19 to 1.68 m mean tide level (MTL) between Mean Higher High Water (MHHW) to Highest Astronomical Tide (HAT). Low marsh assemblages are dominated by Miliammina fusca and Ammobaculites spp. with an elevational range of – 0.05 to 1.14 m MTL (between MTL and MHHW). At Georgetown, a low salinity marsh (6‰), the assemblages are dominated by Ammoastuta inepta with an elevational range of 0.43 to 1.16 m MTL (between MTL and MHHW). We also enumerated living infaunal foraminiferal populations from six 50-cm sediment cores from the two salt marshes to assess implications for interpretations of sea-level change. Peak concentrations of living foraminiferal populations occur in the upper 1-cm surface sediment in five of the six cores. An exception was observed in high marsh settings of Thunderbolt, where Haplophragmoides spp. and Arenoparrella mexicana were observed living down to 40 cm depth and both the live and dead abundance peaked (32 and 520 specimens per 10 cc respectively) between depths of 15–35 cm in the core. The dominant infaunal species were similar to those observed in modern surface samples, and the total number of infaunal foraminifera was typically less than 15% compared to the total number of dead specimens in the surface samples. Finally, we com­pared the down-core patterns of living and dead foraminiferal abundance that suggest that 90% of the tests were removed within the upper 10 cm of sediment in most cores. This may be due to taphonomic alteration from bioturbation and/or microbial processes. Selective preservation between resistant species such as A. mexicana and fragile species like M. fusca and Ammobaculites spp. can change the subsurface foraminiferal assemblage. This has the potential to cause errors in sea-level reconstructions using foraminiferal assemblage from low marsh sediments. This study highlights the modern vertical distribution of salt-marsh foraminifera in mainland northern Georgia and their potential as modern analogues for fos­sil counterparts in reconstructing sea-level changes. Taphonomic processes may cause the absence of foraminiferal tests or differences between modern and fossil assemblages, which could be problematic when performing RSL reconstructions in low marsh environment. Publisher's note: a correction article relating to this paper has been published and can be found at http://doi.org/10.5334/oq.91

Macrofauna bivalve diversity from the deep northern Gulf of Mexico

AbstractAbundance, α diversity, and faunal zonation of infaunal bivalve mollusks were measured along multiple depth transects in the deep northern Gulf of Mexico (GoM) covering depths of 213 to 3,732 m. Density decreased exponentially from the shallow continental slope (0.2–1.0 km) down to the abyssal plain depths (3.0–3.7 km). Diversity increased down the slope to a maximum at intermediate depths (1.2 to 1.8 km), followed by a decrease down to the Sigsbee Deep. The maximum diversities coincided with an organic carbon input of 10 to 16.3 mg C m−2 d−1, whereas the minimum was encountered at the high (ca. 52–78 mg C m−2 d−1) and low extremes (ca. 3–5 mg C m−2 d−1) of the detrital food input. Seven faunal zones could be identified on the basis of species composition with faunal changes being more abrupt on the upper slope compared to the lower slope and abyssal plain, possibly due to steeper gradients in physical variables.

Echolocation calls of some bats of Gujarat, India

Abstract Bats play an important role by providing ecosystem services including pollination, seed dispersal, forest regeneration and insect pest control and also serve as bio-indicators. In the present study, we present an acoustic guide to the calls of nine species of bats from Gujarat belonging to families Rhinopomatidae (Rhinopoma hardwickii, Rhinopoma microphyllum), Emballonuridae (Taphozous melanopogon, Taphozous longimanus and Taphozous nudiventris), Rhinolophidaea (Rhinolophus lepidus), Hipposideridae (Hipposideros galeritus) and Vespertilionidae (Scotophilus heathii, Pipistrellus ceylonicus). Discriminant function analysis was used to classify the bat calls to the species level using leave-one-out cross validation. Analysis was carried out separately for constant frequency (CF) calls and frequency-modulated (FM) calls. Bats echolocating with CF calls were classified with 100% success, while in the case of FM calls, the calls were classified with 66.7% accuracy. In species-rich communities, care should be taken while using echolocation calls to identify bats producing FM calls. More such call libraries of bats from other parts of India are needed for non-invasive documentation of chiropteran fauna in different biogeographic zones.

Carbon isotope and mammal recovery from extreme greenhouse warming at the Paleocene–Eocene boundary in astronomically-calibrated fluvial strata, Bighorn Basin, Wyoming, USA

Massive addition of isotopically-depleted carbon to the ocean and atmosphere caused a carbon isotope excursion (CIE) and global greenhouse warming during the Paleocene–Eocene Thermal Maximum (PETM) circa 56 million years ago. The body of the CIE is followed by a recovery interval that is key to understanding Earth's capacity for carbon uptake, mechanisms of carbon uptake, and biotic responses following an extreme greenhouse warming event. Expanded terrestrial stratigraphic sections in the Bighorn Basin of Wyoming provide exceptionally high-resolution records of the CIE and can be linked directly to the mammalian fossil record.Here, we provide carbon isotope records of unprecedented resolution measured on in-situ pedogenic carbonate nodules in two parallel 8-km-spaced sections of upper Paleocene and lower Eocene fluvial sediments in the northern Bighorn Basin. We find consistent precession-driven sedimentary cycles in the two sections. Cycle thicknesses show significant lateral, and thus vertical, variation, demonstrating that astronomical age models constructed for fluvial successions require detailed sedimentary facies analysis of parallel sites.Plotting the high-resolution carbon isotope records in time using our astronomical age model for the correlated sections indicates a CIE body duration of 101 ± 9 kyr. The CIE shows an initial recovery step of +2.7 ± 1.0‰. This step occurs across the single, well-developed paleosol marker bed known as Purple-4, which represents a time interval of up to 15 kyr. The rapidity of recovery at the end of the CIE body is remarkable in light of existing hypotheses for carbon removal from the ocean–atmosphere system. Concurrent mammal finds show that the transition from faunal zone Wa-0 to faunal zone Wa-1 occurred in two steps, with a transitional Wa-R fauna preceding the CIE initial recovery step and Wa-1 fauna following the step.

The groundwater fauna of the Classical Karst: hydrogeological indicators and descriptors

The Classical Karst (sensu stricto) represents a complex hydro-geomorphological unit as well as one of the best-known karstic systems in the world. For this reason, it was selected as a model area both for applied research and for the conservation of its highly diverse subterranean fauna. With this paper, we aim to provide an overview of groundwater fauna in the phreatic zone of the Classical Karst aquifer, based on all published material along with new surveys, and search for patterns of species distribution within hydrogeological subunits, with a focus on the potential use of species as tracers of hydrological connections and groundwater flowpaths. The Classical Karst, with an area of approximately 750 km2, and adjacent to alluvial and flysch areas provides habitats for 83 stygobionts (accompanied by 16 stygophiles) and is one of the richest hotspots for groundwater fauna across the globe. The rate of endemism within the area is very high (around 50%). Multivariate statistical analyses revealed the faunal turnover between hydrogeological subunits, as well as the effect of water flow regime. Our approach, using species turnover and the species indicator value, allowed us to recognise groups of indicator species, which can be considered as descriptors of aquifer type and habitat structure, as well as water flow regime and groundwater flowpaths.

Magnetochronology of the Entire Chinle Formation (Norian Age) in a Scientific Drill Core From Petrified Forest National Park (Arizona, USA) and Implications for Regional and Global Correlations in the Late Triassic

AbstractBuilding on an earlier study that confirmed the stability of the 405‐kyr eccentricity climate cycle and the timing of the Newark‐Hartford astrochronostratigraphic polarity time scale back to 215 Ma, we extend the magnetochronology of the Late Triassic Chinle Formation to its basal unconformity in scientific drill core PFNP‐1A from Petrified Forest National Park (Arizona, USA). The 335‐m‐thick Chinle section is imprinted with paleomagnetic polarity zones PF1r to PF10n, which we correlate to chrons E17r to E9n (~209 to 224 Ma) of the Newark‐Hartford astrochronostratigraphic polarity time scale. A sediment accumulation rate of ~34 m/Myr can be extended down to ~270 m, close to the base of the Sonsela Member and the base of magnetozone PF5n, which we correlate to chron E14n that onsets at 216.16 Ma. Magnetozones PF5r to PF10n in the underlying 65‐m‐thick section of the mudstone‐dominated Blue Mesa and Mesa Redondo members plausibly correlate to chrons E13r to E9n, indicating a sediment accumulation rate of only ~10 m/Myr. Published high‐precision U‐Pb detrital zircon dates from the lower Chinle tend to be several million years older than the magnetochronological age model. The source of this discrepancy is unclear but may be due to sporadic introduction of juvenile zircons that get recycled. The new magnetochronological constraint on the base of the Sonsela Member brings the apparent timing of the included Adamanian‐Revueltian land vertebrate faunal zone boundary and the Zone II to Zone III palynofloral transition closer to the temporal range of the ~215 Ma Manicouagan impact structure in Canada.